Recent studies demonstrate some effectiveness in assessing coronary artery calcification (CAC) to determine risk for coronary heart disease, but more studies are needed to evaluate the metric, an editorial comment published in the October edition of the Journal of the American College of Cardiology cautioned.
“There are still several questions to be answered before the practical implication of the CAC score can be taken into consideration in daily clinical practice,” argued the editorial’s author, Daniel A. Duprez, MD, PhD, of the medical school of the University of Minnesota in Minneapolis. “With the introduction of new diagnostic markers, there should be an evaluation of the following criteria: 1) the proof of concept; 2) the prospective validation; 3) the incremental diagnostic value; 4) the clinical utility; 5) the clinical outcomes; and 6) the cost-effectiveness.”
Duprez discussed several recent studies, two of which were published in JACC, which had found statistically significant associations between CAC scores and incidence of major cardiac events or coronary heart disease (CHD). Two studies, the Heinz Nixdorf Recall and Rotterdam studies, used CAC scores in covariation with other risk indicators to differentiate patient groups at higher or lower risks for CHD, finding several statistically significant relationships.
Duprez pointed out that several studies have left doubts as to the predictability of CHD using CAC, such as the CORE64 study, in which CAC scores were unable to reliably predict obstructive stenosis or the need for revascularization in a sample.
Duprez concluded by cautiously affirming that “noninvasive assessment of atherosclerosis using CAC score is regarded as most useful in asymptomatic subjects classified in intermediate Framingham risk range in which treatment decisions are often uncertain.”