Good that your son at least knows that he has a problem. Up here in Oregon, we just recently had a couple of young high school athletes who dropped dead. They had no known heart defect. One was able to be defibrillated, but he’s got a long road before he recovers completely, if ever. The other boy unfortunately did not survive.
My son with only 2 coronary arteries played foot ball all through school and as a junior was playing varsity...ran track and the 4 man relay from his high school (he and 3 of his buddies) went on to state meet, didn’t win there. Never showed anything up until his 40’s....He had no other heart problems tho at that time and we didn’t know about his arteries until he had a test done with the dye (forget what its called, senior moment, I am sorry) and it showed up. I was grateful when my 2 oldest ones passed their fathers age when he died...he also had no cardiac history, just died in the back yard sitting beside his truck while we were putting up hay..he left the barn because of the dust from the hay coming off the elevator and the rest of us finished and found him. He didn’t say he had chest pain, the idiot, we would have stopped and taken him to emergency...
I nagged my kids from that time on to watch out for their health, they were all married except one....