Prayers sent. My son is not much younger....
Heavy exercise (bike riding and mountain climbing) causing dehydration, followed by an 8 hour sitting session in an office chair, followed by three beers (causing more dehydration) then bed.
Stagnation + dehydration = blood clots = heart attack
To top it off, athletes have a lower-than-average resting heart rate, that can cut back on circulation and increase the risk.
(I’m just passing on information because I’m angry that NOBODY ever told me that these were risk factors)