Glossary

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• AbdomenThe area of the body between the bottom of the ribs and the top of the thighs.
• Abdominal AnginaAn acute attack of severe abdominal pain, commonly occurring after eating and often associated with weight loss, nausea, vomiting and diarrhoea. It is caused by narrowing or obstruction of the mesenteric arteries, primarily atherosclerotic in origin
• Abdominal AortaThe portion of the aorta in the abdomen
• AblationElimination or removal.
• Abnormal Heart RhythmAnother term for an arrhythmia
• ACE InhibitorsACE inhibitors are commonly used to treat heart failure and high blood pressure and often prescribed to patients following a heart attack.
• AcetylcholineA type of chemical (called a neurotransmitter) that transmits messages among nerve cells and muscle cells.
• Acquired Brain Injury Is an injury caused to the brain since birth. There are many possible causes, including a fall, a road accident, tumour, stroke and hypoxia e.g. from a cardiac arrest.
• ABI Is an injury caused to the brain since birth. There are many possible causes, including a fall, a road accident, tumour, stroke and hypoxia e.g. from a cardiac arrest.
• Acquired Heart DiseaseDisease of the heart that develops after birth, due to an infection or other disease affecting the heart muscle, heart valves or coronary arteries (compare with 'Congenital Heart Disease').
• Acute Coronary SyndromeMedical term for acute conditions associated with possible or actual heart damage due to restricted blood supply. Incorporates unstable angina, NSTEMI and STEMI. The latter two terms are also called a heart attack.
• Acute Myocardial InfarctionMedical term for a Heart Attack. The myocardium (heart muscle) is damaged, usually as a result of acute restriction of the coronary blood supply.
• Acute Respiratory Distress SyndromeWhen the lungs do not work sufficiently leading to rapid and shallow breathing.
• ARDSWhen the lungs do not work sufficiently leading to rapid and shallow breathing.
• Adrenaline This hormone is secreted by the adrenal glands in response to stress and other challenges to the body. The release of adrenaline causes a number of changes throughout the body, including the metabolism of carbohydrates to supply the body’s energy demands and increased arousal or alertness
• ALSA structured and algorithm-driven method of life support for use in the severest of medical emergencies, especially cardiac arrest. Doctors, nurses and paramedic personnel involved in ALS receive special training in the use of equipment.
• Advance Life SupportA structured and algorithm-driven method of life support for use in the severest of medical emergencies, especially cardiac arrest. Doctors, nurses and paramedic personnel involved in ALS receive special training in the use of equipment.
• Advance Trauma Life SupportThis is specifically for patients who have been subjected to major trauma, such as a serious road traffic accident
• ATLSThis is specifically for patients who have been subjected to major trauma, such as a serious road traffic accident
• Aerobic ExerciseRepetitive, rhythmic exercise involving your muscles e.g. brisk walking, cycling and swimming.
• Agonal Breathing Agonal breathing is when someone who is not getting enough oxygen is gasping for air. It is usually due to cardiac arrest or stroke. It's not true breathing. It's a natural reflex that happens when your brain is not getting the oxygen it needs to survive.  Agonal breathing is a sign that a person is near death. It's also a sign that the brain is still alive. People who have agonal breathing and are given CPR are more likely to survive cardiac arrest than people without agonal breathing.
• AirwayThe passage(s) through which the patient breathes. Naturally this is a patient’s nose and mouth. When patients are sedated and ventilated this can refer to the endotracheal tube or tracheostomy. Occasionally used as a shorthand reference to an oropharyngeal or nasopharyngeal airway – these are smaller plastic tubes that can be inserted into the patient’s nose or mouth to help keep their natural ‘airway’ open
• AlgorithmA set of precise rules or procedures programmed for example into an implantable device (pacemaker, CRT, ICD or ILR) that are designed to solve a specific problem.
• AlveoliAir sacs in the lungs where oxygen and carbon dioxide are exchanged.
• AmiodaroneA kind of medicine (called an antiarrhythmic) used to treat irregular heart rhythms such as atrial fibrillation and ventricular tachycardia. It works by regulating nerve impulses in your heart. Amiodarone is mainly given to patients who have not responded to other antiarrhythmic medicines.
• AmnesiaFailure of memory
• Amygdala Part of the brain’s limbic system, this primitive brain structure lies deep in the centre of the brain and is involved in emotional reactions, such as anger or fear, as well as emotionally charged memories. It also influences behaviour such as feeding, sexual interest, and the immediate “fight or flight” stress reaction that helps ensure the person’s needs are met.
• Anemia A reduction in the hemoglobin of red blood cells with consequent deficiency of oxygen in the blood, leading to weakness and pallor
• Aneurysm A swelling/dilation sac-like protrusion from a blood vessel or the heart, resulting from a weakening of the vessel wall or heart muscle.
• AnginaChest pain that occurs when diseased blood vessels restrict blood flow to the heart.
• AngiogramX-ray picture of blood vessels and cardiac chambers using contrast.
• AngiographyAn x-ray technique in which dye is injected into the chambers of your heart or the arteries that lead to your heart (the coronary arteries). The test lets doctors measure the blood flow and blood pressure in the heart chambers and see if the coronary arteries are blocked.
• AngioplastyA nonsurgical technique for treating diseased arteries by temporarily inflating a tiny balloon inside an artery.
• ACEA medicine that lowers blood pressure by interfering with the breakdown of a protein-like substance involved in blood pressure regulation
• Angiotensin-converting Enzyme InhibitorA medicine that lowers blood pressure by interfering with the breakdown of a protein-like substance involved in blood pressure regulation
• Angiotensin II Receptor BlockerA medicine that lowers blood pressure by blocking the action of angiotensin II, a chemical in the body that causes the blood vessels to tighten (constrict)
• AnnulusThe ring around a heart valve where the valve leaflet merges with the heart muscle.
• AnomiaThe inability to name objects or items.
• Anosmia
  Loss of sense of smell.
• AnoxiaComplete oxygen starvation. A condition in which the oxygen supply to the tissues is cut off completely. Partial loss of oxygen supply to the tissues is known as HYPOXIA.
• AntiarrhythmicsMedicines used to treat patients who have irregular heart rhythms.
• AntibioticsA medicine, which may be taken by mouth as a syrup, tablet or capsule, or may be given through a drip into a vein, to prevent or treat a bacterial infection.
• AnticoagulantAny medicine that keeps blood from clotting; a blood thinner.
• AntidepressantsAntidepressants aim to treat the symptoms of depression and can help people experiencing depression to feel more motivated and energetic.This group of medication may also be used to treat obsessive-compulsive disorder, anxiety and eating disorders.There are different types of antidepressants including tricyclic and selective serotonin reuptake inhibitors (SSRIs).
• AntihypertensiveAny medicine or other therapy that lowers blood pressure.
• Antiplatelet TherapyMedicines that stop blood cells (called platelets) from sticking together and forming a blood clot
• Antitachycardia PacingRecognized as a way to pace-terminate certain types of arrhythmias, especially slow monomorphic VT involving a reentry circuit. The idea is to deliver a few seconds of pacing stimuli to the heart at a rate faster than tachycardia
• ATPRecognized as a way to pace-terminate certain types of arrhythmias, especially slow monomorphic VT involving a reentry circuit. The idea is to deliver a few seconds of pacing stimuli to the heart at a rate faster than tachycardia
• AnxietyThis is the term used to describe experiences such as chronic fear, tension and panic attacks. Some people have an overwhelming feeling of dread that prevents them getting on with everyday life. Sleepless nights and recurring thoughts are common, as well as nausea, palpitations, dizziness and difficulty in breathing. Anxiety is the most common mental health problem people experience.
• Anxiety disordersThese are disorders that involve a continuous state of anxiety or fear, lasting at least a month, marked by constant apprehension, difficulties in concentration and a pounding heart. Physical symptoms may also be present, such as headaches, sweating, irritability, and nausea. Anxiety disorders include panic disorder and obsessive-compulsive disorder. Depression is common in those with anxiety disorders
• AortaThe largest artery in the body and the main vessel to supply blood from the heart.
• Aortic ArchThe head and neck vessels arise from this part of the aorta, directing blood from the heart; the remainder of the blood then goes down to the rest of the body.
• Aortic Atresia
  Complete obstruction to the aortic valve or the aorta (usually associated with Hypoplastic Left Heart Syndrome)
• Aortic Regurgitation (reflux)Backwards leakage of circulating blood from the aorta into the left ventricle due to failure of the valve to close properly or to perforation. The leak can be trivial, mild, moderate, or severe.
• Aortic StenosisNarrowing of the aortic valve resulting from a congenital defect of the valve leaflets or disease of the valve.
• Aortic ValveThe valve at the origin of the aorta, which controls flow of blood out of the heart and prevents backflow.
• ApathyA direct result of brain injury to frontal lobe structures which concern emotion, motivation and forward planning.
• Aphasia The inability to speak, write or understand spoken or written language because of brain injury or disease. There are different levels of impairment and the term dysphasia refers to a partial loss of language whereas aphasia refers to a complete loss of language. However, in practice, the terms are interchangeable
• ApnoeaTemporary cessation of breathing from any cause, formally defined as a reduction in nasal airflow to less than 30% of normal for more that 10 seconds
• Apoptosis A form of programmed cell death that occurs as part of normal growth and development. However, in cases of brain disorders or disease, this natural process can be "hijacked" resulting in the unnecessary death of crucial neurons.
• Apraxia Inability to plan and perform purposeful movements, while still having the ability to move and be aware of movements.
• ArachnoidThe middle of the three membranes covering and protecting the brain and spinal cord. The arachnoid membrane lies below the DURA mater and directly above the SUBARACHNOID SPACE.
• Arrest (Cardiac)Cessation of the heart’s normal rhythmic electrical and/or mechanical activity which causes immediate haemodynamic compromise. A major cause of death.
• ArrhythmiaAn abnormal heartbeat.
• Arrhythmogenic cardiomyopathy Arrhythmogenic cardiomyopathy (ACM) is a rare condition where the heart’s structure can become weak. This is because the cells of the muscle tissue don’t develop as they should. The walls of your heart can become weak. And your heart might not be able to pump blood as well as it should.  Sometimes you might see ACM (arrhythmogenic cardiomyopathy) being called ARVC (arrhythmogenic right ventricular cardiomyopathy). The condition used to be called ARVC because it was thought to only(...)
• ACM Arrhythmogenic cardiomyopathy (ACM) is a rare condition where the heart’s structure can become weak. This is because the cells of the muscle tissue don’t develop as they should. The walls of your heart can become weak. And your heart might not be able to pump blood as well as it should.  Sometimes you might see ACM (arrhythmogenic cardiomyopathy) being called ARVC (arrhythmogenic right ventricular cardiomyopathy). The condition used to be called ARVC because it was thought to only(...)
• Arrhythmogenic Right Ventricular DysplasiaARVD is a type of cardiomyopathy with no known cause. It appears to be a genetic condition (passed down through a family’s genes). ARVD causes ventricular arrhythmias
• ARVDARVD is a type of cardiomyopathy with no known cause. It appears to be a genetic condition (passed down through a family’s genes). ARVD causes ventricular arrhythmias
• Art therapyArt therapy aims to support people’s recovery using art as a creative process and as a therapy to help people resolve emotional conflicts, be more aware about themselves, develop social skills, reduce anxiety and increase their self-esteem.
• Arterial LineMost ICU patients have an arterial line usually in the wrist. Arterial lines are connected to the monitor and show your blood pressure. It also allows us to take blood samples.
• Arterial lineA very thin tube (catheter) inserted into an artery to allow direct measurement of the blood pressure, the amount of oxygen and carbon dioxide in the blood.
• ArteriographyA test that is combined with cardiac catheterization to visualize an artery or the arterial system after injection of a contrast dye.
• ArteriolesSmall, muscular branches of arteries. When they contract, they raise resistance to blood flow, and blood pressure in the arteries increases.
• ArteriosclerosisA disease process, commonly called “hardening of the arteries”, which includes a variety of conditions that cause artery walls to thicken and lose elasticity.
• ArteritisInflammation of the arteries.
• ArteryA vessel that carries oxygen-rich blood to the body.
• Artificial HeartA manmade heart. Also called a total artificial heart (TAH)
• Artificial ValvesThese are man made substitutes for heart valves, used to replace a defective valve.
• Ascending AortaThe first portion of the aorta, emerging from the heart’s left ventricle
• AspirinAcetylsalicylic acid; a medicine used to relieve pain, reduce inflammation, and prevent blood clots.
• AtaxiaAbnormal movements due to loss of co-ordination of the muscles.
• Aterial ValveOne of the valves which control flow from the ventricles into the circulation, during each heart beat, and prevent backflow. (see 'Aortic Valve' and 'Pulmonary Valve').
• AtherectomyA nonsurgical technique for treating diseased arteries with a rotating device that cuts or shaves away material that is blocking or narrowing an artery.
• AtheromaBuild-up of fatty deposits in the blood vessels which restricts blood flow. Due to a number of risk factors.
• AtherosclerosisA disease process that leads to the buildup of a waxy substance, called plaque, inside blood vessels.
• AthetosisAbnormal writhing movements, particularly of the hands, seen in a number of brain disorders and following brain injury.
• AtorvastatinUsed to lower cholesterol and other lipids, and to reduce the rish of heart and blood vessel disease
• AtresiaComplete obstruction to a valve or blood vessel, so that blood cannot get past this point in the circulation and has to take an alternative route.
• AFThis is a common abnormal heart rhythm that happens when electrical impulses fire off from different places in the atria (the top chambers of the heart) in a disorganised way. This causes the atria to twitch, and results in an irregular heartbeat or pulse. Atrial fibrillation is a major cause of stroke.
• Atrial FibrillationThis is a common abnormal heart rhythm that happens when electrical impulses fire off from different places in the atria (the top chambers of the heart) in a disorganised way. This causes the atria to twitch, and results in an irregular heartbeat or pulse. Atrial fibrillation is a major cause of stroke.
• Atrial FlutterA type of arrhythmia in which the upper chambers of the heart (the atria) beat very fast, causing the walls of the lower chambers (the ventricles) to beat inefficiently as well
• Atrial Myxomathis is a tumour of the heart, usually of the left side, arising from septum dividing the two upper chambers.
• Atrial Natriuretic PeptideThis is produced in the artria of the heart in response to a rise in atrial pressure
• ANPThis is produced in the artria of the heart in response to a rise in atrial pressure
• Atrial Septal DefectA defect (hole) in the atrial septum which allows blood to shunt from one atrium to the other.
• ASDA defect (hole) in the atrial septum which allows blood to shunt from one atrium to the other.
• Atrial SeptumThe septum (partition or wall) between the two atriums.
• Atrial TachycardiaA type of arrhythmia that begins in the heart’s upper chambers (the atria) and causes a very fast heart rate of 160 to 200 beats a minute. A resting heart rate is normally 60 to 100 beats a minute
• AtrioventricularRelating to the junction between the atriums and the ventricles of the heart.
• Atrioventricular BlockAn interruption or disturbance of the electrical signal between the heart’s upper two chambers (the atria) and lower two chambers (the ventricles)
• Atrioventricular BundleA bundle of modified heart muscle fibres (Purkinje fibres) passing from the atroventricular node forward to the septum between the ventricles, where it divides into right and left bundles, one for each ventricle, The fibres transmit contraction waves from the atria, via the AV node to the ventricles
• AVNRTRe-entry tachycardia arising from the presence of an abnormal electrical connection between atria and ventricles situated within the atrioventricular node
• Atrioventricular Nodal Re-Entry TachycardiaRe-entry tachycardia arising from the presence of an abnormal electrical connection between atria and ventricles situated within the atrioventricular node
• Atrioventricular NodeA group of cells in the heart located between the upper two chambers (the atria) and the lower two chambers (the ventricles) that regulates the electrical current that passes through it to the ventricles
• AVRTRe-entry tachycardia arising from the presence of an abnormal electrical connection between atria and ventricles situated outside the atrioventricular node
• Atrioventricular Reciprocating TachycardiaRe-entry tachycardia arising from the presence of an abnormal electrical connection between atria and ventricles situated outside the atrioventricular node
• Atrioventricular Septal DefectA defect (hole) involving both the atrial and ventricular septums. The mitral and tricuspid valves are also abnormal.
• Atrioventricular Synchrony The normal activation sequence of the heart in which the atria contract and then, after a brief delay, the ventricles contract. AV Synchrony optimizes the heart's output of blood and produces the greatest efficiency in the cardiovascular system
• Atrioventricular ValveOne of the valves which control blood flow from the atriums to the ventricles, and prevent backflow. (see 'Mitral Valve' and 'Tricuspid Valve').
• AtriumEither one of the heart’s two upper chambers.
• Auditory Cortex Part of the brain’s temporal lobe, this region is responsible for hearing. Nerve fibres extending from the inner ear carry nerve impulses generated by sounds into the auditory cortex for interpretation
• Austin Flint MurmurA heart murmur that is loudest in diastole and associated with a third heart sound. It is a sign of aortic regurgitation, which allows retrograde filling and rapid rise in left intraventricular pressure
• AutologousRelating to self. For example, autologous stem cells are those taken from the patient’s own body.
• AEDA type of external defibrillator that can analyse the heart rhythm it detects and advise via voice prompts on therapy to be given according to the latest guidelines. In cases of ventricular fibrillation, some defibrillators will make decisions on delivering electric shocks and do so after issuing appropriate warnings to attending health care professionals
• Automated External DefibrillatorA type of external defibrillator that can analyse the heart rhythm it detects and advise via voice prompts on therapy to be given according to the latest guidelines. In cases of ventricular fibrillation, some defibrillators will make decisions on delivering electric shocks and do so after issuing appropriate warnings to attending health care professionals
• Automatic Implantable Cardioverter DefibrillatorA surgically implanted device that checks the hearts electrical signals and delivers electrical therapy when it senses a dangerous heart rhythm.
• Autonomic Nervous System Part of the central nervous system that controls internal organ functions (e.g., blood pressure, respiration, intestinal function, urinary bladder control, perspiration, body temperature). Its actions are mainly involuntary.
• AutopulseA mechanical device designed to compress the chest (and thereby the heart) rhythmically, with the airm of maintaining the circulation during cardiac arrest. It is more efficient that manual chest compressions and has the advantage of allowing percutaneous coronary intervention to be performed without interuption of chest compressons
• AutoregulationWhen blood flow to an organ stays the same although pressure in the artery that delivers blood to that organ may have changed.
• AV Canal DefectAn operation which involves placing a band of narrow tape around the main pulmonary artery to reduce blood flow and pressure in the lungs. This is a temporary operation used to alleviate the effects of some heart problems . The banding delays the need for further heart surgery until a more appropriate time, e.g. allowing time for the baby to grow.
• AVPU A system for assessing the depth of unconsciousness: A - AlertV - Voice responses presentP - Pain responses presentU - Unresponsive It is used for judging the severity of a head injury
• AxonParts of nerve cells in the brain which look like small hair-like tentacles. The cells receive information via the dendrites and communicate with each other by passing electrical signals down the axons and releasing chemical signals at their ends.
• Axon Terminal The very end of the axon, where electrochemical signals are passed through the synapse to neighbouring cells by means of neurotransmitters and other neurochemicals. A collection of axons coming from, or going to, a specific brain area may be called a white matter fibre tract.

• b

• BacteriaGerms that can lead to disease.
• Bacterial EndocarditisA bacterial infection of the lining of the heart’s chambers (called the endocardium) or of the heart’s valves
• Balloon AngioplastyA procedure to open a narrowed (stenosed) blood vessel using a balloon-tipped catheter threaded through the vessel. The balloon is inflated to open the diseased vessel. For cardiology, most commonly is referring to angioplasty of a coronary artery.
• Balloon CatheterA long tube-like device with a small balloon on the end that can be threaded through an artery. Used in angioplasty or valvuloplasty
• Balloon ValvuloplastyA procedure to repair a heart valve. A balloon-tipped catheter is threaded through an artery and into the heart. The balloon is inflated to open and separate any narrowed or stiffened flaps (called leaflets) of a valve
• Basal GangliaCollections of grey matter in the deep areas of the brain, below the cerebral cortex. They are involved in the control of movement and injury may produce a disturbance resembling Parkinson's disease.
• BLSThe provision of treatment designed to maintain adequate circulation and ventilation to a patient in cardiac arrest, without the use of drugs or specialist equipment.
• Basic Life SupportThe provision of treatment designed to maintain adequate circulation and ventilation to a patient in cardiac arrest, without the use of drugs or specialist equipment.
• Basilar Artery Located at the base of the skull, the basilar artery is a large, specialized blood vessel that supplies oxygenated blood to the brain and nervous system.
• Beta-blockerAn antihypertensive medicine that limits the activity of epinephrine, a hormone that increases blood pressure.
• BicuspidA valve that has two cusps.
• Biomarkers A measurable physiological indicator of a biological state or condition. For example, amyloid plaques—as detected on amyloid PET scans—are a biomarker of Alzheimer’s disease. Biomarkers can be used for both diagnostic and therapeutic purposes.
• BiopsyThe process by which a small sample of tissue is taken for examination.
• BisoprololA medication to treat Hypertension, Heart Failure and Angine. It is a Beta-adrenoceptor blocking medicine, referred to as a beta-blocker.
• Blalock-Taussig ProcedureA shunt between the subclavian and pulmonary arteries used to increase the supply of oxygen-rich blood in “blue babies”
• BlindsightA phenomenon in which people who are perceptually blind in a certain area of their visual field demonstrate some response to visual stimuli.
• Blood ClotA jelly-like mass of blood tissue formed by clotting factors in the blood. Clots stop the flow of blood from an injury. Clots can also form inside an artery when the artery’s walls are damaged by atherosclerotic buildup, possibly causing a heart attack or stroke
• Blood GasCommonly used shorthand for ‘blood gas analysis’. Core monitoring tool widely used in intensive care. Small blood samples (1-2mls) are taken regularly from a patient’s arterial line and processed through an analyser on the unit. Measures blood pH and levels (partial pressures) of oxygen and carbon dioxide. Results are used to adjust organ support therapies.
• Blood Gas MachineA machine that measures the blood gases.
• Blood GasesA blood test to check the level of oxygen carbon dioxide and acidity which may be done several times a day.
• PO2The level of oxygen in the blood
• Blood Oxygen LevelThe level of oxygen in the blood
• Blood PressureA measure of the pressure with which the heart pumps blood into the circulation, usually referred to by two numbers. The 'systolic' pressure refers to the maximum pressure in the artery during each heart beat, while the 'diastolic' pressure is the minimum pressure between heart beats. The left side of the heart and the arteries are operating as a high pressure system, while the veins, the right side of the heart and the pulmonary circulation operate at a much lower pressure.
• Blood Pressure CuffA device usually placed around the upper portion of the arm to measure blood pressure.
• Blood TestsMany blood tests may be needed before and after heart surgery, or at other times. They may include blood counts to detect anaemia or infection, or chemical analysis to detect an imbalance in the blood or build up of harmful acid or waste products. During the early days after surgery and while patients are having drug treatment for congestive heart failure, chemical imbalances in the blood are frequent and may require medications to be altered. Some medicines need to be checked to see how(...)
• Blood TransfusionUsually refers to an infusion of donated red blood cells (RBCs)
• Blood VesselsThese are networks of hollow tubes that transport blood around your body.
• Blue BabiesBabies who have a blue tinge to their skin (cyanosis) resulting from insufficient oxygen in the arterial blood. This condition often indicates a heart defect
• Blue BloaterThe characteristic appearance of a patient suffering from heart failure as a result of chronic obstructive pulmonary disease, marked by cyanosis, oedema, and breathlessness at rest. The left ventricle of the heart is enlarged
• Body Mass IndexA number that indicates an increased risk of cardiovascular disease from a person being overweight. BMI is calculated using a formula of weight in kilograms divided by height in meters squared (BMI =W [kg]/H [m2]). Click here for a BMI calculator
• BMIA number that indicates an increased risk of cardiovascular disease from a person being overweight. BMI is calculated using a formula of weight in kilograms divided by height in meters squared (BMI =W [kg]/H [m2]). Click here for a BMI calculator
• BrachytherapyA procedure using radiation treatment to prevent re-blockage following angioplasty or stent placement in a coronary artery.
• BradyPrefix meaning 'slow'.
• BradycardiaAbnormally slow heartbeat.
• Brain-Derived Neurotrophic Factor Sometimes referred to as “brain fertilizer,” BDNF is a protein that helps promote the growth, maintenance, and survival of neurons.
• BDNF Sometimes referred to as “brain fertilizer,” BDNF is a protein that helps promote the growth, maintenance, and survival of neurons.
• Brain Imaging Refers to various techniques, such as magnetic resonance imaging (MRI), diffusion tensor imaging (DTI), and positron emission tomography (PET), that enable scientists to capture images of brain tissue and structure and to reveal what parts of the brain are associated with behaviours or activities. Structural brain imaging is concerned with identifying the anatomy of the brain and its changes with disease. Functional brain imaging is concerned with identifying the pattern of activity in(...)
• Brain Natriuretic PeptideBlood enzyme which can be measured to diagnose Heart Failure (HF)
• Brain plasticityThe ability of intact brain nerve cells (neurones) to make new connections and, in some cases, take over functions of damaged cells. Neuronal plasticity plays a crucial role in memory and diminishes as a person gets older.
• BrainstemThe lower extension of the brain where it connects to the spinal cord. Neurological functions located in the brain stem include those necessary for survival (breathing, heart rate) and for arousal (being awake and alert).
• Breathing MachineThe breathing machine blows air and oxygen in and out of the lungs. The breathing machine can do all the breathing for the patient or it can assist the patient's own breathing
• Bridge to TransplantUse of mechanical circulatory support to keep heart failure patients alive until a donor heart becomes available
• Broca's areaAn area of the brain crucial to language processing, speech production and understanding
• BronchoscopeThis procedure is carried out using a fibre-optic camera device. The bronchoscope is passed through the patient’s breathing tube into the air passages leading to the lungs allowing the doctor to see into the airways of the lungs
• Brugada SyndromeA genetic disorder that can cause a dangerous irregular heartbeat. When this happens, the lower chambers of your heart (ventricles) beat fast and irregularly. This prevents blood from circulating correctly in your body. This can be dangerous and may lead to fainting or even death, especially during sleep or rest. The disease has been called sudden, unexplained nocturnal death syndrome because people with it can often die in their sleep.
• BruitA sound made in the blood vessels resulting from turbulence, perhaps because of a buildup of plaque or damage to the vessels.
• Bundle Branch BlockA condition in which parts of the heart’s conduction system are defective and unable to conduct the electrical signal normally, causing an irregular heart rhythm (arrhythmia)
• BypassSurgery that can improve blood flow to the heart (or other organs and tissues) by providing a new route, or “bypass” around a section of clogged or diseased artery.
• Bypass Operation
  An operation needing 'Heart Lung Bypass'. This refers to the use of the heart lung bypass machine, which takes over the function of the heart and the lungs, pumping blood round the body and supplying oxygen to the blood. (When people refer to a 'double bypass' or 'triple bypass' operation, etc., they are usually referring to an operation to provide a bypass for blocked coronary arteries, usually in adults with Coronary Heart Disease. This is not the same as a Bypass Operation, although(...)

• c

• Calcium Channel BlockerA medicine that lowers blood pressure by regulating calcium-related electrical activity in the heart
• Calcium Channel Blocker (or calcium blocker)A class of drug used to treat angina, hypertension and sometimes arrhythmias.
• CannulaA very small tube introduced into a vein to provide access for a 'drip'
• CapillaryA microscopic blood vessel connecting arteries to veins. The blood constituents seep through these tiny vessels in the systemic (body) circulation and pulmonary (lung) circulation. Their walls are extremely thin and allow oxygen, carbon dioxide, glucose and other chemicals to pass to and fro between the blood and the surrounding cells in the body organs, or air sacs in the lungs.
• Carbon DioxideIs the waste gas eliminated by the lungs.
• CardiacPertaining to the heart.
• Cardiac AmyloidosisA disorder caused by deposits of an abnormal protein (amyloid) in the heart tissue, which make it hard for the heart to work properly. Also called “stiff heart syndrome”
• Cardiac ArrestThe medical term for a heart stoppage. The most common cause is a heart attack but there are other causes. In cardiac arrest there is an electrical malfunction in the heart, resulting in an irregular heartbeat that disrupts the effective pumping action of the heart. As a result, the heart cannot pump blood to the brain and other organs. Death can occur within minutes if cardiopulmonary resuscitation (CPR) and defibrillation are not carried out.
• Cardiac CachexiaA term for the muscle and weight loss caused by severe heart disease. It is often related to the depressed cardiac output associated with end-stage heart failure, but it can also occur with severe coronary artery disease
• Cardiac CatheterizationA procedure that involves inserting a fine, hollow tube (catheter) into an artery, usually in the groin area, and passing the tube into the heart. Often used along with angiography and other procedures, cardiac catheterization has become a primary tool for visualizing the heart and blood vessels and diagnosing and treating heart disease
• Cardiac DopplerA test using sound waves to produce images of the heart as it is beating.
• Cardiac Enzyme TestsBlood tests which measure the level of certain enzymes (usually Troponin but also CK) in your blood which are released by heart muscle (myocardium) during a heart attack.
• Cardiac EnzymesComplex substances capable of speeding up certain biochemical processes in the heart muscle. Abnormal levels of these enzymes signal heart attack
• Cardiac Heart FailureSometimes also known as Congestive Heart Failure, occurs when your heart muscle doesn't pump blood as well as it should
• Cardiac Navigation SystemThree-dimensional mapping of electromechanical function of the heart to assess blood flow.
• Cardiac OutputThe amount of blood the heart pumps through the circulatory system in one minute
• Cardiac RehabilitationA programme of staged exercises and lifestyle classes designed for people recovering from an arrest and heart attack, these are run through the local hospital by dedicated health care professionals, these may include nurses, physiotherapists.
• CRT-D
  An implantable cardioverter defibrillator (ICD) with cardiac resynchronization pacing therapies. The device terminates an erratic, life-threatening cardiac arrhythmia by delivering a high-energy, direct current electrical stimulus to cardiac tissue. In addition, it provides resynchronization pacing therapies to both ventricles of the heart.
• Cardiac Resynchronization Therapy-DefibrillatorAn implantable cardioverter defibrillator (ICD) with cardiac resynchronization pacing therapies. The device terminates an erratic, life-threatening cardiac arrhythmia by delivering a high-energy, direct current electrical stimulus to cardiac tissue. In addition, it provides resynchronization pacing therapies to both ventricles of the heart.
• CRT-PA device that sends small electrical impulses to both lower chambers of the heart to resynchronize the ventricles.
• Cardiac Resynchronization Therapy-Pacemaker A device that sends small electrical impulses to both lower chambers of the heart to resynchronize the ventricles.
• Cardiac TamponadeThis is a dangerous situation in which there is a build-up of fluid around the heart within the pericaridal sac. This causes compression of the heart, which is therefore unable to fill with blood adequately in order to pump effectively
• CardiologistA doctor who specializes in the study of the heart and its function in health and disease.
• CardiologyThe study of the heart and its function in health and disease.
• CardiomegalyAn enlarged heart. It is usually a sign of an underlying problem, such as high blood pressure, heart valve problems, or cardiomyopathy.
• CardiomyopathyA disease of the heart muscle that leads to generalized deterioration of the muscle and its pumping ability.
• CardiomyopexyStitching of pectoral muscle to cardiac muscle inorder to augment vascular supply to the heart muscle
• CardiomyoplastyReinforcement of cardiac muscle contractility by transfer of lattismus dorsi to surround the heart and to contract synchronously with cardiac muscle
• CardioplegiaTechnique in which the heart is stopped by injecting it with a solution of salts, by hypothermia, or by an electrical stimulus, this helps with complex cardiac surgery and transplants to be performed safely
• Cardiopulmonary BypassThe process by which a machine is used to do the work of the heart and lungs so the heart can be stopped during surgery
• Cardiopulmonary Resuscitation
  An emergency measure that can maintain a person’s breathing and heartbeat. The person who performs CPR actually helps the patient’s circulatory system by breathing into the patient’s mouth to give them oxygen and by giving chest compressions to circulate the patient’s blood. Hands-only CPR involves only chest compressions
• CPRAn emergency measure that can maintain a person’s breathing and heartbeat. The person who performs CPR actually helps the patient’s circulatory system by breathing into the patient’s mouth to give them oxygen and by giving chest compressions to circulate the patient’s blood. Hands-only CPR involves only chest compressions
• CPRIC It has been hypothesized that owing to a variety of physiologic variables, such as autoregulation, comorbidities, and cerebral ischemic thresholds, it is possible for patients receiving high-quality cardiopulmonary resuscitation (CPR) to maintain consciousness
• Cardiopulmonary resuscitation–induced consciousness It has been hypothesized that owing to a variety of physiologic variables, such as autoregulation, comorbidities, and cerebral ischemic thresholds, it is possible for patients receiving high-quality cardiopulmonary resuscitation (CPR) to maintain consciousness
• CVPertaining to the heart and blood vessels that make up the circulatory system.
• CardiovascularPertaining to the heart and blood vessels that make up the circulatory system.
• CVDA general term referring to conditions affecting the heart (cardio) and blood vessels (vascular system). May also simply be called heart disease. Examples include coronary artery disease, valve disease, arrhythmia, peripheral vascular disease, congenital heart defects, hypertension, and cardiomyopathy. Refer to specific conditions for detailed explanations.
• Cardiovascular DiseaseA general term referring to conditions affecting the heart (cardio) and blood vessels (vascular system). May also simply be called heart disease. Examples include coronary artery disease, valve disease, arrhythmia, peripheral vascular disease, congenital heart defects, hypertension, and cardiomyopathy. Refer to specific conditions for detailed explanations.
• Cardiovascular SystemDescribes the heart and all the blood vessels in the body.
• CardioversionA technique of applying an electrical shock to the chest to convert an abnormal heartbeat to a normal rhythm.
• CardioverterDefibrillator that delivers electric shockwaves for treating cardiac arrythmia/ventricular standstill
• Carotid ArteryA major artery (right and left) in the neck supplying blood to the brain
• CPVTA rare inherited heart rhythm disturbance found in young people and children.
• Catecholaminergic Polymorphic Ventricular TachycardiaA rare inherited heart rhythm disturbance found in young people and children.
• CatheterA hollow flexible tube for insertion into a body cavity duct or vessel to allow the passage of fluids or distend a passageway. One use includes the drainage of urine from the bladder through the urethra.
• Catheter Ablation TherapyA procedure used to correct certain types of abnormal heart rhythms.
• Catheter (Cardiac)A 'tube' used to perform heart tests, by introducing it through an artery or vein into the heart (Catheter Tests)
• Catheter (Urinary)A 'tube' used to drain urine from the bladder (often used after heart surgery).
• CatheterisationThe process of inserting a catheter into a vein or artery and guiding it through the heart chambers and surrounding vessels for purposes of examination or treatment.
• CathlabA cath lab is where tests and procedures including ablation, angiogram, angioplasty and implantation of pacemakers/ICDs are carried out
• Cell bodySoma
• CentralIn the context of a central line refers to a line positioned with the tip lying in one of the large veins close to the heart – known as central veins.
• Central LineA line is inserted into the patient in order for liquids/drugs to be passed into their veins.
• CerebellumArea at the back of the brain, below the cerebral hemispheres, involved in the control of movement, co-ordination, posture and balance.
• CerebralConcerning the brain.
• Cerebral angiogramAn X-ray picture of the blood vessels inside the head. A drug is injected via the groin artery to outline these cerebral vessels.
• Cerebral anoxiaA complete interruption of the supply of oxygen to the brain.
• Cerebral EmbolismA blood clot formed in one part of the body and then carried by the bloodstream to the brain, where it blocks an artery
• Cerebral HaemorrhageBleeding within the brain resulting from a ruptured blood vessel, aneurysm, or head injury
• Cerebral hypoxiaA partial interruption of the supply of oxygen to the brain, which becomes inadequate to maintain normal brain function.
• Cerebral ischaemiaA deficiency of blood supply to brain tissue, due to an interruption or reduction of arterial blood flow.
• Cerebral ThrombosisFormation of a blood clot in an artery that supplies part of the brain
• Cerebro-spinal fluidLiquid which fills the ventricles of the brain and surrounds the brain and spinal cord.
• CerebrovascularPertaining to the blood vessels of the brain.
• Cerebrovascular AccidentAlso called cerebral vascular accident, apoplexy, or stroke. Blood supply to some part of the brain is slowed or stopped, resulting in injury to brain tissue
• Cerebrovascular OcclusionThe blocking or closing of a blood vessel in the brain
• CerebrumThis is the largest part of the human brain, which occupies most of the skull cavity. It is made up of the two cerebral hemispheres.
• CholesterolAn oily substance that occurs naturally in the body, in animal fats and in dairy products, and that is transported in the blood. Limited amounts are essential for the normal development of cell membranes. Excess amounts can lead to coronary artery disease.
• Cholesterol Lowering DrugA drug to lower the blood cholesterol level. The most important drug class are the statins.
• ChoreaBrief, involuntary jerky movements involving the limbs and face, seen in a number of brain disorders and following brain injury.
• Chronic Obstructive Pulmonary DiseaseRefers to a number of chronic lung disorders that obstruct airflow. The most common form of COPD is a combination of chronic bronchitis and emphysema.
• COPDRefers to a number of chronic lung disorders that obstruct airflow. The most common form of COPD is a combination of chronic bronchitis and emphysema.
• Chronotropic IncompetenceThe inability of the heart to increase its rate appropriately in response to increased activity or metabolic need, e.g., exercise, illness, etc.
• Cineangiography
  The technique of using moving pictures to show how a special dye passes through blood vessels, allowing doctors to diagnose diseases of the heart and blood vessels.
• Circulatory SystemPertaining to circulation of blood through the heart and blood vessels
• ClaudicationA tiredness or pain in the arms and legs caused by an inadequate supply of oxygen to the muscles, usually due to narrowed arteries or peripheral arterial disease (PAD).
• Clinical PsychologistThis is someone who has a Psychology Degree together with clinical training in psychology.They are trained in research, assessment and the application of different psychological therapies
• ClopidogrelMedication used to prevent clots from forming in the blood vessels
• Closed head injuryDamage to the brain where there is no penetration from the scalp or skull through to brain tissue. Often there is no injury to scalp or skull.
• Closed Heart SurgeryHeart surgery which does not involve operating on the heart's interior and does not need 'heartlung bypass'.
• Clot-BusterA drug used to dissolve a clot in an emergency,for example during a heart attack or stroke. This is called thrombolytic therapy.
• ClubbingSwelling of the tips of the fingers and toes, producing 'finger clubbing' often seen in children who are cyanosed for many years.
• CoarctationAn area of stenosis (narrowing) in an artery (usually the aorta).
• Coarctation of the AortaA congenital heart defect that results in narrowing of the aorta.
• CognitionGeneral term used to cover all areas of intellectual functioning. Includes skills such as thinking, remembering, planning, understanding, concentrating and using language.
• Cognitive Behavourial TherapyCongnitive therapy that is combined with behavioural elements. Patient is encouraged to analyse his or her specific ways of thinking around a problem
• Collateral CirculationBlood flow through small, nearby vessels in response to blockage of a main blood vessel.
• Collateral VesselsNew blood vessels created by the body to try and restore blood flow to an area when the blood vessel(s) that are already there are too small, narrowed, or blocked.
• CollateralsAlternative pathways taken by blood when the normal route through an artery or vein is blocked or has not developed properly. Because of the obstruction the alternative pathways (collateral's) may increase in size and eventually may become nearly as large as the original artery or vein, which is blocked. In some conditions (e.g. Pulmonary Atresia) large collateral's may form before birth, carrying blood to the lung circulation from the aorta (sometimes referred to as MAPCAs Major Aorto(...)
• ComaA state of deep and often prolonged unconsciousness.
• CommissurotomyA procedure used to widen the opening of a narrowed heart valve using a balloon or surgical technique.
• CTAn x-ray technique that uses a computer to create cross-sectional images of the body
• Computed TomographyAn x-ray technique that uses a computer to create cross-sectional images of the body
• ConcussionUnconsciousness after a blow to the head.
• Conducting TissueSpecialised cells or pathways in the heart, which transfer the electrical stimulus from the heart's natural pacemaker to the heart muscle of the atriums and ventricles to signal the heart muscle to contract, for each heart beat.
• Conduction SystemSpecial muscle fibers that conduct electrical impulses throughout the heart muscle
• ConduitA term referring to a tube used to connect one part of the circulation to another surgically (e.g. to bypass an obstructed valve or blocked artery).
• ConfabulationVerbalisations about people, places or events with no basis in reality.
• CongenitalRefers to conditions existing at birth.
• Congenital Heart DefectsMalformation of the heart or of its major blood vessels present at birth
• CHDMalformation of the heart or of its major blood vessels present at birth
• Congenital Heart DiseaseA defect or disease affecting the heart from birth (compare with 'Acquired Heart Disease').
• Congenitally Corrected Transposition of the Great ArteriesIn this complex malformation, the ventricles are on the opposite side of the heart to usual. The atria are connected to the incorrect ventricles and the great arteries also come from the wrong ventricles (transposition). Despite these problems, blood from the lungs passes to the aorta, so the child is not cyanosed. Other heart defects are commonly present (e.g. VSD, valve abnormalities, coarctation, pulmonary stenosis).
• Congestive Heart FailureA condition which occurs when there is a buildup of fluid (i.e. congestion) in the lungs or other organs such as the liver. This congestion usually results when the heart is unable to work efficiently. Children with heart failure may have symptoms such as marked shortness of breath and difficulty with feeding. The term 'heart failure' does not mean that the heart will suddenly stop beating.
• Conscious Having an awareness of one’s environment and one’s own existence, sensations, and thoughts
• Consciousness The state of being conscious; awareness
• Consultant PsychiatristA Consultant Psychiatrist is a trained mental health doctor with additional specialist training in psychiatry. The consultant is medically responsible for the care of people receiving mental health services and also supervises junior doctors
• CPAPAn air pressure in the range 5-30cm. It can be applied to ghe upper airways using a full face mask or a nasal mask only (nCPAP). It is used in HDU's to optimize oxygen delivery to pateints who are being weaned from ventilators and on patients at home with obstructive sleep apnoea.
• Continuous Positive Airways PressureAn air pressure in the range 5-30cm. It can be applied to ghe upper airways using a full face mask or a nasal mask only (nCPAP). It is used in HDU's to optimize oxygen delivery to pateints who are being weaned from ventilators and on patients at home with obstructive sleep apnoea.
• ContracoupBruising of the brain tissue in the side opposite to where the blow was struck.
• ContractionWhen the muscle in the heart wall works (squeezes) to push the blood through the heart and out into the arteries.
• ContracturesJoints and muscles which are not used regularly quickly becoming stiff, and rendering them resistant to stretching.
• ContraindicationA situation in which medication should not be used. For example because of a physical condition, other medications, pregnancy
• Convulsion A violent involuntary contraction of a muscle or muscles.
• Coronary AngiographyOpacification of coronary arteries by injection of iohexol or urograffin or any such contrast agent
• Coronary AngioplastyA procedure in which a narrowed segment of coronary artery is stretched (dilated) by the inflation of a balloon introduced into it by means of cardiac catheterization under x-ray screening. In most cases a stent is then implacted into the angioplasted segment as this improves duration
• Coronary ArteriesTwo arteries arising from the aorta that arch down over the top of the heart and divide into branches. They provide blood to the heart muscle
• Coronary Artery AnomalyA congenital defect in one or more of the coronary arteries of the heart
• CAA
  A congenital defect in one or more of the coronary arteries of the heart
• CABGSurgical rerouting of blood around a diseased vessel that supplies blood to the heart. Done by grafting either a piece of vein from the leg or a piece of the artery from under the breastbone
• Coronary Artery Bypass GraftSurgical rerouting of blood around a diseased vessel that supplies blood to the heart. Done by grafting either a piece of vein from the leg or a piece of the artery from under the breastbone
• CADA narrowing of the arteries that supply blood to the heart. The condition results from a buildup of plaque and greatly increases the risk of a heart attack
• Coronary Artery DiseaseA narrowing of the arteries that supply blood to the heart. The condition results from a buildup of plaque and greatly increases the risk of a heart attack
• CCUA specially equipped unit in a Hospital providing intensive care to patients of coronary artery disease, i.e. myocardial infarction, unstable angina, etc.
• Coronary Care UnitA specially equipped unit in a Hospital providing intensive care to patients of coronary artery disease, i.e. myocardial infarction, unstable angina, etc.
• Coronary Heart DiseaseDisease of the heart caused by a buildup of atherosclerotic plaque in the coronary arteries that can lead to angina pectoris or heart attack
• Coronary ObstructionA partial or complete obstruction (occlusion) of one of the coronary arteries, thereby hindering blood flow to the heart muscle. This can be due to thrombus, embolus, spasm or dissection.
• Coronary OcclusionAn obstruction of one of the coronary arteries that hinders blood flow to the heart muscle
• Coronary RevascularizationThe restoration of blood flow to ischaemic heart muscle by coronary angioplasty and stenting or by a coronary artery bypass graft
• Coronary SpasmA transient partial or complete obstruction (occlusion) of one of the coronary arteries, thereby hindering blood flow to the heart muscle. A rare clinical cause of angina.
• Coronary ThrombosisFormation of a clot in one of the arteries carrying blood to the heart muscle. Also called coronary occlusion
• Cortical blindnessLoss of visual function resulting from damage to the main visual areas, which are located in the occipital lobes at the back of the brain.
• CounsellingCounselling is a talking therapy that usually deals with a recent distressing event.The length of time that counselling is needed varies from person to person.
• Cranial nervesA set of 12 pairs of nerves originating in the brainstem, the oldest part of the brain. Functions of the cranial nerves include control of eye movement and blinking.
• CraniotomySurgical removal of the skull in small pieces.
• Creatinine KinaseA Cardiac enzyme used to diagnose a heart attack.
• Critical Care TeamA team of health professionals who care for critically ill and injured patients. It includes predominantly a critical care intensivist and a critical care nurse but may also include physiotherapists, pharmacists, technicians, social workers and chaplains
• Cross MatchThe test to ensure that blood, for transfusion, is compatible with the patient and will not cause an unwanted reaction.
• CryoablationThe removal of tissue using an instrument called a cold probe.
• CulturesSamples of blood
• CyanosisBlueness of the skin caused by a lack of oxygen in the blood.
• Cyanotic Heart DiseaseA birth defect of the heart that causes oxygen-poor (blue) blood to circulate to the body without first passing through the lungs

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• DeathThe irreversible loss of the capacity for consciousness combined with the irreversible loss of the capacity to breathe. May be diagnosed on cardiovascular (heart) or neurological (brain) criteria.
• Death Rate (age-adjusted)A death rate that has been standardized for age so different populations can be compared or the same population can be compared over time
• Deep Vein ThrombosisA blood clot in a deep vein in the calf (DVT)
• DVTA blood clot in a deep vein in the calf (DVT)
• DefectA physical abnormality, e.g. of the position or structure of the heart or main blood vessels.
• DefibrillationAdminsitration of a controlled electric shock to restore normal heart rhythm in cases of cardiac arrest due to ventricular fibrillation. The apparatus used is a Defibrillator
• Defibrillation Threshold TestingPerformed during ICD implantation, this is an assessment is to confirm appropriate sensing of ventricular fibrillation and to establish an adequate safety margin for defibrillation
• DFTPerformed during ICD implantation, this is an assessment is to confirm appropriate sensing of ventricular fibrillation and to establish an adequate safety margin for defibrillation
• DefibrillatorA device that helps restore a normal heart rhythm by delivering an electric shock.
• DeliriumDelirium is a name for acute confusion. It is sometimes described as like being in a nightmare, but it feels very real to patients. A patient with delirium is hallucinating, which means they can be seeing, hearing, or feeling things that don’t exist outside their mind. They can imagine they are in different situations, and these are often very frightening.
• DemyelinationLoss of the fatty insulating sheath (myelin) surrounding nerve axons, which impairs their function by interfering with their ability to conduct electrical nerve impulses normally.
• DendriteAre appendages that are designed to receive communications from other cells. They resemble a tree-like structure, forming projections that become stimulated by other neurons and conduct the electrochemical charge to the cell body (or, more rarely, directly to the axons)
• DepressionDepression is one of the most common forms of mental health problem and can occur to people of all ages. Symptoms include feelings of despair, hopelessness and worthlessness, an inability to cope, sleep problems and sometimes thoughts of suicide. Often people with depression will complain of physical problems (e.g for example headaches, stomach problems) rather than depression when consulting their GP. Various treatments are available for depression including antidepressant medication,(...)
• DextrocardiaA condition in which the heart lies in the right side (instead of the left) of the chest. The heart may be normal or have other defects.
• DiabetesA disease in which the body doesn’t produce or properly use insulin. Insulin is needed to convert sugar and starch into the energy used in daily life
• DiagnosisIdentifying an illness or problem by its symptoms and signs.
• DiagnosticsData gathered by an ICD or pacemaker to evaluate patient rhythm status, verify system operation, or assure appropriate delivery of therapy options.
• DialysisCirculating a patient’s blood through a machine outside the body to remove toxins, waste products and excess salts from the blood whilst a patient’s own kidneys are unable to do so. Intensive care units commonly offer a gentler/slower version of standard outpatient-type dialysis that is better tolerated by critically ill patients. Maybe colloquially be referred to as ‘filtration’
• DiastoleThe time during which the ventricular heart muscle relaxes after each contraction, between each heart beat.
• Diastolic Blood PressureThe lowest blood pressure measured in the arteries. It occurs when the heart muscle is relaxed between beats
• Diastolic DysfunctionImpairment of heart function due to increased stiffness of the left ventricle, which results in reduced capacity of the heart ot fill with blood duing diastole. The clinical effects of this are described as heart failure with normal ejection fraction (HEF-NEF)
• DiencephalonThe midbrain. This contains discrete nerve centres including the hypothalamus, which controls appetite regulation, sexual arousal, thirst and temperature control, and some aspects of memory. The diencephalon also contains the thalamus, the body's sensory gateway to the brain.
• DietitianA health professional who can advise you on healthy eating and special diets.
• Diffuse axonal injuryWidespread tearing of nerve fibres across the whole of the brain.
• Diffuse brain injuryInjury to cells in many areas of the brain rather than in one specific location.
• DigitalisA medicine made from the leaves of the foxglove plant. Digitalis is used to treat congestive heart failure (CHF) and heart rhythm problems (arrhythmias).
• DigoxinA medicine given to strengthen the heart contraction or reduce the heart rate.
• Dilated CardiomyopathyDisease of your heart muscle where it becomes stretched and thin. This means that its unable to pump blood around your body efficiently
• DiplopiaDouble vision
• Discharge PlanningCarefully considering where the patient’s ongoing care needs can be met when the patient leaves intensive care. Most patients in critical care are discharged to a medical, surgical or another speciality ward; occasionally patients may be discharged directly home.
• DiseaseThis term may be used by the doctors to describe either a congenital defect or an acquired condition, and their effects.
• DisinhibitionDifficulty in controlling urges and impulses to speak, act or show emotions.
• Dissecting AneurysmA condition in which the layers of an artery separate or are torn, causing blood to flow between the layers. Dissecting aneurysms usually happen in the aorta, the large vessel that carries blood from the heart to other parts of the body and can cause sudden death
• DissectionA condition in which the layers of an artery separate or are torn, causing blood to flow between the layers. Dissection most commonly occurs in the aorta and can cause sudden death.
• DiureticA drug that lowers blood pressure by causing fluid loss. Diuretics promote urine production.
• Dizziness A sensation of whirling and a tendency to fall; giddy; vertiginous
• Dizzy Having a whirling sensation in the head with a tendency to fall
• Donor ValvesA heart valve (usually the aortic or pulmonary valve), taken from the heart of a child or adult soon after death, which can be kept sterile and frozen to preserve its structure. It can be used as a replacement for a defective or missing valve in a child or adult having heart surgery.
• Doppler UltrasoundA technology that uses sound waves to assess blood flow within the heart and blood vessels and to identify leaking valves
• Double Inlet Left VentricleA condition in which both atria are connected to the left ventricle. The right ventricle is usually very small.
• DILVA condition in which both atria are connected to the left ventricle. The right ventricle is usually very small.
• Double Outlet Right VentricleA condition where both the aorta and pulmonary artery are connected to the right ventricle. Blood from the left ventricle passes through a VSD to the right ventricle to reach the great arteries.
• DORVA condition where both the aorta and pulmonary artery are connected to the right ventricle. Blood from the left ventricle passes through a VSD to the right ventricle to reach the great arteries.
• Dual-Chamber Pacemaker A pacemaker with two leads (one in the atrium and one in the ventricle) to allow pacing and/or sensing in both chambers of the heart to artificially restore the natural contraction sequence of the heart
• DuctusThe blood vessel connecting the aorta with the pulmonary artery before birth. The full name is 'Ductus Arteriosus'. It usually closes within the early days or weeks after birth. If it remains open after this time it is called a Patent (or Persistent) Ductus Arteriosus (PDA).
• DuraOutermost of the three membranes protecting the brain and spinal cord.
• DyingThe end stage of every persons life, lasting often for several days before the actual death.
• DysarthriaA speech disorder resulting from muscular problems caused by damage to the brain or nervous system.
• DysphagiaDifficulty with swallowing.
• DyspneaShortness of breath.
• DyspnoeaLaboured or difficult breathing. Can be due to an obstruction to the flow of air into and out of the lungs (as in Bronchitis or Asthma)
• DyspraxiaInability to plan and perform purposeful movements, while still having the ability to move and be aware of the movement.

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• Ebstein's AnomalyA form of congenital heart disease affecting the right side of the heart: the tricuspid valve is displaced towards the apex to a varying extent, resulting in impaired right ventricular function. It can cause breathlessness, failure to thrive, cyanosis and abnormalitities of heart rhythm, although it may be asymptomatic, if mild, life expectancy is normal, if severe, corrective surgery may be necessary
• EchocardiogramAn ultrasound scan of the heart. Very high frequency sound waves (ultrasound) are used to create a moving picture of the heart and of blood flowing through it, using a sophisticated computer. This test detects most heart defects and can provide detailed information about the nature and severity of heart problems of many kinds. The test is not painful, but requires that the child remain still for 10 to 20 minutes (sometimes longer). Some children may benefit from mild sedation to help them(...)
• EchocardiographyA method of studying the heart’s structure and function by analyzing sound waves bounced off the heart and recorded by an electronic sensor placed on the chest. A computer processes the information to produce a one-, two- or three-dimensional moving picture that shows how the heart and heart valves are functioning.
• EcholaliaImitation of sounds or words without comprehension. This is a normal stage of language development in infants but is abnormal for adults.
• EctopicsA premature contraction of the atrium or ventricle earlier than the next expected normal sinus or escape rhythm beat. Caused by an abnormal electrical focus.
• EdemaSwelling caused by fluid accumulation in body tissues.
• EfficacyHow well something works.This term is used to refer to treatments in particular.
• EffusionA collection of fluid in an area such as the pericardium or the pleural cavity. Such a collection, if it is large, may lead to buildup of pressure on the heart or lungs, and often results in deterioration in their function, and so it may need to be drained.
• Ejection FractionA measurement of the rate at which blood is pumped out of a filled ventricle. The normal rate is 50% or more
• ECGA test to measure the heart's electrical activity with each heart beat. Wires are attached to the skin of the arms, legs and chest, using soft, stickon discs (called 'electrodes'). A tracing is printed on paper and gives information about the heart rate and regularity, as well as providing data about enlargement of the heart chambers and thickening of heart muscle, which may provide useful information about the nature and severity of heart problems.
• ElectrocardiogramA test to measure the heart's electrical activity with each heart beat. Wires are attached to the skin of the arms, legs and chest, using soft, stickon discs (called 'electrodes'). A tracing is printed on paper and gives information about the heart rate and regularity, as well as providing data about enlargement of the heart chambers and thickening of heart muscle, which may provide useful information about the nature and severity of heart problems.
• Electrocardiogram Treadmill Test (ETT)A recording of the Heart’s Rate and Rhythm while walking on a treadmill.
• ElectrodeThe connector to an external or internal lead conducting an electrical signal to detect or stimulate the heart. Leads are used to produce the Electrocardiogram (ECG). Also when placed internally in the body, leads are used to connect the heart to a Pacemaker, CRT or Implantable Cardioverter Defibrillator (ICD).
• EEGA test that can detect and record the brain’s electrical activity. The test is done by pasting metal disks, called electrodes, to the scalp
• ElectroencephalogramA test that can detect and record the brain’s electrical activity. The test is done by pasting metal disks, called electrodes, to the scalp
• Electromagnetic interferenceElectrical or magnetic sources of interference that may be of concern to those with implanted devices susch as ICD's and pacemakers
• EMIElectrical or magnetic sources of interference that may be of concern to those with implanted devices susch as ICD's and pacemakers
• EPSAn electrophysiological study (EP study) is a test used to evaluate your heart's electrical system and to check for abnormal heart rhythms. Natural electrical impulses coordinate contractions of the different parts of the heart. This helps keep blood flowing the way it should.
• Electrophysiological studyAn electrophysiological study (EP study) is a test used to evaluate your heart's electrical system and to check for abnormal heart rhythms. Natural electrical impulses coordinate contractions of the different parts of the heart. This helps keep blood flowing the way it should.
• Electrophysiological TestingA procedure (invasive or non-invasive) used to detect and give information about abnormal heart rhythms.
• ElectrophysiologyThe study of the electrical properties of cells and tissues
• EmbolismAn embolism is the lodging of an embolus, a blockage-causing piece of material, inside a blood vessel. The embolus may be a blood clot (thrombus), a fat globule, a bubble of air or other gas, or foreign material. An embolism can cause partial or total blockage of blood flow in the affected vessel.
• EmbolusAlso called embolism; a blood clot that forms in a blood vessel in one part of the body and travels to another part.
• A&EEmergency Department, also known as A&E (accident and emergency) a hospital department that assesses and deals with the immediate problems of acutely ill and injured patients
• Emergency DepartmentEmergency Department, also known as A&E (accident and emergency) a hospital department that assesses and deals with the immediate problems of acutely ill and injured patients
• Emotional labilityRapid and drastic changes in emotional state (such as laughing, crying or anger) that are inappropriate.
• EndarterectomySurgical removal of plaque deposits or blood clots in an artery.
• EndocarditisA bacterial infection of the heart’s inner lining (endothelium).
• Endocarditis ProphylaxisUse of antibiotics to prevent endocarditis at times when bacteria may be expected to enter the bloodstream (e.g. dental extractions or surgery on nose, throat, mouth or bowel). See Protocol for prevention.
• EndocardiumThe smooth membrane covering the inside of the heart. The innermost lining of the heart.
• EndomyocarditisAn acute or chronic inflammatory disorder of the muscle an lining membrane of the heart.
• EndotheliumThe smooth inner lining of many body structures, including the heart (endocardium) and blood vessels.
• Endotracheal TubeThis tube is inserted through either the patient's nose or throat into the windpipe and is sometimes referred to as an ET tube.
• Enlarged HeartA state in which the heart is larger than normal because of heredity, long-term heavy exercise, or diseases and disorders such as obesity, high blood pressure, and coronary artery disease
• EnzymeA complex chemical capable of speeding up specific biochemical processes in the body.
• EpicardiumThe thin membrane covering the outside surface of the heart muscle.
• EpilepsyThere are many varied presentations. Seizure or fit activity involving parts of or the complete body.
• EstrogenA female hormone produced by the ovaries that may protect premenopausal women against heart disease. Estrogen production stops after menopause.
• Estrogen Replacement TherapyHormones that some women may take to offset the effects of menopause
• ERTHormones that some women may take to offset the effects of menopause
• Evoked potentialsElectrical responses of the brain to stimulation, recorded from the scalp.
• Executive functionsThe ability to think and reason, to synthesize and integrate complex information and make considered judgements and decisions about what to do in a particular situation.
• Exercise Stress TestA common test to help doctors assess blood flow through coronary arteries in response to exercise, usually walking, at varied speeds and for various lengths of time on a treadmill. A stress test may include use of electrocardiography, echocardiography, and injected radioactive substances. Also called exercise test, stress test, nuclear stress test, or treadmill test
• Exercise Tolerance TestFormal exercise test whilst monitoring the patient, blood pressure and ECG using either a treadmill or bicycle ergometer. Used for detecting coronary ischaemia, arrhythmias and level of cardiovascular fitness.
• ECMOCirculating a patient’s blood to a machine outside the body that adds oxygen to – and removes waste carbon dioxide from – the bloodstream. Specialised service in a handful of centres across the UK. Patient’s often have to travel to a different ICU to receive the therapy.
• Extra-Corporeal Membrane OxygenationCirculating a patient’s blood to a machine outside the body that adds oxygen to – and removes waste carbon dioxide from – the bloodstream. Specialised service in a handful of centres across the UK. Patient’s often have to travel to a different ICU to receive the therapy.
• ExtubationRemoving a patient’s endotracheal (breathing) tube to see if they can breathe without the aid of a ventilator. Often follows a sedation-hold (see below).
• EMDREMDR is a relatively new treatment to help people deal with trauma. It involves elements of exposure therapy (see definition) and cognitive behavioural therapy (see definition), combined with other techniques.
• Eye Movement Desensitisation and ReprocessingEMDR is a relatively new treatment to help people deal with trauma. It involves elements of exposure therapy (see definition) and cognitive behavioural therapy (see definition), combined with other techniques.

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• FacemasksUsed to deliver oxygen therapy and breathing support for the awake patient.
• Fallots TetralogyA common heart defect associated with cyanosis. There are four parts to the defect (Tetra = four). The name 'Fallot' refers to the French doctor who described the features of the defect.
• Familial HypercholesterolemiaA genetic predisposition to dangerously high cholesterol levels
• Fatty AcidsSubstances that occur in several forms in foods; different fatty acids have different effects on lipid profiles
• Fever A rise in body temperature above the normal
• FibrateA drug used to bring down cholesterol and triglyceride levels in your blood.
• FibrillationRapid, uncoordinated contractions of individual heart muscle fibers. The heart chamber involved can’t contract all at once and pumps blood ineffectively, if at all.
• First AidProcedures used in an emergency to help a wounded or ill patient before the arrival of an emergceny medical person/doctor or admission to hospital.
• First-degree Heart BlockOccurs when an electrical impulse from the heart’s upper chambers (the atria) is slowed as it moves through the atria and atrioventricular (AV) node
• Fluid BalancePatients in ICU are often unable to control their own fluid balance. They may be dehydrated from lack of food and drink, vomiting or diarrhoea
• FlutterThe rapid, ineffective contractions of any heart chamber. A flutter is considered to be more coordinated than fibrillation.
• Focal brain injuryInjury restricted to one region (as opposed to diffuse).
• Fontan OperationAn operation to connect the main veins from the systemic circulation (SVC and IVC) to the lung arteries. Blood then flows directly into the lung circulation, after returning from the body, without going through the right ventricle as would happen in a normal heart. This operation is named after a French surgeon Francis Fontan.
• Foramen OvaleThe hole between the two atriums present at birth.
• Frontal lobesThe largest lobes of the brain, occupying the front part of the cerebral hemispheres. As well as containing the areas controlling voluntary movement and speech production, the frontal lobes are involved in the executive functions of thinking and reasoning, the integration of complex information, judgement, decision-making and planning for the future. They also have an important role in social behaviour, personality and emotion.
• Fusiform AneurysmA tube-shaped aneurysm that causes the artery to bulge outward. Involves the entire circumference (outside wall) of the artery

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• GastrostomyThe creation of an opening into the stomach for the administration of foods and fluids when swallowing is impossible.
• Gated Blood Pool ScanAn x-ray analysis of how blood pools in the heart during rest and exercise. The test uses a radioactive substance to tag red blood cells to allow doctors to estimate the heart’s overall ability to pump and its ability to compensate for one or more blocked arteries. Also called MUGA (multiple gated acquisition scan) or nuclear ventriculography
• General PractitionerYour family doctor. It is helpful to first visit your GP when your heart child is reasonably well. Then, when your child is ill, the doctor can see how skin colour, breathing, heart sounds, etc. have changed.
• Genetic TestingBlood tests that study a person’s genes to find out if he or she is at risk for certain diseases that are passed down through family members
• GCSA scoring system used to describe a patient’s level of consciousness/unconsciousness. The normal score is 15. The lowest score of 3 indicates deep unconsciousness/unresponsive patient.
• Glasgow Coma ScaleA scoring system used to describe a patient’s level of consciousness/unconsciousness. The normal score is 15. The lowest score of 3 indicates deep unconsciousness/unresponsive patient.
• GlutamateThe major excitatory neurotransmitter in the brain. Excessive glutamate release (or cascade) following TBI can be a major cause of nerve cell death in the second injury.
• Glyceryl Trinitrate (Nitroglycerin)A drug that dilates blood vessels and is used mainly to prevent and treat angina. Side effects may include flushing, headache, and fainting. Glyceryl trinitrate is also applied topically in the treatment of anal fissures.
• GTNA drug that dilates blood vessels and is used mainly to prevent and treat angina. Side effects may include flushing, headache, and fainting. Glyceryl trinitrate is also applied topically in the treatment of anal fissures.
• GraftTransplanted tissue from one area of the body to another (As in use of a saphenous vein graft from the leg to bypass a coronary artery blockage during coronary artery bypass surgery).
• Graham Steell MurmurA soft high-pitched heart murmur best heard over the second left intercostal space in early diastole. It is a sign of Pulmonary Regurgitation
• Grey matterNerve cell bodies in the brain, which have a greyish appearance and make up the cerebral cortex.
• GuidelineA recommendation of good practice usually based on research evidence
• GuidewireA small, bendable wire that is threaded through an artery; it helps doctors position a catheter so they can perform angioplasty or stent procedures.
• GyrusA ridge of the cerebral cortex.

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• HaematomaA collection of blood forming a definite swelling which compresses and damages the brain around it.
• HaemofilterThis is a machine that helps the kidneys work. It removes blood from a vein through a tube then pumps it through a filter to remove excess fluid and waste products. Once the waste products are cleaned out of the blood, the blood is returned to the patient.
• HaemoglobinThe red coloured pigment in red blood cells that binds avidly to oxygen. Composed of protein and iron. Allows red blood cells to carry oxygen to a patient’s organs & tissues.
• Haemorrhage Profuse bleeding from ruptured blood vessels
• Head injury - mild/minorMay causes brief loss of consciousness for 15 minutes or less with a period of post-traumatic amnesia of less than 1 hour.
• Head injury - moderateDefined as being a condition where the patient has been in a coma for 6 hours, and a period of post-traumatic amnesia of up to 24 hours.
• Head injury - severeDefined as being a condition where the patient has been in a coma for 6 hours or more, or a post-traumatic amnesia of 24 hours or more.
• HeartThe heart is a muscular organ which pumps blood through the blood vessels of the circulatory system. to provide the body with oxygen and nutrients, as well as assists in the removal of metabolic wastes. The heart is located in the middle compartment of the chest. The heart has 2 pumps, each composed of one atrium and one ventricle with the contraction sequence controlled by it’s own electrical system. There are heart valves ensuring that flow is only in one direction.
• Heart AgeA scoring system that uses biometric data to calculate the risk of a heart attack for an individual and expresses this risk in terms of notional heart age
• Heart Assist DeviceA mechanical device that is surgically implanted to ease the workload of the heart
• HADA mechanical device that is surgically implanted to ease the workload of the heart
• Heart AttackDeath of, or damage to, part of the heart muscle caused by a lack of oxygen-rich blood flowing to the heart
• Heart BlockA condition in which there is damage to, or a defect or disease affecting the conducting tissue which carries the electrical stimulation for the contractions of the heart. If the condition is 'partial', the heart rhythm may be normal for much of the time, but in more severe forms, especially when 'complete', the heart may beat very slowly and become seriously ineffective. A patient with this problem may need an artificial pacemaker.
• Heart FailureSee 'Congestive Heart Failure'. A condition in which the pumping action of the heart is inadequate due to damaged heart valves, ventricular muscle or both. This results in back pressure of blood, with congestion or organs
• HFSee 'Congestive Heart Failure'. A condition in which the pumping action of the heart is inadequate due to damaged heart valves, ventricular muscle or both. This results in back pressure of blood, with congestion or organs
• Heart Failure with Preserved Ejection FractionWhen the ejection fraction (pumping action) of the left ventricle is normal but filling of this chamber is impaired. This can lead to heart failure. Can present gradually or acutely…Chronic and Acute Heart failure respectively.
• Heart-Lung BypassA technique employed for nearly all open heart operations by which the circulation is supported by a machine. The machine takes over the function of both the heart and the lungs (the 'heartlung bypass machine'), while the surgeon opens the heart to perform an operation inside it (see 'Open Heart Operation' And 'Bypass Operation').
• Heart-Lung MachineAn apparatus that oxygenates and pumps blood to the body during open heart surgery; see cardiopulmonary bypass
• Heart ManualA Manual given to patients which details their cardiac rehabilitation programme after heart illness. Sometimes used as an alternative to exercise class based rehabilitation.
• Heart MurmurAn abnormal heart sound caused by turbulent blood flow. The sound may indicate that blood is flowing through a damaged or overworked heart valve, that there may be a hole in one of the heart’s walls, or that there is a narrowing in one of the heart’s vessels. Some heart murmurs are a harmless type called innocent heart murmurs
• Heart RateThe number of times the heart beats in a minute.
• Heart RhythmThe pattern of the heartbeats. The heart should beat regularly with an even space between each heartbeat.
• Heart SoundsThe sounds (heard normally with the doctor's stethoscope) which result from closure of the heart valves with each heart beat. The two atrioventricular valves (mitral valve and tricuspid valve) close at the beginning of each beat, producing the 'first heart sound'. The two arterial valves (pulmonary valve and aortic valve) close at the end of each heart beat, producing the 'second heart sound'.
• Heart Support GroupA group of people who have gone through similar heart disease experiences who meet, talk and give each other support.
• Heart TransplantOperation which involves replacing the diseased heart with the healthy heart of a donor.
• Heart Valve DiseaseIf one or more of your heart valves becomes damaged or diseased, it can affect the flow of blood through your heart. If this causes you problems, it may need treatment with medicines or surgery.
• Helicopter-Based Emergency ServiceA fast method for the provision of first aid and the rapid transport of the seriously injured (primary use) or the critically ill (secondary use) to a hospital.
• HEMSA fast method for the provision of first aid and the rapid transport of the seriously injured (primary use) or the critically ill (secondary use) to a hospital.
• HematocritA measure of the percentage of red blood cells in a given amount (or volume) of whole blood.
• HemochromatosisA disease in which too much iron builds up in your body (iron overload). Too much iron in the heart can cause irregular heartbeats (arrhythmias) and heart failure. Too much iron in the pancreas can lead to diabetes.
• Hemodynamics The forces involved in circulating blood through the cardiovascular system. The heart adapts its hemodynamic performance to the needs of the body, increasing its output of blood when muscles are working and decreasing output when the body is at rest
• HeparinA medicine used to slow the clotting of the blood.
• HeredityThe genetic transmission of a particular quality or trait from parent to child.
• Hibernating MyocardiumAn area of the heart muscle subject to critical coronary ischaemia sufficient to cause reversible impairment of function but insufficient to result in death of the muscle. Also known as viable myocardium, it is detected by MRI scanning of the heart
• High Blood PressureA chronic increase in blood pressure above its normal range
• High Density LipoproteinA component of cholesterol, HDL helps protect against heart disease by promoting cholesterol breakdown and removal from the blood; hence, its nickname “good cholesterol”
• HDLA component of cholesterol, HDL helps protect against heart disease by promoting cholesterol breakdown and removal from the blood; hence, its nickname “good cholesterol”
• HDUA hospital unit that provides specialist nursing care of seriously ill patients. The level of care given is greater that that available on a general wards but less than in intensive therapy/care units
• High Dependency UnitA hospital unit that provides specialist nursing care of seriously ill patients. The level of care given is greater that that available on a general wards but less than in intensive therapy/care units
• HippocampusA structure on the inner surface of the temporal lobes, which is made up mainly of grey matter and has an important role in memory processes. Damage to the hippocampus may lead to memory problems.
• Holter MonitorA portable device for recording heartbeats over a period of 24 hours or more
• HomeostasisThe ability or tendency of an organism or cell to maintain internal equilibrium by adjusting its physiological processes. For example, sweating when hot in order to keep the core body temperature at 98.6 degrees maintains homeostasis.
• HomocysteineAn amino acid (one of the building blocks that makes up a protein) normally found in small amounts in the blood. Too much homocysteine in the blood may promote the buildup of fatty plaque in the arteries. For some people, high homocysteine levels are genetic. For others, it is because they do not get enough of certain B vitamins in their diet. (Common misspelling: homocystine)
• HomograftUsually refers to a replacement heart valve which comes from the heart of a 'donor'. The valve is not subject to rejection and does not require anti-rejection drugs. Such valves may function better than an artificial valve and do not necessitate anti-coagulant medications,but they do not last as well as artificial valves.
• Hormone replacement therapyHormones that some women may take to offset the effects of menopause
• HRTHormones that some women may take to offset the effects of menopause
• HormonesChemicals released into the bloodstream that control different functions in the body, including metabolism, growth, sexual development, and responses to stress or illness.
• Hyper
  Prefix meaning larger or more than usual.
• Hyperbaric oxygen therapyA specialized treatment sometimes used in severe anoxic states - particularly after carbon monoxide poisoning - which involves giving pure oxygen at increased pressure in a hyperbaric chamber.
• HypertensionHigh blood pressure.
• Hypertrophic CardiomyopathyAbnormally thickened and enlarged heart muscle that can cause impeded blood flow as well as lethal arrhythmias. Frequently due to a genetic abnormality.
• Hypertrophic Obstructive CardiomyopathyAn overgrown heart muscle that creates a bulge into the ventricle and impedes blood flow
• HOCMAn overgrown heart muscle that creates a bulge into the ventricle and impedes blood flow
• HypertrophyEnlargement of tissues or organs because of increased workload.
• Hyperventilate To breathe in an abnormally deep, long, and rapid manner, sometimes resulting in cramp and dizziness.
• HyperventilationRapid breathing usually caused by anxiety. People feel like they can’t get enough air, so they breathe heavily and rapidly, which can lead to numb or tingly arms and legs, or fainting.
• Hypervigilance Hypervigilance is a state of increased alertness. If you’re in a state of hypervigilance, you’re extremely sensitive to your surroundings. It can make you feel like you’re alert to any hidden dangers, whether from other people or the environment. Often, though, these dangers are not real. Hypervigilance can be a symptom of mental health conditions, including anxiety and PTSD.
• HypoPrefix meaning smaller or less than usual.
• HypoglycemiaLow levels of glucose (sugar) in the blood.
• HypokinesiaDecreased muscle movement. In relation to the heart, hypokinesia refers to decreased heart wall motion during each heartbeat. It is associated with cardiomyopathy, heart failure, or heart attack. Also called hypokinesis.
• HypopituitarismThe condition in which the pituitary gland doesn't produce adequate levels of one or more hormones.
• HypoplasticSmaller than normal or underdeveloped.
• Hypoplastic Left Heart SyndromeA condition in which the left side of the heart is poorly developed and unable to pump blood into the systemic circulation effectively.
• Hypoplastic Right Heart SyndromeA condition in which the right side of the heart is poorly developed and unable to pump blood into the pulmonary circulation effectively.
• HypotensionAbnormally low blood pressure.
• HypothalamusA small structure just above the brain stem. The hypothalamus detects levels of hormones in the blood and controls the pituitary gland's release of hormones in order to keep the levels stable (also see pituitary gland).
• Hypotrophic CardiomyopathyA disease in which the heart muscle becomes abnormally thick (hypertrophied), it makes it harder for the heart to pump blood
• HypoxaemiaLow blood oxygen level – one cause of hypoxia
• HypoxiaLess than normal content of oxygen in the organs and tissues of the body.
• Hypoxic-ischaemic injuryDamage caused by an interruption of oxygen supply (hypoxia) linked with a reduction in the blood flow to the brain (ischaemia), such as occurs when the heart stops beating in a cardiac arrest.

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• IdiopathicNo known cause.
• IdioventricularAffecting or peculiar to the ventricles of the heart. The term is most often used to describe the very slow beat of the heart's ventricles under the influence of their own natural subsidiary pacemaker
• ImmunosuppressantsAny medicine that suppresses the body’s immune system. These medicines are used to minimize the chances that the body will reject a newly transplanted organ, such as a heart.
• Impedance PlethysmographyA noninvasive diagnostic test used to evaluate blood flow through the leg
• ICDDevice that terminates an erratic, life-threatening cardiac arrhythmia by delivering a high-energy, direct current, electrical stimulus to cardiac tissue. An ICD is usually implanted in the upper chest or abdominal area.
• Implantable Cardioverter DefibrillatorDevice that terminates an erratic, life-threatening cardiac arrhythmia by delivering a high-energy, direct current, electrical stimulus to cardiac tissue. An ICD is usually implanted in the upper chest or abdominal area.
• Implantable Loop RecorderAn electronic device that is surgically implanted over the chest wall to detect arrhythmias. The ILR can be interogated by remote monitoring.
• ImpulsivityA tendency to rush into something without reflecting or thinking first.
• In-Hospital Cardiac ArrestA cardiac arrest that takes place in a hospital. These are distinguished from other cardiac arrests as the treatment may slightly differ and statisically the survival rate is better than out of hospital events
• IHCAA cardiac arrest that takes place in a hospital. These are distinguished from other cardiac arrests as the treatment may slightly differ and statisically the survival rate is better than out of hospital events
• ISTA condition in which a person's heart rate, at rest and during exertion, is abnormally elevated for no apparent reason. It is defined as a resting heart rate greater than 90 beats per minute on average that can rise to very high levels with even minimal exertion. These inappropriately elevated heart rates are accompanied by symptoms of palpitations, fatigue, lightheadedness, or exercise intolerance.
• Inappropriate Sinus TachycardiaA condition in which a person's heart rate, at rest and during exertion, is abnormally elevated for no apparent reason. It is defined as a resting heart rate greater than 90 beats per minute on average that can rise to very high levels with even minimal exertion. These inappropriately elevated heart rates are accompanied by symptoms of palpitations, fatigue, lightheadedness, or exercise intolerance.
• Incompetent ValveAlso called insufficiency; a valve that is not working properly, causing it to leak blood back in the wrong direction
• Induced ComaSome patients who survive a cardiac arrest are put into what is called an induced coma. This is where the person is given anaesthetic drugs, similar to those given when someone has an operation, to put them temporarily to sleep. This allows the body time to recover from the cardiac arrest. The person will be on a breathing machine (ventilator) to help them breathe.
• Induced HypothermiaInduced hypothermia is called ‘cooling’. The person is cooled, using special blankets, to reduce the demands that their body is making on their brain. This is done where there is a risk that the person who had the cardiac arrest might suffer from damage to their brain, to give their body time to recover.
• InfarctThe area of heart tissue permanently damaged by an inadequate supply of oxygen.
• InfarctionDeath of brain cells resulting from an interruption of their blood supply, as occurs in a stroke.
• InfectionOccurs when a microorganism which can produce disease invades a living tissue. Inflammation is one of the body's reactions to infection.
• Infective EndocarditisAn infection of the heart valves and the innermost lining of the heart (the endocardium), caused by bacteria in the bloodstream
• IVC
  The main vein from the lower part of the body which returns deoxygenated blood to the heart.
• Inferior Vena CavaThe main vein from the lower part of the body which returns deoxygenated blood to the heart.
• InflammationOccurs when a living tissue is reacting to an injury or an infection. Swelling, pain or redness in the tissue are signs of inflammation.
• Innocent MurmurA murmur heard in healthy children, which does not signify any underlying heart disease or defect. These soft heart murmurs are very common and are of no significance.
• InotropesPositive inotropes: Any medicine that increases the strength of the heart’s contraction. Negative inotropes: Any medicine that decreases the strength of the heart’s contraction and the blood pressure in the vessels.
• Integrated Care PathwayIntegrated Care Pathways are a multi-disciplinary and multi-agency approach to mapping patients’ care from admission through to discharge and ongoing care.The aim is pull together all the information into one file that will make it easier for the clinicians involved to give the best care for the patient.
• Intensive Care UnitThe special medical and nursing unit to which patients go for a few hours (or days) after major heart surgery or if they are extremely ill. This area is used to ensure very close monitoring, and ready availability of medical and nursing staff and equipment to cater for any emergency. It is available for seriously ill children, with a wide variety of medical problems, and for those who have had open heart operations, or other major heart surgery, especially if they need 'ventilator' treatment.
• ICUThe special medical and nursing unit to which patients go for a few hours (or days) after major heart surgery or if they are extremely ill. This area is used to ensure very close monitoring, and ready availability of medical and nursing staff and equipment to cater for any emergency. It is available for seriously ill children, with a wide variety of medical problems, and for those who have had open heart operations, or other major heart surgery, especially if they need 'ventilator' treatment.
• IntensivistA critical care physician whose medical practice is focused entirely on the care of critically ill and injured patients.
• Internal Mammary ArteryA durable artery in the chest wall often used as a bypass graft in coronary artery bypass surgery
• Interrupted Aortic ArchA condition in which the upper and lower aorta are completely separated (a severe form of coarctation). A large VSD is nearly always present.
• Interventional CardiologyA subspeciality of cardiology concerned with the treatment of heart conditions using cardiac catherization techniques under local anaesthetic and X-ray control, including percutaneous coronary intervention and percutaneous balloon mitral valvuloplasty
• Interventional ProceduresProcedures of this type may be used to stretch open a narrow valve or blood vessel, using a catheter with an inflatable balloon (Illustration). Alternatively, a tiny 'spring coil' may be inserted to block off an abnormal and unwanted blood vessel (Illustration), or an expanding plug (usually referred to as a 'device') may be placed to close a hole such as an ASD or VSD.(Illustration)
• Intracranial pressure monitorA monitoring device to determine the pressure within the brain. It consists of a small tube (catheter) in contact with the pulsing brain or the fluid cavity within it. ICP is measured by means of a metal screw or a plastic catheter connected to an electronic measuring device.
• IntramuscularInto the muscle.
• Intravascular EchocardiographyA combination of echocardiography and cardiac catheterization. A miniature echo device on the tip of a catheter is used to generate images inside the heart and blood vessels
• Intravascular UltrasoundA combination of echocardiography and cardiac catheterisation. A miniature utrasound device on the tip of a catheter is used to generate images inside the heart and blood vessels.
• IntraveneousInto or within a vein
• Intravenous DripA method of providing medications, fluids or nutrition into a vein. The fluid usually flows from a polythene bag or bottle and can be seen to 'drip' into a small container (chamber), which is connected by a tube to a cannula in the vein. Most children will have a 'drip' following an anaesthetic or after heart surgery. In small babies and in children who need continuous medications by 'drip', the medications may be given by a motorised syringe pump, which controls the rate of administration(...)
• IVA method of providing medications, fluids or nutrition into a vein. The fluid usually flows from a polythene bag or bottle and can be seen to 'drip' into a small container (chamber), which is connected by a tube to a cannula in the vein. Most children will have a 'drip' following an anaesthetic or after heart surgery. In small babies and in children who need continuous medications by 'drip', the medications may be given by a motorised syringe pump, which controls the rate of administration(...)
• Introducer SheathA catheter-like tube that is placed inside a patient’s vessel during an interventional procedure to help the doctor with insertion and proper placement of the actual catheter
• IntubationPlacing an endotracheal (breathing) tube into a patient’s windpipe – usually via their mouth. Patients are usually sedated for this procedure.
• IschemiaDecreased blood flow to an organ, usually due to constriction or obstruction of an artery.
• Ischemic Heart DiseaseAlso called coronary artery disease and coronary heart disease, this term is applied to heart problems caused by narrowing of the coronary arteries, thereby causing a decreased blood supply to the heart
• Ischemic StrokeA type of stroke that is caused by blockage in a blood vessel
• Isosorbide MononitrateA drug used to help prevent angina attacks and sometimes used in the treatment of heart failure.

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• JaundiceYellow/green discolouration of a patient’s skin eyes and other tissues as a result of a raised bilirubin level. Bilirubin is a waste product of expired red blood cells (red blood cells last around 120 days and then need to be disposed of). Bilirubin is normally processed by the liver before being excreted in faeces and urine. Jaundice may arise from abnormal red blood cell breakdown
• Jaw ThrustA manoeuvre for opening the airway of an unconscious patient. The flats of the hands are placed on the cheeks with the fingers hooked uner the angles of the jaw so that the jaw can be pulled upwards to seperate the tongue from the back of the pharynx.
• JouleThe SI unit of work or energy, equal to the work done when the point of application of a force of 1 newton is displaced through a distance of 1 metre in the driection of the force
• Jugular VeinsThe veins that carry blood back from the head to the heart

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• KetoacidosisAbnormally acidic blood due to the accumulation of biological acids called ketone bodies. Most commonly occurs in diabetic patients who stop taking/absorbing their insulin or develop an intercurrent illness. May also arise due to starvation.

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• Laryngeal MaskAn airway tube with an elliptical inflatable cuff at one end for the insertion into the mouth of a patient requiring artificial ventilation.
• Lead Thin, insulated cable that conducts energy and carries electrical signals to and from the heart.
• Leaky ValveSee 'Incompetent'.
• Left AtriumThe upper left-hand chamber of the heart. It receives oxygen-rich (red) blood from the lungs via the pulmonary veins, and then sends this blood to the left ventricle via the mitral valve.
• Left Bundle Branch Blockan abnormality of the electrical conducting system of the heart. There are two main conducting pathways in the heart, the left and the right bundle. In LBBB, the left conducting pathway no longer functions so electrical conduction is maintained through the right bundle. LBBB is more common in structural abnormalities of the heart such as in heart muscle conditions, high blood pressure or coronary artery narrowing.
• LBBBan abnormality of the electrical conducting system of the heart. There are two main conducting pathways in the heart, the left and the right bundle. In LBBB, the left conducting pathway no longer functions so electrical conduction is maintained through the right bundle. LBBB is more common in structural abnormalities of the heart such as in heart muscle conditions, high blood pressure or coronary artery narrowing.
• LCSDA surgical antiadrenergic intervention with a strong antiarrhythmic effect, supported by preclinical as well as clinical data. The mechanism of action of LCSD in structurally normal hearts with increased arrhythmic susceptibility (such as those of patients with channelopathies) is not limited to the antagonism of acute catecholamines release in the heart. denervation of the left cardiac sympathetic nerves has been successfully used to decrease the frequency of potentially lethal(...)
• Left Cardiac Sympathetic DenervationA surgical antiadrenergic intervention with a strong antiarrhythmic effect, supported by preclinical as well as clinical data. The mechanism of action of LCSD in structurally normal hearts with increased arrhythmic susceptibility (such as those of patients with channelopathies) is not limited to the antagonism of acute catecholamines release in the heart. denervation of the left cardiac sympathetic nerves has been successfully used to decrease the frequency of potentially lethal(...)
• Left VentricleThe lower left-hand chamber of the heart. It receives oxygen-rich (red) blood from the left atrium and pumps it into the aorta via the aortic valve. The blood in the aorta is then distributed to all parts of the body.
• Left Ventricular Assist DeviceA mechanical device that can be placed outside the body or implanted inside the body. An LVAD does not replace the heart—it “assists” or “helps” it pump oxygen-rich blood from the left ventricle to the rest of the body
• Left Ventricular DysfunctionDescribes the status of the left ventricle when it is not pumping or filling correctly.
• Left Ventricular FailureCongestion and fluid accumulation affect the lungs, resulting in pulmonary oedema. Patient suffers breathlessness, cough and orthopnoea. There is reduced flow of arterial blood from the heart which in extreme cases results in peripheral circulatory failure.
• Left ventricular hypertrophy (LVH)When the left ventricle is too thick walled. Most commonly due to hypertension but also cab be due to aortic valve disease or cardiomyopathy.
• Left Ventricular NoncompactionA condition of the heart where the walls of the left ventricle (the bottom chamber of the left side of the heart) are non-compacted. This causes channels to form in the heart muscle, called trabeculations. This gives the left ventricle a characteristic 'spongy' look (a bit like honeycomb). Although it usually affects the left ventricle, it can also affect the right ventricle
• LVNCA condition of the heart where the walls of the left ventricle (the bottom chamber of the left side of the heart) are non-compacted. This causes channels to form in the heart muscle, called trabeculations. This gives the left ventricle a characteristic 'spongy' look (a bit like honeycomb). Although it usually affects the left ventricle, it can also affect the right ventricle
• LesionAn injury or wound. An atherosclerotic lesion is an injury to an artery due to hardening of the arteries.
• Levels of careUsed as a descriptor for the dependency of a hospitalised patient. Level 0 refers to standard ward-based care. Level 1 refers to ward-based care plus additional support e.g. continuous ECG monitoring. Level 2 refers to one invasive organ support therapy excluding invasive ventilation (traditionally called HDU). Level 3 refers to invasive ventilation alone or 2+ other invasive organ support therapies (traditionally called ICU).
• Limbic systemA group of deep cortical structures connected to the hypothalamus, governing memory, emotions and basic drives, including sex drive.
• LipidA fatty substance that is insoluble (cannot be dissolved) in the blood.
• LipoproteinA lipid surrounded by a protein; the protein makes the lipid soluble (can be dissolved) in the blood.
• Locked in systemA condition in which the patient is awake and retains the ability to sense and perceive, but is unable to communicate except by limited eye movements. This is due to the motor nervous system being paralysed. It can sometimes be confused with persistent vegetative state.
• LocumA temporary health or social care professional.This person does not have a permanent contract with the Trust.
• Long QT SyndromeProlongation of the Q-T interval on the elctrocardiogram. It indicates susceptability to ventricular tachycardia, ventricular fibrillation, and sudden death. It may be familial or caused by certain drugs (sotalol, amiodarone, certain antipsychotic drugs) A condition affecting the electrical pathways of the heart.
• LDLThe body’s primary cholesterol-carrying molecule. High blood levels of LDL increase a person’s risk of heart disease by promoting cholesterol attachment and accumulation in blood vessels; hence, the popular nickname “bad cholesterol”
• Low Density LipoproteinThe body’s primary cholesterol-carrying molecule. High blood levels of LDL increase a person’s risk of heart disease by promoting cholesterol attachment and accumulation in blood vessels; hence, the popular nickname “bad cholesterol”
• LumenThe hollow area within a tube, such as a blood vessel.
• LungOne of a pair of organs of respiration, situated in the chest cavity on either side of the heart and enclosed by a serous membrance

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• Magnetic Resonance ImagingA technique that produces images of the heart and other body structures by measuring the response of certain elements (such as hydrogen) in the body to a magnetic field. MRI can produce detailed pictures of the heart and its various structures without the need to inject a dye
• MRIA technique that produces images of the heart and other body structures by measuring the response of certain elements (such as hydrogen) in the body to a magnetic field. MRI can produce detailed pictures of the heart and its various structures without the need to inject a dye
• Maladie de RogerA form of congenital heart disease in which there is a small ventricular septal defect that produces a loud heart murmur. It usually causes no symptoms.
• MannitolA solution which removes water from the brain by accelerating urinary excretion and thus reduces raised intracranial pressure.
• Marfan SyndromeAn inherited condition associated with lax tissues and affecting many parts of the body including the bones, eyes, heart and aorta.
• Maze SurgeryA type of heart surgery that is used to treat chronic atrial fibrillation by creating a surgical “maze” of new electrical pathways to let electrical impulses travel easily through the heart. Also called the Maze procedure
• Mechanical ValveAn artificial valve used to replace a diseased or defective valve, most often the aortic valve. Usually constructed of titanium and pyrolytic carbon. Patients with a mechanical valve require anticoagulation medication to prevent clots from forming on the valve.
• Median SternotomyAn incision in the centre of the chest, from the top to the bottom of the breastbone, used to gain access for most major forms of heart surgery.
• Medical Emergency TeamA team usually consisting of a group of physicians, anaesthetists, and senior nurses, that can be summoned urgently to attend patients with deterioating medical conditions
• MINDVoluntary organisation, registered as a charity that promotes the welfare of those with mental health issues through advice, education, campaigning and the provision of resources.
• Minimally conscious stateA state of profoundly altered consciousness seen following a severe brain injury, in which there is some evidence of minimal awareness, although this is far removed from anything approaching normal appreciation of the surroundings or of what is happening.
• Mitral AtresiaComplete obstruction to the mitral valve.
• Mitral Regurgitation (reflux)Backward leak of circulating blood from left ventricle to left atrium due to failure of the mitral valve to close, or to prolapse or to perforation. The leak can be trivial, mild, moderate, or severe.
• Mitral StenosisA narrowing of the mitral valve, which controls blood flow from the heart’s upper left chamber to its lower left chamber. May result from an inherited (congenital) problem or from rheumatic fever
• Mitral ValveThe valve at the junction of the left atrium with the left ventricle, which controls flow of blood into the ventricle, before each beat, and prevents backflow.
• Mitral Valve ProlapseA condition that occurs when the leaflets of the mitral valve between the left atrium and left ventricle bulge into the atrium and permit backflow of blood. The condition can be associated with progressive mitral regurgitation
• Mitral Valve RegurgitationFailure of the mitral valve to close properly, causing blood to flow back into the heart’s upper left chamber (the left atrium) instead of moving forward into the lower left chamber (the left ventricle)
• Mitral Valve SurgeryThis can take the form of repair, splitting of the valve if narrowed (valvotomy), or valve replacement.
• mm HgAn abbreviation for millimeters of mercury. Blood pressure is measured in units of mm Hg—how high the pressure inside the arteries would be able to raise a column of mercury.
• mmol/lUnits used for measuring the level of different lipids, and many substances including electrolytes. Usually refers to levels in the blood but measurements can be from other body fluids.
• MONAThe standard treatments for acute coronary syndromes
• Morphine, Oxygen, Nitrates, AspirinThe standard treatments for acute coronary syndromes
• MonitorAn electronic device used to record or regulate
• Monophasic DefibrillatorIs a device used to perfom defibrillation for the purpose of turning abnormal ECG rhythm into normal rhythm
• Monounsaturated FatsA type of fat found in many foods but mainly in avocados and in canola, olive, and peanut oils. Monounsaturated fat tends to lower LDL cholesterol levels, and some studies suggest that it may do so without also lowering HDL cholesterol levels
• Morbidity The fact of having a particular disease or illness. Having two diseases or illnesses simultaneously is known as comorbidity. Experiencing three or more at the same time is referred to as multi-morbidity.
• MorphineA potent opioid analgesic used mainly to relieve severe and persistent pain, particularly in the terminally ill patients.
• MortalityThe total number of deaths from a given disease in a population during an interval of time, usually a year.
• Motor cortexThe part of the brain involved in planning and executing voluntary movements. The primary motor cortex lies directly in front of the primary SENSORY CORTEX on the upper surface of the brain.
• Mouth to Mouth ResuscitationA form of artificial respiration performed on an individual who has stopped breathing. Nostrils are pinched closed, head is tilted back, seal is provided by the rescuer between mouths of patient and rescuer, air is blown firlmly and steadily into the lungs of intervals around 3 seconds
• MR-conditional Under specific conditions of use, safe in the MR environment.
• MR Safe Presents no known hazards resulting from exposure to any MRI environment
• MR Unsafe Presents unacceptable risks in the MR environment.
• MUGA ScanMultiple-Gated Acquistion Scan, a technique used in nuclear medicine for studying the left-ventricular function and wall motion of the heart.
• MurmurNoises superimposed on normal heart sounds. They are caused by congenital defects or damaged heart valves that do not close properly and allow blood to leak back into the chamber from which it has come.
• MyelinA fatty insulating sheath, which surrounds nerve axons and improves the efficiency of transmission of the electrical nerve impulses along them.
• Myocardial InfarctionA heart attack. The damage or death of an area of the heart muscle (myocardium) resulting from a blocked blood supply to the area. The affected tissue dies, injuring the heart. Symptoms include prolonged, intensive chest pain and a decrease in blood pressure that often causes shock
• Myocardial IschemiaOccurs when a part of the heart muscle does not receive enough oxygen
• Myocardial Perfusion ScanA method to detct and quantify myocardial ischaemia. An intravenously injected radionuclide that is taken up buy normal heart muscle can be imaged useing a gamma camera.
• Myocardial StunningThe temporary loss of function of an area of heart muscle due to transient blockage of a coronary artery. Typically seen after a Myocardial Infarction that is treated promptly by successful emergency PCI (Percutaneous coronary intervention)
• MyocarditisA rare condition in which the heart muscle becomes inflamed as a result of infection, toxic drug poisoning, or diseases like rheumatic fever, diphtheria, or tuberculosis.
• MyocardiumThe muscular wall of the heart. It contracts to pump blood out of the heart and then relaxes as the heart refills with returning blood.
• MyoclonusSudden, shock-like muscle twitches or jerks, seen in various brain disorders and quite common following severe cerebral anoxia.
• Myxomatous degenerationA connective tissue disorder that causes the heart valve tissue to weaken and lose elasticity.

• n

• Nasal SpecsThis is a way of giving oxygen through tubes that fit into the nostrils.
• Nasogastric tubeThis is a tube that passes into the stomach from one of the nostrils of your nose. Most ICU patients have one of these. It is used to drain the stomach if you are being sick or give food down when possible.
• National Early Warning ScoreThe NEWS is based on a simple aggregate scoring system in which a score is allocated to physiological measurements, already recorded in routine practice, when patients present to, or are being monitored in hospital.
• NEWS2The NEWS is based on a simple aggregate scoring system in which a score is allocated to physiological measurements, already recorded in routine practice, when patients present to, or are being monitored in hospital.
• NebuliserThis makes medicine into an aerosol and helps loosen thick phlegm and open the airways.
• NecrosisRefers to the death of tissue within a certain area.
• Nerve call bodiesThe largest part of a nerve cell. The cell body holds all of the general parts of a cell as well as the nucleus, which is the control centre.
• Neuro-transmittersChemicals made in the nervous system that serve as messengers, aiding or interfering with the functions of the nerve cells.
• Neurocardiogenic SyncopeA recurrent loss of consciouness due to a drop in blood pressure mediated by vasodilatation, bradycardia or a combination of both. They ressemble a simple faint but can be very disabling because they are more frequent and severe.
• Neurogenesis The process by which new neurons are formed in the brain. Neurogenesis is crucial when an embryo is developing, but also continues in certain brain regions after birth and throughout our lifespan
• Neurogenic diabetes insipidusA condition which causes thirst and excessive production of dilute urine due to the pituitary gland not producing enough of the hormone vasopressin (anti-diuretic hormone).
• NeuronA nerve cell.
• NeurosisNeurosis is used to describe anxiety disorders such as anxiety and phobias.
• NicardipineCalcium - channel blocker used to prevent angina and treat hypertension.
• NicotineA chemical found in tobacco smoke, probably harmless, alongside many harmful chemicals in the smoke that cause vascular disease and cancers.
• Nicotine Replacement ProductsProducts containing nicotine (patches, gum, smoke inhalers and nasal sprays) to help you stop smoking.
• NifedipineCalcium - channel blocker used to prevent angina and treat hypertension (high blood pressure) and Raynaud's Phenomenon
• NitroglycerinA medicine that helps relax and dilate arteries; often used to treat cardiac chest pain (angina).
• Non-ST-Segment-Elevation Myocardial InfarctionThe milder form of the 2 types of heart attack, an NSTEMI does not produce an ST-segment elevation on an electrocardiogram. See also STEMI
• NSTEMIThe milder form of the 2 types of heart attack, an NSTEMI does not produce an ST-segment elevation on an electrocardiogram. See also STEMI
• Non Sustained Ventricular TachycardiaAn abnormally fast heartbeat caused by irregular electrical impulses that originate in the lower chambers of the heart (the ventricles). Ventricular tachycardia that stops by itself within 30 seconds is called non-sustained ventricular tachycardia (NSVT). Any ventricular tachycardia is considered a potentially dangerous cardiac arrhythmia. However, because NSVT does not persist, it is substantially less dangerous than a sustained ventricular tachycardia (SVT) and may turn out to be(...)
• NSVTAn abnormally fast heartbeat caused by irregular electrical impulses that originate in the lower chambers of the heart (the ventricles). Ventricular tachycardia that stops by itself within 30 seconds is called non-sustained ventricular tachycardia (NSVT). Any ventricular tachycardia is considered a potentially dangerous cardiac arrhythmia. However, because NSVT does not persist, it is substantially less dangerous than a sustained ventricular tachycardia (SVT) and may turn out to be(...)
• Noninvasive ProceduresAny diagnostic or treatment procedure in which no instrument enters the body
• Nuclear Cardiology
  The study and dianosis of heart disease by the intravenous injection of different types of radionuclide. The radionuclide emits gamma rays, enabling a gamma camera and computer to form an image of the heart.
• Nuclear Medicine ScanA procedure which involves injecting a very tiny dose of a radio isotope (radioactive compound) into a vein and scanning the heart to assess its function or blood flow through it, using a special Xray scanner. The test may give information about heart function, abnormalities in the heart's own blood supply or the significance of septal defects.

• o

• ObesityThe condition of being significantly overweight. It usually applies when a person is 30% or more over ideal body weight. Obesity puts a strain on the heart and can increase the risk of developing high blood pressure and diabetes.
• Occipital lobesArea at the back of the cerebral hemispheres, containing the main visual centres.
• OccludedAn opening, orifice, or passage that is completely blocked. For cardiology this usually relates to a blocked vessel, artery more often than a vein.
• Occluded ArteryAn artery in which the blood flow has been impaired by a blockage
• Occupational TherapistOccupational therapists use purposeful activities to treat people with physical and/or mental health problems. They work as part of a team to identify problems caused by people’s conditions and find ways of coping with these to encourage independence and a better quality of life.
• Occupational TherapyOccupational therapy uses goal-directed activities, appropriate to a person’s age and social role, to restore, develop or maintain the ability for independent living
• OedemaExcess fluid in body tissues, commonly in dependant areas such as ankles
• Off Pump CABGCoronary Artery Bypass Graft performed on a beating heart, ie without using cardiopulmonary bypass (the pump refers to a heart-lung machine)
• Omega 3A type of fatty acid found in fish oils. Eating these can help prevent blood clotting and help reduce triglyceride levels.
• Open head injuryAn injury where there is penetration of the scalp and skull through to brain tissue.
• Open Heart OperationAn operation which requires that the heart be opened in order to perform surgery inside it. These operations almost always necessitate the use of heart lung bypass.
• Open Heart SurgeryAn operation in which the chest and heart are opened surgically while the bloodstream is diverted through a heart-lung (cardiopulmonary bypass) machine
• OrganA part of the body, composed of more that one tissue, that forms a structual unit responsible for a particular function (or functions), examples are The heart, lungs, liver etc
• Out of Body ExperienceA form of derealization in which there is a sensation of leaving one's body, sometimes accompanied by visions of travel. It typically occurs after anaesthesia or severe illness and is often attributed to anoxia of the brain
• Out of Hospital Cardiac ArrestA cardiac arrest that takes place out of hospital.These are distinguished from in hospital cardiac arrests as the treatment may slightly differ and statisically the survival rate is worse
• OHCAA cardiac arrest that takes place out of hospital.These are distinguished from in hospital cardiac arrests as the treatment may slightly differ and statisically the survival rate is worse
• OximetryA method of measuring the oxygen content of blood.
• Oxygen SaturationThe extent to which the haemoglobin is saturated with oxygen. (Haemoglobin is a protein in the red blood cells that binds with oxygen and carries it to the organs and tissues of the body.)

• p

• PacemakerAn electronic device used to stimulate the heart and regulate the heart rhythm. Many children are attached to a pacemaker temporarily after heart surgery, in case their heart rhythm becomes abnormal. Some children need a permanent artificial pacemaker (often because of heart block), in which case the pacemaker is put in, under the skin in the upper abdomen or in front of an armpit, at an operation.
• Pacing LeadThe means to conduct the electrical signals to and from an an electronic device (pacemaker, ICD or CRT). Temporary pacing is sometimes required and this uses an external pacing lead and pacemaker generator box.
• PALSThis is advanced life support for use in severe medical emergencies in children.
• Paediatric Advanced Life SupportThis is advanced life support for use in severe medical emergencies in children.
• PaediatricianA specialist in children's diseases or problems. Some paediatricians are experts in particular types of disease or defects (e.g. Paediatric Cardiologist, or Paediatric Neurologist [specialist in brain and nerve diseases]). Others take a more general interest in the whole development of the child, physically and intellectually, and in a wide range of diseases and problems of infancy and childhood.
• PalpitationAn uncomfortable feeling within the chest caused by an irregular heartbeat.
• PancreasThe organ behind the stomach that helps control blood sugar levels.
• PancreatitisSwelling (inflammation) of the pancreas.
• ParalysisLoss of the ability to move muscles and feel in part of the body or the whole body. Paralysis may be temporary or permanent
• Parietal lobesThe part of each cerebral hemisphere primarily concerned with the perception and interpretation of sensation and movement.
• Parkinson's diseaseA slowly progressive brain disease involving the basal ganglia and causing reduced movement, rigidity and tremor. Damage to the basal ganglia - which can occur in cerebral anoxia - may produce symptoms resembling spontaneously occurring Parkinson's disease.
• Paroxysmal Supraventricular TachycardiaAn occasional rapid heart rate (150-250 beats per minute) that is caused by events triggered in areas above the heart’s lower chambers (the ventricles). See also supraventricular tachycardia (SVT)
• PSVTAn occasional rapid heart rate (150-250 beats per minute) that is caused by events triggered in areas above the heart’s lower chambers (the ventricles). See also supraventricular tachycardia (SVT)
• Passive SmokingWhere non smokers inhale other people’s smoke. Causes the same ill health effects as low cigarette smoking.
• PatentOpen' (as in Patent Ductus Arteriosus).
• PDARefers to the situation when the ductus remains open after the early days or weeks of life, resulting in a shunt of blood between the aorta and the pulmonary artery.
• Patent Ductus ArteriosusRefers to the situation when the ductus remains open after the early days or weeks of life, resulting in a shunt of blood between the aorta and the pulmonary artery.
• PFOA small hole between the atriums, related to failure of the normal Foramen Ovale to close completely after birth. Such a communication is present in about 20% of normal adults and very seldom causes any problem or requires treatment.
• Patent Foramen OvaleA small hole between the atriums, related to failure of the normal Foramen Ovale to close completely after birth. Such a communication is present in about 20% of normal adults and very seldom causes any problem or requires treatment.
• Peer Support When people use their own experiences to help each other. Peer support is non-directive (so it’s not guided by a leader or facilitator) and aims to create an equal power dynamic between people.
• PercutaneousMade, done, or effected through the skin
• Percutaneous Coronary InterventionAny of the noninvasive procedures usually performed in the cardiac catheterization laboratory. Angioplasty is an example of a percutaneous coronary intervention. Also called a transcatheter intervention
• PCIAny of the noninvasive procedures usually performed in the cardiac catheterization laboratory. Angioplasty is an example of a percutaneous coronary intervention. Also called a transcatheter intervention
• Percutaneous Transluminal Coronary AngioplastySee angioplasty
• PCTASee angioplasty
• Peri-Arrest PeriodThe recognized period either just before or just after a full cardiac arrest, when the patient's condition is very unstable and care must be taken to prevent progression or regression into a full cardiac arrest.
• Pericardial EffusionA collection of fluid in the pericardium (sac around the heart). Such a collection, if it is large, may lead to a buildup of pressure on the heart. This often results in deterioration in its function, leading to low blood pressure or heart failure.
• PericardiocentesisA diagnostic procedure that uses a needle to withdraw fluid from the sac or membrane surrounding the heart (pericardium).
• PericardiorrhaphyThe repair of wounds in themembrane surrounding the heart, such as due to injury or surgery.
• PericardiostomyAn operation in which the membranous sac around the heart is opened and the fluid within drained via a tube. It is sometimes used in the treatment of septic pericarditis
• PericarditisInflammation of the outer membrane surrounding the heart. When pericarditis occurs, the amount of fluid between the two layers of the pericardium increases. This increased fluid presses on the heart and restricts its pumping action.
• PericardiumThe outer fibrous sac that surrounds the heart.
• Peripheral Vascular disease (PVD)Disease of the blood vessels that supply blood to the limbs.
• PerseverationThe inappropriate persistence of a response in a current task which may have been appropriate for a former task. Perseveration may be verbal or motoric.
• PerucardiectomySurgical removal of the membranous sac surrounding the heart. It is used in the treatment of chronic constrictive pericarditis and chronic pericardial effusion.
• PharmacistA healthcare professional who ensures that medication that service users receives are safe, effective and appropriate.
• PharmacyThe department that supplies medicines
• PhobiasThis is an extremely common problem in the general population. Phobias are irrational and uncontrollable fears of an object or situation that most people can face without anxiety.The object or situation will trigger feelings of intense panic and the sufferer will go to great lengths to avoid them. Common phobias are fear of flying, spiders and enclosed spaces.
• PhysiotherapistA health professional who helps you to improve mobility and general fitness.
• PiaOne of the three membranes surrounding and protecting the brain and spinal cord. The pia lies below the subarachnoid space in direct contact with the surface of the nerve tissue.
• PICCO
  This is a special line connected to a computer which works out how well your heart is working and responding to fluids.
• Pituitary glandA small structure at the base of the brain which releases a wide variety of hormones that, in turn, control the activity of the body's other hormone glands.
• PlaqueA deposit of fatty (and other) substances in the inner lining of the artery wall characteristic of atherosclerosis.
• PlateletsOne of the three types of cells found in blood; they aid in the clotting of blood.
• PleuraA term which may refer to either (1 ) visceral pleura a membrane which encloses each lung, or (2) parietal pleura a membrane which lines the inside wall of the chest cavity.
• Pleural CavityA potential space between the visceral pleura and parietal pleura. This space normally contains a very thin film of lubricating fluid (compare with 'Pleural Effusion' and 'Pneumothorax').
• Pleural EffusionA collection of fluid in the pleural cavity. Such a collection, if it is large, may lead to a buildup of pressure on the affected lung. This often results in deterioration in its function, with breathlessness and a fall in oxygen levels in the blood.
• Pneumonia A disease of the lungs marked by inflammation, congestion, fever, cough, and difficulty in breathing and caused especially by infection
• PneumothoraxPresence of a collection of air in the pleural cavity. It may result from a tiny puncture in the outside wall of the lung or can follow heart or lung surgery. Such a collection, if it is large, may lead to a buildup of pressure on the affected lung. This often results in deterioration in its function, with breathlessness and a fall in oxygen levels in the blood.
• Polyunsaturated fatThe major fat in most vegetable oils, including corn, safflower, sunflower, and soybean oils. These oils are liquid at room temperature. Polyunsaturated fat actually tends to lower LDL cholesterol levels but may reduce HDL cholesterol levels as well.
• Positron emission tomographyA test that uses information about the energy of certain elements in your body to show whether parts of the heart muscle are alive and working. A PET scan can also show if your heart is getting enough blood to keep the muscle healthy
• PETA test that uses information about the energy of certain elements in your body to show whether parts of the heart muscle are alive and working. A PET scan can also show if your heart is getting enough blood to keep the muscle healthy
• Post-traumatic amnesiaThe period after being unconscious when there may be confused behaviour and no continuous memory of day to day events.
• PTSDPost-traumatic stress disorder (PTSD) is an anxiety disorder that develops following an unusually threatening event. Symptoms include flashbacks, nightmares and intense distress when exposed to an object or situation that is related to the traumatic event.
• Post-traumatic stress disorderPost-traumatic stress disorder (PTSD) is an anxiety disorder that develops following an unusually threatening event. Symptoms include flashbacks, nightmares and intense distress when exposed to an object or situation that is related to the traumatic event.
• POTSA disorder that causes an increased heart rate when a person stands upright
• Postural orthostatic tachycardia syndromeA disorder that causes an increased heart rate when a person stands upright
• PrasugrelMedication that is used to prevent clots forming in blood vessels after a procedure called Percutaneous Coronary Intervention (PCI) (to open a blocked artery in the heart or for a stent insertion)
• PACAre premature heartbeats that are similar to PVCs, but occur in the upper chambers of the heart, an area known as the atria. PACs do not typically cause damage to the heart and can occur in healthy individuals with no known heart disease.
• Premature Atrial ContractionsAre premature heartbeats that are similar to PVCs, but occur in the upper chambers of the heart, an area known as the atria. PACs do not typically cause damage to the heart and can occur in healthy individuals with no known heart disease.
• Premature ventricular contractionAn early or extra heartbeat that happens when the heart’s lower chambers (the ventricles) contract too soon, out of sequence with the normal heartbeat
• PVCAn early or extra heartbeat that happens when the heart’s lower chambers (the ventricles) contract too soon, out of sequence with the normal heartbeat
• PrevalenceThe total number of cases of a given disease that exist in a population at a specific time.
• Primary PCIWhen Percutaneous Coronary Intervention (PCI) is undertaken as the first treatment for a STEMI Heart Attack.
• Prolapse Valve
  Mitral or Aortic. Refers to one of the valve leaflets (flaps) being weaker than normal and tending to fall backwards when the valve closes,resulting often in valve regurgitation.
• Prone positioningPositioning a patient on their front. Sometimes undertaken to help improve a ventilated patient’s oxygen levels.
• ProphylaxisPrevention.For example measures to prevent coronary disease, diabetes and endocarditis.
• ProprioceptionThe sensory awareness of the position of body parts with or without movement.
• PsychiatristA doctor who specialises in the diagnosis and treatment of people who are mentally ill. Psychiatrists have undergone specialist training and may diagnose illness, prescribe medication and other forms of appropriate treatment.They also decide whether to admit people to and discharge from hospital.
• PsychologistPsychologists have skills in the assessment and treatment of mental illness and psychological problems. Unlike psychiatrists they are not medical doctors, their skills include assessing cognitive functions (for example, speech and thought) and providing talking interventions including psychotherapy and counselling.
• PsychotherapistPsychotherapists help people to be in more control of their own lives by exploring emotional difficulties and helping them understand themselves and their relationships with others.They provide consultation and intervention on a one to one basis and in groups.
• PsychotherapyThe treatment of mental health, emotional and personality problems through talking with a therapist. There are many different types of psychotherapy.
• PulmonaryRefers to the lungs and respiratory system.
• Pulmonary ArteryThe main artery carrying blood from the heart to the lungs.
• Pulmonary AtresiaComplete obstruction to the pulmonary valve or pulmonary artery.
• PEA clot that becomes lodged in arteries passing through the lungs. Small PEs may be asymptomatic whilst large ones can be fatal. The clot may originate from a Deep Vein Thrombosis (DVT)
• Pulmonary EmbolismA clot that becomes lodged in arteries passing through the lungs. Small PEs may be asymptomatic whilst large ones can be fatal. The clot may originate from a Deep Vein Thrombosis (DVT)
• Pulmonary OedemaA condition in which there is fluid accumulation in the lungs. Most often caused by an incorrectly functioning heart. Seen in failure of the left ventricle and in congestive heart failure.
• Pulmonary StenosisNarrowing of the pulmonary valve or artery, resulting from (1 ) a congenital defect of the valve leaflets or disease of the valve, or (2) abnormal development (or damage resulting from previous surgery) of the artery or its branches.
• Pulmonary ValveThe valve at the origin of the pulmonary artery, which controls the flow of blood out of the right ventricle and prevents backflow.
• Pulmonary VeinThe blood vessel that carries newly oxygenated blood from the lungs back to the left atrium of the heart
• PulseThe 'beat' felt in an artery, for example in the wrist, groin, neck, or other site and measured in beats per minute. It shows the rate at which the heart is beating, or contracting.
• Pulse OximeterA probe that wraps around a hand or foot connected to a machine which measures how much oxygen the blood is carrying.
• Pulseless Electrical Activity A "Pulseless Electrical Activity" (PEA) arrest is a type of cardiac arrest where the heart's electrical activity is present, but there is no detectable pulse or blood pressure. This means that although the heart generates electrical signals, it does not effectively pump blood to the body's vital organs. Various factors, such as heart attack, respiratory failure, electrolyte imbalances, and drug overdose, can cause PEA arrest. Immediate medical intervention is required to try and restore(...)
• PEA A "Pulseless Electrical Activity" (PEA) arrest is a type of cardiac arrest where the heart's electrical activity is present, but there is no detectable pulse or blood pressure. This means that although the heart generates electrical signals, it does not effectively pump blood to the body's vital organs. Various factors, such as heart attack, respiratory failure, electrolyte imbalances, and drug overdose, can cause PEA arrest. Immediate medical intervention is required to try and restore(...)

• q

• QTCCorrects the QT interval for heart rate extremes
• QT interval correctedCorrects the QT interval for heart rate extremes

• r

• Radial ArteryThe radial artery in the wrist is often used as the preferred entry point for the catheter in a PCI. Also called trans-radial access.
• Radial Artery AccessUsing the radial artery in the wrist as the entry point for the catheter in an angioplasty or stent procedure. Also called transradial access, the transradial approach, or transradial angioplasty
• Radionuclide ImagingA test in which a harmless radioactive substance is injected into the bloodstream to show information about blood flow through the arteries. Damaged or dead heart muscle can often be identified, as can serious narrowing in an artery
• Radionuclide studiesAny of the diagnostic tests in which a small amount of radioactive material is injected into the bloodstream. The material makes it possible for a special camera to take pictures of the heart.
• Radionuclide ventriculographyA diagnostic test used to determine the size and shape of the heart’s pumping chambers (the ventricles).
• Ramiprilto treat high blood pressure and heart failure, also used to help prevent heart, kidney or blood vessel problems in people who are at risk of these
• Rapid Access Chest Pain Service (RACPS)System for referral from Primary Care to Secondary Care for the assessment of chest pain.
• Red Blood CellsThe blood cells which carry oxygen
• RegurgitationBackward flow of blood through a defective heart valve.
• RehabilitationImproving a person’s skills through treatment and/or training to enable them to live a more fulfilling life in the community.
• Rehabilitation ProgrammeA programme to aid recovery following a heart attack, heart surgery, coronary intervention or heart failure in the short and long term. The program provides education about exercise, lifestyle, relaxation and treatments.
• Remote MonitoringA system to enable remote interrogation of pacemakers, ICD and CRT devices from the patient’s home. The results are networked to the relevant cardiac service. Remote monitoring has the potential for early detection of arrhythmias and device malfunction and of saving clinic visits.
• RenalPertains to the kidneys.
• ReprefusionRestoration of blood flow to an organ or tissue. What happens after successful Percutaneous Coronary Intervention or Thrombolysis.
• RespirationBreathing
• RespiratorA machine for helping to maintain adequate respiration when the patient is unable to breath adequately on their own.
• RespiratoryAnything to do with 'respiration'.
• Respiratory arrestBreathing stops and there is no effective supply of fresh oxygen to the blood from the lungs. If breathing is not restored, cardiac arrest will quickly follow, as the heart muscle becomes starved of oxygen.
• Respiratory FailureImplies that the lungs are unable to transfer enough oxygen into the blood, resulting in increasing breathlessness and cyanosis. This may be due to many different diseases affecting the lungs, including severe heart failure, which leads to congestion of the lungs (see 'Congestive Heart Failure').
• RestenosisThe re-closing or re-narrowing of an artery after an interventional procedure such as angioplasty or stent placement
• ResuscitationOften used as a term for ‘Cardiopulmonary Resuscitation’ or ‘CPR’. Attempting to restart someone’s heart using a combination of heart massage, electrical shocks and drugs.
• Retrograde amnesiaThe loss of memory of events for a period prior to the injury.
• RevascularizationA procedure to restore blood flow to the tissues. Coronary artery bypass surgery is an example of a revascularization procedure.
• Rheumatic feverA disease, usually occurring in childhood, that may follow a streptococcal infection. Symptoms may include fever, sore or swollen joints, skin rash, involuntary muscle twitching, and development of nodules under the skin. If the infection involves the heart, scars may form on heart valves, and the heart’s outer lining may be damaged.
• Rheumatic heart diseaseA disease of the heart (mainly affecting the heart valves) caused by rheumatic fever.
• Rib One of a series of long curved bones occurring in 12 pairs in humans and extending from the spine to or toward the sternum. May get injured when receiving CPR
• Right AtriumThe upper right chamber of the heart, which receives oxygen-poor (blue) blood from the body and pumps it to the right ventricle via the tricuspid valve.
• RBBBThis is a blockage of electrical impulses to the heart's right ventricle, the lower-right part of the heart
• Right Bundle Branch BlockThis is a blockage of electrical impulses to the heart's right ventricle, the lower-right part of the heart
• Right VentricleThe lower right chamber of the heart, which receives oxygen-poor (blue) blood from the right atrium and sends it to the pulmonary artery via the pulmonary valve.
• RVADA mechanical device that can be placed outside the body or implanted inside the body. An RVAD does not replace the heart—it “assists” or “helps” it pump oxygen-poor blood from the right ventricle to the lungs
• Right Ventricular Assist DeviceA mechanical device that can be placed outside the body or implanted inside the body. An RVAD does not replace the heart—it “assists” or “helps” it pump oxygen-poor blood from the right ventricle to the lungs
• Right Ventricular FailureThis is when the veins in the neck become engorged and fluid accumulates in the legs (peripheral oedema) or abdominal cavity heart are affected then a combination of the above features is seen. This is usually referred to as Congestive Cardiac Failure (CCF)
• RigidityThis simply means stiffness, resistance to movement.
• Risk factorAn element or condition involving a certain hazard or danger. When referring to heart and blood vessels, a risk factor is associated with an increased chance of developing cardiovascular disease, including stroke.
• Ross OperationAn operation to replace the aortic valve by using the healthy pulmonary valve. The pulmonary valve is itself replaced with a homograft valve.
• RubellaCommonly known as German measles.

• s

• Saccular aneurysmA round aneurysm that bulges out from an artery; involves only part of the circumference (outside wall) of the artery.
• SarcoidosisAn inflammatory disease that starts as tiny, grain-like lumps called granulomas, which most often appear in your lungs or lymph nodes. The granulomas can clump together and form larger lumps that attack other organs. Sarcoidosis often affects your skin, eyes, or liver, but it can lead to heart problems, such as irregular heartbeats (arrhythmias) or restrictive cardiomyopathy.
• Saturated fatType of fat found in foods of animal origin and a few of vegetable origin; they are usually solid at room temperature. Abundant in meat and dairy products, saturated fat tends to increase LDL cholesterol levels, and it may raise the risk of certain types of cancer.
• Second-degree Heart BlockImpulses traveling through the heart’s upper chambers (the atria) are delayed in the area between the upper and lower chambers (the AV node) and fail to make the ventricles beat at the right moment
• Sedation-holdTurning down or turning off a patient’s sedation and observing for signs of wakefulness. May lead to extubation if appropriate.
• Seizure A sudden attack, spasm, or convulsion, as in epilepsy or another disorder
• SensingThe ability of a pacemaker or ICD to recognize and respond to the electrical activity of the heart.
• Sensory cortexThe primary sensory cortex is situated on the upper surface of the cerebrum, directly behind the MOTOR CORTEX. Different areas of the sensory cortex specifically deal with the sensations experienced in different parts of the body.
• SepsisAn overwhelming potentially life-threatening bodily response to infection that can lead to tissue damage
• Septal defectA hole in the wall of the heart separating the atria or in the wall of the heart separating the ventricles.
• SeptumThe muscular wall dividing a chamber on the left side of the heart from the chamber on the right.
• Severe sepsisOverwhelming infection that causes heart blood vessel and cell dysfunction.
• SheathA catheter-like tube that is placed inside a patient’s vessel during an interventional procedure to help the doctor with insertion and proper placement of the actual catheter. Also called an introducer sheath.
• ShockA condition in which body function is impaired because the volume of fluid circulating through the body is insufficient to maintain normal metabolism. This may be caused by blood loss or by a disturbance in the function of the circulatory system.
• Short QT SyndromeThis is a very rare genetic disease of the electrical systme of the heart, associated with risk of abnormal heart rhythms and sudden cardiac death
• SQTSThis is a very rare genetic disease of the electrical systme of the heart, associated with risk of abnormal heart rhythms and sudden cardiac death
• ShuntA connector that allows blood to flow between two locations.
• Sick Sinus SyndromeThe failure of the sinus node to regulate the heart’s rhythm
• SSSThe failure of the sinus node to regulate the heart’s rhythm
• Silent Heart AttackEpisodes of a heart attack that are not accompanied by chest pain
• Silent IschemiaEpisodes of cardiac ischemia that are not accompanied by chest pain
• Sinus BradycardiaA normal but slow heart rhythm.
• Sinus NodeThe “natural” pacemaker of the heart. The node is a group of specialized cells in the top of the right atrium which produces the electrical impulses that travel down to eventually reach the ventricular muscle, causing the heart to contract
• SAThe “natural” pacemaker of the heart. The node is a group of specialized cells in the top of the right atrium which produces the electrical impulses that travel down to eventually reach the ventricular muscle, causing the heart to contract
• Sinus RhythmA normal heart rhythm in which each electrical impulse originates in the sinus node, and proceeds through the rest of the electrical conduction system to cause a normal contraction sequence.
• Sinus TachycardiaA heart rhythm that originates in the sinus node and proceeds through the rest of the electrical conduction system, but is faster than normal.
• SodiumA mineral essential to life found in nearly all plant and animal tissue. Table salt (sodium chloride) is nearly half sodium.
• Somatosensory evoked potentialsElectrical responses of the brain recorded from the scalp following stimulation of nerves in the limbs. Failure to obtain SSEPs in someone in coma following an anoxic brain injury is associated with a poor outcome.
• Source isolationPatients with some infections are routinely cared for ‘in isolation’ to help prevent the spread of infection to other patients. Commonly involves use of physical boundaries by caring for a patient in a side room to the main ward. Staff wear additional personal protective equipment and undertake appropriate hand washing before leaving the area. Side rooms may display alert notices and use directional airflow. Some immunosuppressed patients require ‘reverse isolation’ to protect them from(...)
• SpasticityAn involuntary increase in muscle tone following brain injury, which may produce tightness or stiffness of the limb muscles and interfere with movement and walking.
• Speaking ValveWhen a patient has a tracheostomy they are unable to use their voice. The speaking valve is placed on the tracheostomy and allows the patient to use their voice. The speaking valve is only used as the patient's condition improves.
• SphygmomanometerAn instrument used to measure blood pressure.
• SCAD Is an emergency condition that occurs when a tear forms in a blood vessel in the heart. SCAD can slow or block blood flow to the heart, causing a heart attack, heart rhythm problems (arrhythmias) or sudden death. SCAD most commonly affects women in their 40s and 50s, though it can occur at any age and can occur in men. People who have SCAD often don't have risk factors for heart disease, such as high blood pressure, high cholesterol or diabetes. SCAD can cause sudden death if it(...)
• Spontaneous Coronary Artery Dissection Is an emergency condition that occurs when a tear forms in a blood vessel in the heart. SCAD can slow or block blood flow to the heart, causing a heart attack, heart rhythm problems (arrhythmias) or sudden death. SCAD most commonly affects women in their 40s and 50s, though it can occur at any age and can occur in men. People who have SCAD often don't have risk factors for heart disease, such as high blood pressure, high cholesterol or diabetes. SCAD can cause sudden death if it(...)
• STEMIThe more severe form of the 2 types of heart attack. See also NSTEMI. A STEMI produces a characteristic elevation in the ST segment on an electrocardiogram
• ST-segment-elevation myocardial infarctionThe more severe form of the 2 types of heart attack. See also NSTEMI. A STEMI produces a characteristic elevation in the ST segment on an electrocardiogram
• StatinThe generic name for a family of prescribed cholesterol-lowering drugs.
• Stem cellsSpecial cells in the body that are able to transform into other cells. It is possible for stem cells to transform into heart cells, nerve cells, or other cells of the body, possibly helping to improve the function of failing organs, including the heart.
• StenosisThe narrowing or constriction of an opening, such as a blood vessel or heart valve.
• StentA device made of expandable, metal mesh that is placed (by using a balloon catheter) at the site of a narrowing artery. The stent is then expanded and left in place to keep the artery open.
• SternumThe breastbone.
• StethoscopeAn instrument for listening to sounds within the body.
• Stokes-Adams diseaseAlso called third-degree heart block; a condition that happens when the impulses that pace your heartbeat do not reach the lower chambers of your heart (the ventricles). To make up for this, the ventricles use their own “backup” pacemaker with its slower rate. This rhythm can cause severe dizziness or fainting and can lead to heart failure or death.
• Streptococcal infectionAn infection, usually in the throat, resulting from the presence of streptococcus bacteria
• StreptokinaseA clot-dissolving medicine used to treat heart attack patients.
• StressBodily or mental tension resulting from physical, chemical, or emotional factors. Stress can refer to physical exertion as well as mental anxiety.
• StrokeA sudden disruption of blood flow to the brain, either by a clot or a leak in a blood vessel.
• SubPrefix meaning 'below'
• Sub Aortic StenosisNarrowing below the aortic valve. This usually results from the presence of abnormal tissue or muscle below the valve
• Subarachnoid hemorrhageBleeding from a blood vessel on the surface of the brain into the space between the brain and the skull.
• Subarachnoid spaceThe space between the ARACHNOID membrane and PIA mater. The subarachnoid space is filled with fluid (see: CSF).
• Subclavian arteriesTwo major arteries (right and left) that receive blood from the aortic arch and supply it to the arms.
• S-ICDThe S-ICD system is a Subcutaneous (under the skin) implantable Cardioverter for people at risk of Sudden Cardiac Arrest
• Subcutaneous Internal Cardiac DefibrillatorThe S-ICD system is a Subcutaneous (under the skin) implantable Cardioverter for people at risk of Sudden Cardiac Arrest
• Sublingual
  Under the tongue. Some medicines are taken this way.
• SuctionMechanical removal of mucous from the nose, throat or endotracheal tube with a plastic tube.
• SCAA condition where the heart suddenly stops beating, which results from the problem in the electrical disturbance. This is different from a heart attack
• Sudden Cardiac ArrestA condition where the heart suddenly stops beating, which results from the problem in the electrical disturbance. This is different from a heart attack
• Sudden Cardiac DeathDeath that occurs unexpectedly and instantaneously or shortly after the onset of symptoms. The most common underlying reason for patients dying suddenly is cardiovascular disease, in particular coronary heart disease
• Sudden DeathDeath that occurs unexpectedly and instantaneously or shortly after the onset of symptoms. The most common underlying reason for patients dying suddenly is cardiovascular disease, in particular coronary heart disease.
• SulcusA groove of the cerebral cortex
• Superior Vena CavaThe main vein from the upper part of the body which returns deoxygenated blood to the heart
• SVCThe main vein from the upper part of the body which returns deoxygenated blood to the heart
• SupraPrefix meaning 'above'
• Supra Aortic StenosisNarrowing above the aortic valve. This results from narrowing of the aorta just above the valve.
• Supra Cardiac A term which means 'above the heart', as in 'Supra cardiac Total Anomalous Pulmonary Venous Drainage' ( TAPVD) where the lung veins connect above the heart to the SVC.
• Supraventricular TachycardiaA regular rapid heart rate (150-250 beats per minute) that is caused by events triggered in areas above the heart’s lower chambers (the ventricles); see also paroxysmal supraventricular tachycardia (PSVT)
• SVTA regular rapid heart rate (150-250 beats per minute) that is caused by events triggered in areas above the heart’s lower chambers (the ventricles); see also paroxysmal supraventricular tachycardia (PSVT)
• SyncopeA temporary, insufficient blood supply to the brain which causes a loss of consciousness. Usually caused by a serious arrhythmia.
• SystemicSomething which involves the whole body, e.g. systemic circulation
• SystoleThe time during which the ventricular heart muscle contracts to pump blood
• Systolic blood pressureThe highest blood pressure measured in the arteries. It occurs when the heart contracts with each heartbeat.
• SBPThe highest blood pressure measured in the arteries. It occurs when the heart contracts with each heartbeat.

• t

• TachyPrefix meaning 'fast'
• TachycardiaAccelerated beating of the heart. Paroxysmal tachycardia is a particular form of rapid heart action, occurring in seizures that may last from a few seconds to several days.
• TachypneaRapid breathing.
• Takotsubo cardiomyopathyTakotsubo cardiomyopathy, also known as Broken Heart Syndrome, is a condition where your heart muscle becomes suddenly weakened
• Talking TreatmentsThese are psychological treatments in which improvement in a person’s symptoms or wellbeing is achieved by talking with a therapist or counsellor rather than, or as well as, taking medication.
• TamponadeAlso called cardiac tamponade. A condition in which the heart is compressed or constricted because of a large amount of fluid or blood in the space between the heart muscle and the sac that surrounds the heart (the pericardium).
• Telemetry UnitA small box with wires attached to ECG patches on the chest; used to continuously monitor the rhythm via radio transmission to healthcare professionals for evaluation.
• Temporal lobesThe part of the cerebral hemispheres located under the frontal and parietal lobes, lying inwards of the ears. It has a range of important functions and is involved with hearing and some complex aspects of auditory, language and visual perception, as well as memory and emotion.
• TetralogyUsed to describe a common heart defect with four components (Fallot's Tetralogy)
• Tetralogy of FallotA condition where there is a narrowing in the blood flow from the right ventricle to the lungs, as a consequence of thick muscle underneath the pulmonary valve and a small pulmonary valve. There is also a VSD (hole between the pumping chambers) which causes the oxygen level in the blood to drop.
• TOFA condition where there is a narrowing in the blood flow from the right ventricle to the lungs, as a consequence of thick muscle underneath the pulmonary valve and a small pulmonary valve. There is also a VSD (hole between the pumping chambers) which causes the oxygen level in the blood to drop.
• Thallium-201 stress testAn x-ray study that follows the path of radioactive potassium carried by the blood into heart muscle. Damaged or dead muscle can be defined, as can the extent of narrowing in an artery.
• Therapeutic hypothermiaArtificial cooling may be used to lower the core body temperature, as a means of reducing the metabolism of brain cells and decreasing their oxygen requirement. There is some evidence that this may have a protective effect on the brain following cardiac arrest and in other anoxic states, although this remains controversial.
• Third-degree Heart BlockA serious condition also called Stokes-Adams disease; impulses from the heart’s upper chambers (the atria) are completely blocked from reaching the heart’s lower chambers (the ventricles). To make up for this, the ventricles use their own “backup” pacemaker with its slower rate
• ThrillA medical term used to describe the sensation which can be felt with the hand when it is placed on the chest wall in a patient with a very loud murmur, which is associated with vibrations of sufficient intensity for them to be felt at the surface of the chest.
• ThrombolysisThe breaking up of a blood clot.
• Thrombolytic therapyIntravenous or intra-arterial medicines that are used to dissolve blood clots in an artery.
• ThrombosisA blood clot that forms inside the blood vessel or cavity of the heart.
• ThrombusA blood clot.
• ThyroidA gland located in the front of the neck, just below the voice box.
• TPAA clot-dissolving medicine that is used to treat heart attack and stroke patients
• Tissue plasminogen activatorA clot-dissolving medicine that is used to treat heart attack and stroke patients
• Tissue ValveAn artificial valve, made from animal tissues (pig or cow) and, mounted on a frame with cloth surround, enabling it to be sewn into the heart. There is no requirement for anticoagulation once a tissue valve is inserted unless there is another indication.
• TitrationThis is a method of determining what substances are in a person’s system by testing bodily fluids. It can detect substances such as prescribed medication and also illegal substances such as drugs or alcohol. Dose titration means to slowly increase the dose of a drug to a level that can be maintained.
• TdPTorsades de pointes is a distinctive polymorphic ventricular tachycardia in which the QRS amplitude varies and the QRS complexes appear to twist around the baseline. Torsades de pointes is associated with a prolonged QT interval, which may be congenital or acquired. Torsades de pointes is usually not sustained and terminates spontaneously but frequently recurs unless the underlying cause is corrected. Torsades de pointes may degenerate into sustained ventricular tachycardia or ventricular(...)
• Torsade de pointesTorsades de pointes is a distinctive polymorphic ventricular tachycardia in which the QRS amplitude varies and the QRS complexes appear to twist around the baseline. Torsades de pointes is associated with a prolonged QT interval, which may be congenital or acquired. Torsades de pointes is usually not sustained and terminates spontaneously but frequently recurs unless the underlying cause is corrected. Torsades de pointes may degenerate into sustained ventricular tachycardia or ventricular(...)
• Total Anomalous Pulmonary Venous DrainageA defect in which the pulmonary (lung) veins are connected to veins from the body (i.e. the SVC or IVC) or to the right atrium, instead of returning to the left atrium).
• TAPVDA defect in which the pulmonary (lung) veins are connected to veins from the body (i.e. the SVC or IVC) or to the right atrium, instead of returning to the left atrium).
• TracheostomyThis is where a tube is inserted into the windpipe through an incision in the skin of the neck. It needs a small operation and usually replaces the endotracheal tube and is more comfortable when the sedation is turned off.
• Trans FatCreated when hydrogen is forced through an ordinary vegetable oil (hydrogenation), converting some polyunsaturates to monounsaturates, and some monounsaturates to saturates. Trans fat, like saturated fat, tends to raise LDL cholesterol levels, and, unlike saturated fat, trans fat also lowers HDL cholesterol levels
• Transcatheter aortic valve implantationA minimally invasive procedure to repair a damaged or diseased aortic valve. A catheter is inserted into an artery in the groin and threaded to the heart. A balloon at the end of the catheter, with a replacement valve folded around it, delivers the new valve to take the place of the old. Also called TAVR (Transcatheter aortic valve replacement)
• TAVIA minimally invasive procedure to repair a damaged or diseased aortic valve. A catheter is inserted into an artery in the groin and threaded to the heart. A balloon at the end of the catheter, with a replacement valve folded around it, delivers the new valve to take the place of the old. Also called TAVR (Transcatheter aortic valve replacement)
• Transcatheter InterventionAny of the noninvasive procedures usually performed in the cardiac catheterization laboratory. Angioplasty is an example of a transcatheter intervention. Also called a percutaneous coronary intervention (PCI)
• Transesophageal echocardiographyA diagnostic test that analyzes sound waves bounced off the heart. The sound waves are sent through a tube-like device inserted in the mouth and passed down the esophagus (food pipe), which ends near the heart. This technique is useful in studying patients whose heart and vessels, for various reasons, are difficult to assess with standard echocardiography.
• TransferMoving a patient within or between hospitals. Critical care patients commonly require intra-hospital transfer to radiology for a scan or to theatres for an operation. Patients may require inter-hospital transfer because their nearest intensive care bed is in another hospital or to receive a specialist treatment not available in their original centre.
• TIAAlso known as a mini-stroke. This is a temporary loss of blood supply to the brain which can result in an episode of reversible neurological symptoms. The disease process is similar to that of an ischaemic stroke but the symptoms last minutes to hours. This tends to be a warning and the risk of a full stroke is highest within the first 48 hours. So anyone experiencing a TIA should call 999, in case it does develop into a full stroke, and also so that your future risk can be assessed in hospital
• Transient Ischaemic AttackAlso known as a mini-stroke. This is a temporary loss of blood supply to the brain which can result in an episode of reversible neurological symptoms. The disease process is similar to that of an ischaemic stroke but the symptoms last minutes to hours. This tends to be a warning and the risk of a full stroke is highest within the first 48 hours. So anyone experiencing a TIA should call 999, in case it does develop into a full stroke, and also so that your future risk can be assessed in hospital
• Transoesophageal EchocardiographyA type of ultrasound which produces images of the Heart viewed from the Oesophagus (gullet) and used to assess the structure and function of the heart unimpeded by the bone and lungs which affects imaging through the chest wall (transthoracic echocardiography).
• TransplantationReplacing a failing organ with a healthy one from a donor.
• TranspositionThis is a term used to mean that two structures (usually the aorta and pulmonary artery) are in the opposite position to normal such as in 'Transposition of the Great Arteries' (TGA). See also 'Congenitally Corrected Transposition Of The Great Arteries'.
• Transthoracic EchocardiographyA type of ultrasound which produces images of the heart viewed from the chest wall and used to assess the structure and function of the heart.
• Traumatic Brain InjuryDamage to the brain resulting from a head injury.
• TBIDamage to the brain resulting from a head injury.
• TremorRegular repetitive movements which may be worse either at rest or on attempted movement.
• Tricuspid AtresiaComplete obstruction to the tricuspid valve
• Tricuspid StenosisNarrowing of the tricuspid valve, resulting from a congenital defect of the valve leaflets or disease of the valve
• Tricuspid ValveThe valve at the junction of the right atrium with the right ventricle, which controls flow of blood into the ventricle before each contraction, and prevents backflow
• Tricuspid ValveThe structure that controls blood flow from the heart’s upper right chamber (the right atrium) into the lower right chamber (the right ventricle).
• Tricuspid Valve DiseaseTricuspid regurgitation is very common and usually due to heart failure. Stenosis of this valve is rare.
• Triggered Refers to an unpleasant and unexpected reminder of past pain or trauma. When we are triggered, we begin to feel emotions related to a trauma that happened to us in the past, even though those events aren’t being talked about directly.
• TriglycerideThe most common fatty substance found in the blood; normally stored as an energy source in fat tissue. High triglyceride levels often accompany other risk factors for heart disease, such as obesity.
• TroponinA Cardiac Enzyme used to diagnose a heart attack. Used now as early means of detection of myocardial damage and in preference to CK (Creatinine Kinase).
• Truncus ArteriosusA condition in which the aorta and main pulmonary artery are joined where they leave the heart. Blood from both ventricles passes across a VSD into this single arterial trunk.

• u

• UltrasoundHigh-frequency sound vibrations, which cannot be heard by the human ear, used in medical diagnosis.
• Unsaturated FatA type of ‘good’ fat found mainly in foods from plants and fish sources. They include monounsaturated fats and polyunsaturated fats.
• Unstable AnginaAt the lower end of the Acute Coronary Syndrome spectrum. Angina that is of new onset, more readily provoked and/or occurring at rest and without a rise in Troponin.
• Urinary CatheterThis is a tube that is passed into the bladder and allows the nurses to monitor how much urine is produced each hour.

• v

• ValveA structure in a blood vessel or the heart which ensures blood flows only one way. They are constructed of single or multiple flaps which swing open to allow blood to flow forwards and swing shut to prevent back flow. The valve flaps are referred to as 'leaflets' or 'cusps'.
• Valve RegurgitationAlso called valve insufficiency or incompetence. The one-way valve fails to close completely and leaks.
• Valve replacementAn operation to replace a heart valve that is either blocking normal blood flow or causing blood to leak backward into the heart (regurgitation).
• Valve StenosisThis can occur in any of the four heart valves and can be congenital or acquired. Most commonly the aortic valve is affected and due to age-related degeneration.
• ValvesThe “doors” between the chambers of the heart that allow blood to move forward and prevent it from moving backward. The heart valves are called tricuspid, pulmonary, mitral, and aortic and control the flow of blood into and out of the heart.
• Valvular Heart DiseaseWhen at least one of the four heart valves is diseased or damaged.
• ValvuloplastyReshaping of a heart valve with surgical or catheter techniques.
• Variants of Unknown SignificanceIn a small number of cases, genetic testing finds a “variant of unknown significance,” or VUS. This means there is a portion of the gene that looks different from the way it’s normally expected to look
• VUSIn a small number of cases, genetic testing finds a “variant of unknown significance,” or VUS. This means there is a portion of the gene that looks different from the way it’s normally expected to look
• Varicose veinAny vein that is abnormally dilated (widened).
• VascularPertains to the blood vessels.
• VasodilatorA medication that dilates a blood vessel through relaxation.
• VasodilatorsAny medicine that dilates (widens) the arteries.
• VasopressorsAny medicine that elevates blood pressure.
• Vasovagal SyncopeBlackout due to a sudden drop in blood pressure, with or without a decrease in heart rate, which is caused by a dysfunction of the nerves controlling the heart and blood vessels.
• Vegetative stateAfter a very severe brain injury, there may be a transition from coma into a vegetative state. Basic functions such as breathing and maintaining the heartbeat and blood pressure all continue, but without evidence of consciousness in any meaningful sense and with no response to the environment and no ability to communicate.
• VeinAny one of a series of blood vessels of the vascular system that carries blood from various parts of the body back to the heart, returning oxygen-poor blood to the heart.
• Vena CavaThe large veins (superior and inferior vena cava) that return all blood to the heart from the body.
• VentilateTo use a ventilator (respirator) to help a patient who cannot breath adequately for themselves.
• VentilatorA machine that delivers oxygen to a patient's lungs to assist with the breathing process. Also see 'Respirator'
• VAPPneumonia in a ventilated patient. Several aspects of ventilation leave patients vulnerable to infection. The breathing tube bypasses many of the body’s natural defences whilst immobility and the absence of coughing lead to retained secretions. A common complication of critical care therapy.
• Ventilator-associated pneumoniaPneumonia in a ventilated patient. Several aspects of ventilation leave patients vulnerable to infection. The breathing tube bypasses many of the body’s natural defences whilst immobility and the absence of coughing lead to retained secretions. A common complication of critical care therapy.
• VentricleOne of the two powerful muscular chambers at the bottom of the heart which pump blood out to the body with each heart contraction.
• VADA mechanical pump that helps the ventricles pump blood, easing the workload of the heart in patients with heart failure
• Ventricular Assist DeviceA mechanical pump that helps the ventricles pump blood, easing the workload of the heart in patients with heart failure
• Ventricular FibrillationVentricular fibrillation (VF) is a cause of cardiac arrest and sudden cardiac death. The ventricular muscle fibres contract randomly causing a complete failure of ventricular function. Most cases of ventricular fibrillation occur in patients with pre-existing known heart disease but the precise nature of the underlying cause of VF is not currently known
• VFVentricular fibrillation (VF) is a cause of cardiac arrest and sudden cardiac death. The ventricular muscle fibres contract randomly causing a complete failure of ventricular function. Most cases of ventricular fibrillation occur in patients with pre-existing known heart disease but the precise nature of the underlying cause of VF is not currently known
• Ventricular Septal DefectA defect (hole) in the ventricular septum which allows blood to shunt from one ventricle to the other.
• VSDA defect (hole) in the ventricular septum which allows blood to shunt from one ventricle to the other.
• Ventricular SeptumThe septum (partition or wall) between the two ventricles.
• Ventricular TachycardiaAn arrhythmia (abnormal heartbeat) in the ventricle characterized by a very fast heartbeat
• VTAn arrhythmia (abnormal heartbeat) in the ventricle characterized by a very fast heartbeat
• VertigoA feeling of dizziness or spinning.
• VestibularSystem in the middle of the ear which senses movement. Injury can lead to dizziness.

• w

• WeanedThis is a term used when a patient is being taken off of the breathing machine and is only undertaken when their condition is improving.
• Wellness Action Plan An easy, free and practical way of helping you to support your own mental health at work and, if you are a manager, helping you to support the mental health of your team members.
• Wernicke's AreaLocated in the temporal lobes, this is an area of the brain concerned with producing speech (See also BROCA'S AREA).
• White Matter White coloured nerve tissue in the brain is made up of myelin covered axons, which transmit electrical signals through the nervous system. The white matter lies underneath the grey matter of the cerebral cortex and white matter tracts travel down through the brainstem and into the spinal cord.
• Withdrawal of life-sustaining therapies Withdrawal of life-sustaining therapies refers to stopping or discontinuing medical treatments that keep a person alive but will not cure their underlying medical condition. This decision is often made when it is determined that further treatment is futile and the person is unlikely to recover or when the person is suffering and the continuation of treatment is causing more harm than good. Examples of life-sustaining therapies include mechanical ventilation for people who can no longer(...)
• WSLT Withdrawal of life-sustaining therapies refers to stopping or discontinuing medical treatments that keep a person alive but will not cure their underlying medical condition. This decision is often made when it is determined that further treatment is futile and the person is unlikely to recover or when the person is suffering and the continuation of treatment is causing more harm than good. Examples of life-sustaining therapies include mechanical ventilation for people who can no longer(...)
• Wolff-Parkinson-White syndromeA condition in which an extra electrical pathway connects the atria (two upper chambers) and the ventricles (two lower chambers). It may cause a rapid heartbeat.

• x

• X-rayForm of radiation used to create a picture of internal body structures on film.

• y

• Y WaveThe wave in the atrial and venous pulse curves reflecting rapid filling of the ventricles just after the atrioventricular valves open.

• z

• ZyxinA protein found in fibroblasts, smooth muscle and pigmented retinal epithelium.