If you have an ICD or pacemaker implanted there is often a period after where the incision area can be tender. If so, you may want a little extra protection for it when travelling in a car as the seat belt may rub or apply irritating pressure.
A small cushion or rolled up cloth may help but if you need something a little more substantial or sturdy you may want to consider getting a purpose built protector.
For those who play sports or have the potential to receive an impact in the ICD region during their daily lives may consider getting one of the protectors available.
They also do S-ICD protection
Padded Hockey Shirts
Seat Belt Protectors
Pressure Products (US) for Seatbelt and Bra protection products