As I put on my old paramedic hat for a moment:
There is a bit of a scam going on in terms of heart attack survival rates and CPR. You need to ask how 'survival rate' is calculated. In most places, that is defined as the patient reaches the ER alive. Compare this to the much smaller percentage of patients who walk out of the hospital neurologically intact.
Certainly CPR is a good thing, and if I had a witnessed collapse on the street with no pulse, I would want bystanders to perform CPR. But it is not a miracle intervention and people should not feel bad if the patient still does not make it.