I have a coronary calcium issue just like you. My original heatscan six years ago was at 113. Three years later it was 178 even though I had been taking Zocor during that time. I have been thinking of going for another scan, but I am not sure I could handle the result. It could be really high by now.
After my jump from 113 to 178, I went to a heartscan cardiologist and he mentioned that existing non-calcified deposits may calcify during statin treatment. This can cause an increase in calcium score even though you have arrested the deposit of materials in the artery. Only calcified deposits show up on the scan.
Like you, I have controlled my cholesterol very well. I have NEVER had a TC over 200. My HDL has always been very high for a male (sometimes as high as 80) and yet I have considerable calcification.
I wish I had an answer for you my friend. All I can say is you are not alone. A good friend of mine (also a skinny runner with normal cholesterol) had a 500
score last year.
I assume you are not a smoker or diabetic? I was a heavy smoker until I was 29. I am 55 now. I am hoping that is the cause of my calcification....and it's not progressing because I quit.
Have your dr check your Lp(a) and homocysteine too...my Lp(a) was high. High dose niacin can bring it down to normal levels. I would guess your cardio has looked into these issues. If not, push it.
I am not convinced cholesterol is the smoking gun for many people with heart disease. Keep up the good lifestyle and you're doing all you can do. Don't let your calcium score cause you excessive worry. At least you know there may be a problem and you are dealing with it to the best of your ability.
Running_guy