There's more to cardiac health than having a heart attack. My long term buddy has led a sedentary life for as long as I've known him... which is a long time. While my family has a history of heart issues (hypertensive here, and a brother who had two heard attacks by age 54 as well as a quadruple bypass, in spite of "looking" fit) my buddy's family does not. However, he is obese, and eats poorly.
Recently, he suffered a severe immersion pulmonary edema. A lesser diver may well have died, but he completed required deco (18 mins) and with the help of others on the boat, he was hauled out, and recovered successfully. We all learned after the fact that this was in fact the third time this had happened, although this was by far, the most serious episode.
To make a long story short, this led to a battery of tests including stress tests, an echo-cardiogram and even an angiogram (all for the price of parking Wookie, 'cause we are civilized up here in Canada). His diagnosis was a "weak" heart and he was told to lose 75 pounds and get exercising... Which I know he won't do. At my urging, he consulted with a respected diving Physician (who is also a friend) who basically told him it was time to stop diving. My buddy "negotiated" an approval to "sport dive"... 130', no deco. Whether this is wise or not, time will tell... He's 58, and loves diving as much as I do, so whether he's going to follow this advice is hard to say.
This situation has created a little "stress" in our group of diving friends. This guy is a long time friend and we don't want him to drop dead. Even more so, we don't want him to drop dead while we're diving with him. Apart from the paperwork involved, this would be unpleasant for all concerned.
One of my other friends talked to him last fall about dropping out of their Gunilda trip (260') and he opted to sit out of a high current dive with me in December, but the season is just getting going here now, so who knows what's going to happen.
We are all hoping that as much as well will miss diving with him, that he takes his Doc's advice and stops diving.
I don't profess to be be super fit, but I am not overweight, I exercise regularly (although at a much lower intensity than I did years ago) and so on, but the reality is that for those of us that are "getting on", we are at increased risk from all sorts of things including heart issues.
In Tobermory, we have lost three divers to health issues while they were diving over the past few years. One of them, just last summer, appeared to be in great health (given he was 70 or so) but none the less, he expired mid-dive, while on his deco stop. We heard the whole thing unfold on the VHF and it was very unpleasant for those directly involved. He was a good friend to many of my friends, and an acquaintance of mine.
So get off of your asses folks, and get in shape. If you aren't going to do it, then hang up your fins and take up bridge...