Calcium Score

 I get a lot of requests from patients asking to do a “calcium score”.  A calcium score (CAC - coronary artery calcium) is an assessment of calcium deposition in coronary arteries, as determined through a CT scan of the heart. Since calcium deposits in areas of inflammation, and since plaques, the cholesterol accumulation in arteries often involves inflammation, the degree of calcium can be used as a surrogate marker for the degree of coronary artery disease one may have. 

The problem with CAC scores is what do with the information obtained. Many patients ask for them as part of an assessment for chest pain. Indeed, many cardiologists will obtain a CAC score, along with a stress test and an echocardiogram, as part of a “cardiovascular evaluation.”   

We can predict fairly well the likelihood of developing clinically significant coronary artery disease (CAD) by calculating something called the ASCVD Risk Score. By clinically significant, I mean CAD that is gong to result in angina or a heart attack.  By looking at cholesterol levels. gender, age, smoking status, history of diabetes and hypertension, we can estimate people being of low, intermediate or high risk of developing clinically significant coronary artery disease.   In addressing this, there are some variable - age and gender - the we cannot alter.  We can encourage individuals to stop smoking and certainly diabetes and hypertension can be managed.  For those in the lower risk group, we do not necessarily need to treat the cholesterol with statins, or other medications; of those in the high risk group, treating definitely confers a survival benefit.   The issue is what to do with the intermediate risk group.  While it would not be wrong to use medications in this group, sometimes we want to be more nuanced, and this is where the CAC score comes in.

A high CAC score would sway one to treat with medication, and a score of zero could sway one not to.  But, again, this is only useful in the intermediate group.  If one's risk is already established as high, by virtue of the ASCVD Risk Score, the CAC score adds no useful information.  Those patients should be offered treatment with a cholesterol medication, regardless of the CAC score.  

So, the ONLY utility of getting the CAC score is to make a management decision in those of intermediate risk as established by the ASCVD Risk Score. 




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