Optimum Cholesterol

Could stress alone cause a heart attack?
Let's say someone is extremely healthy. They are optimum weight, blood pressure and cholesterol. They exercise often, usually running, and their family has a small history of heart disease (one person not in immediate family had heart attack young, but they had other problems as well). If they are under stress sometimes, you know like a little more than the average person, but they do breathing exercises and stuff like that to try to help manage it, are they at risk for a heart attack. I would appreciate it if somebody with actual knowledge answered, not just a random person, no offense. By the way, yes it is me and I'm 16 (young I know, but for future reference. I'm never going to stop running unless I have to because I love it.
I am also asking this, by the way, because occasionally I get chest pains, but I already got it checked and it's fine, so I'm not worried about that at all.
Sadly, yes it is possible, but fortunately it's rare.
It's rare because heart attacks aren't caused by so-called "hypertension" but are caused by random, un-anticipated transient very high stress peaks, which can occur (for instance) by sudden shock, excessive physical exercise, or emotion, (orgasm is an excellent example), while the heart is already at a very high cardiac load-level.
It's possible because sometimes there is an underlying defect -with the heart, or the nervous mechanisms controlling the way the heart responds to stress. In cases like these, the sudden high transients are enough to overcome a weakened system and it is often genetically linked, as an aberration.
I'm sure you're fine, but do appreciate that the medical profession's way of measuring your B/P and performance 'at rest' is akin to assessing a racing car's performance while idling. It tells nothing about what it's like when racing.!
For what it's worth, my honest opinion is that one annual 'dynamic' test, following a Bruce protocol, is worth 100 potty static or "at rest" tests in the doctor's surgery !
EDIT: Regarding the "short answer is NO" below, while coronary blockage caused by dislodged plaque, this is only one of several possible causes of heart attack... to say "no" is simply incorrect..