Coronary artery calcium (CAC) screening is a test in which a computed tomography (CT) scan is used to detect calcium-containing plaques in the coronary arteries. A score of 0 means there is no detectable calcium—and you have a low risk of having a heart attack in the next 10 years.
A CAC score can be informative when there’s uncertainty about starting statin treatment— if, for example, someone is at intermediate risk of having a first-time heart attack or stroke in the next decade.
Growing evidence finds that a CAC score can even be helpful in some cases where a statin would routinely be recommended. A study published in the European Journal of Preventive Cardiology in November 2018 focused on 5,600 middle-aged and older Americans who were free of heart disease and had their risk factors assessed. They also underwent CAC screening.
Close to 1,700 study participants would have had statin treatment recommended based on their estimated risk of dying from cardiovascular disease over the next 10 years. However, nearly one-third of those people had a CAC of 0. Over 10 years, less than 3 percent of that group ended up dying of heart disease or stroke—versus roughly 9 percent of those with higher CAC scores.
The findings offer further evidence that CAC screening can help pinpoint who will most benefit from statins—and who may not need the drugs. To find out if the test is worthwhile for you, talk with your doctor about your heart disease risk factors.