Coronary-calcium screening to improve risk stratification in primary prevention

Coronary artery disease is very prevalent in the United States where over 7 million people suffer from it, and more than 500,000 die from its complications annually. For the majority of individuals suffering an acute myocardial infarction, the event represents the first indication of the presence of underlying coronary atherosclerosis. Furthermore, due to the outward remodeling of arteries that slowly accumulate atheroma in their imtima (Glagov effect), sudden death or acute myocardial infarction may occur in the absence of obstructive luminal atherosclerotic plaque. Therefore, it might seem highly desirable to detect atherosclerosis in its early stages to implement effective preventive measures rather than apply delayed treatment. Yet, statistics from primary care and sub-specialty practices indicate that the preventive attitude of the majority of physicians is not sufficiently developed, and most training programs still struggle to implement strong educational curricula in this field. To these limitations, one may add that traditional risk factors help predict only about 60% to 65% of the risk, while many individuals continue to suffer events in the absence of established risk factors for atherosclerosis. In light of this knowledge, several tools have been developed to identify atherosclerotic disease in its pre-clinical stages in the hope of modifying its natural history. This review deals with the utilization of electron beam tomography for detection of coronary arterial calcium as an additional tool to risk stratify asymptomatic individuals.