Role of CT Coronary Calcium Scanning and Angiography in Evaluation of Cardiovascular Risk

Coronary artery calcium identified by means of computed tomography is a highly reliable method for identification of coronary atherosclerosis. The Agatston method is the most common coronary calcium scoring method used. Coronary artery calcium is independently associated with future risk of coronary artery disease and all-cause mortality. The coronary artery calcium score improves risk prediction for a future cardiovascular event and mortality beyond traditional risk assessment methods such as the Framingham risk score and can therefore assist in the decision-making processing of identifying patients that would benefit from preventive pharmacotherapy like statins. Current guidelines recommend its use in intermediate-risk asymptomatic individuals where it appears to be the most predictive of future risk. The absence of coronary artery calcium is associated with a very low risk of cardiovascular death and myocardial ischemia over the next 5 years. Coronary computed tomography angiography provides comprehensive information regarding the location, severity, and characteristics of atherosclerotic plaque. Coronary computed tomography angiography has been shown to be more reliable that other noninvasive functional stress testing modalities in the evaluation for ischemia. The negative predictive value of coronary computed tomography angiography in ruling out obstructive coronary artery disease is 99% which makes it a reliable technique in the emergency department for ruling out obstructive coronary artery disease and acute coronary syndrome in patients with low to intermediate risk with acute chest pain.