CS, I agree with the above poster, as I have an ICD implanted, which also has a built in pacemaker. I'm only 46, but I've had two heart attacks. Anyway, one of the first things I asked my doctor, since if I "drop dead" from sudden cardiac death, the defibrillator will go off, and restart my heart. But I asked him, ok, so what happens when I'm 85 or 90, and it is "my time to go", but the damn ICD will keep kicking in.