Interpreting the Coronary Artery Calcium Score - Critical Information for the Practicing Physician.

Coronary artery calcium (CAC) scanning is a routine test for assessing the severity of atherosclerosis in asymptomatic individuals. This inexpensive, non-invasive test quantifies the calcium deposition in the four principal coronary arteries. Correct interpretation is important to the physician (for recommending therapy) and to the patient (for determining his/her lifetime risk of a cardiovascular event). A score of zero indicates that a cardiovascular event is extremely unlikely in the next five years. In contrast, a score greater than zero portends a coronary event. The higher the score, the greater the risk. Both the arterial location of the calcium and the number of coronary arteries involved alter the interpretation of the calcium score. At any given age, females have significantly lower scores than males. One-third of individuals with scores greater than 1,000 will have a cardiovascular event within three years. For all elevated calcium scores, aggressive treatment is warranted, including significant lifestyle changes and medications to reduce LDL-cholesterol. Understanding the importance of the coronary artery calcium score will result in improved therapy and patient compliance.