Detection of Subclinical Cardiovascular Disease: The Emerging Role of Electron Beam Computed Tomography

Background. Although extraordinary advances have been made in the management of advanced coronary artery disease, little progress has been made in its prevention. Traditional screening methods utilizing risk factor profiles and exercise treadmill tests have failed to identify populations who will subsequently have coronary events with a high degree of predictive accuracy. Methods. We review the pathobiologic basis and clinical utility of electron beam computed tomography (EBCT) to detect coronary artery calcium as a screening tool for subclinical coronary artery disease. Because EBCT is able to perform subsecond imaging of the heart, it can detect and quantitate coronary artery calcium with a high degree of precision. Coronary artery calcium is a marker of complex atherosclerosis. Results. Over 4,000 asymptomatic patients in several series have been studied with EBCT and followed prospectively for an average of 42 months (range 37–72 months). A positive scan is associated with a risk ratio for future coronary events of 8.7 (95% confidence interval 2.67 to 28.13). These data indicate that EBCT has the ability to detect subclinical coronary artery disease and predict future coronary events better than any previous existing method or technology. Conclusion. EBCT coronary artery screening may prove to be a valuable adjunct to the traditional methods for the detection of subclinical coronary artery disease and to identify those who would benefit from focused preventive therapies.