Yes, "killer' is a very confusing word in modern slang. What are your numbers for total, HDL, and LDL? High coronary calcium in long-time very fit endurance athletes is usually not a concern. It's composed of hard calcium which apparently does not break up and cause heart attacks. Question is, do you fit that definition? Many docs overprescribe statins in such cases. How's your blood pressure and morning resting and standing HRs? I'd certainly recommend going with the stress test. When I was 72 and had a high calcium score, I tested as a fit 47 y.o. That felt good.
The cardio prescribed a statin anyway, which put me in a total tailspin. They are not for everyone. My power immediately went way down due to severe muscle pain and a couple months later I developed polymyalgia rheumatica (PMR). Whether the statin had anything to do with that is an open question. That said, I wish I could take a statin and be fine with it. Statistically it's safer. My cycling doc says in my case, I'm safer riding lots than taking a statin and not doing so. So there's that.
All my cholesterol numbers are in the good range. The cardio prescribed on the basis of my age and calcium score, which would have been correct in the case of a "normal" person.
I take a baby aspirin. I'm placing a bet that I'm less likely to have a concussion than I am to have a coronary blood clot. I don't tree ski in the backcountry anymore.
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Results matter