Coronary calcium
The performance of low-radiation, non-contrast cardiac computed tomography to detect and quantify coronary artery calcium (CAC) is a well-studied, highly reproducible technique shown to significantly improve individual atherosclerotic cardiovascular disease risk prediction as compared to risk factor-based approaches. Using outcomes-based net reclassification, CAC testing has been shown to accurately reclassify 35–65% of patients estimated to be at intermediate and high risk according to standard risk scores. This improvement in prognostic accuracy may result in more precise and appropriate utilization of statins and aspirin for primary cardiovascular disease prevention, without a significant increase in overall costs. Accordingly, current European Society of Cardiology and other international guidelines and appropriateness criteria incorporate CAC testing for clinical use primarily among patients at intermediate risk for fatal cardiovascular disease by standard risk scores, and when the decision to use lifelong preventative medications remains unclear.