Multiple ways exist to induce a heart attack that do NOT leave anything detectable unless special tests are used. Two I know of just plain are NOT detectable.
So this really doesn’t mean anything.
BTW, sometimes 79 year old people do just have a heart attack and die. In fact, I had a non-drinking non-smoking workout beast friend drop dead of a heart attack at 41. Dead before he hit the ground. Sometimes is just happens.
it*