Is There a Role of Coronary CTA in Primary Prevention? Current State and Future Directions

Purpose of Review: Information on subclinical atherosclerosis burden provides prognostic information on atherosclerotic cardiovascular disease (ASCVD) risk beyond what can be achieved by traditional risk factors alone and may therefore improve allocation of preventive treatment in primary prevention. The purpose of this review is to discuss the potential role and value of assessing subclinical atherosclerosis using coronary artery calcium (CAC) versus computed tomography angiography (CTA) among asymptomatic patients in the context of current primary prevention cholesterol guidelines. Recent Findings: Since 2013, primary prevention cholesterol guidelines have lowered the treatment threshold for initiating statin therapy resulting in high statin eligibility and sensitivity for detecting ASCVD events. Thus, one of the main advantages of assessing subclinical atherosclerosis is to identify those individuals who are at so low ASCVD risk that preventive treatment may safely be withhold. Numerous studies have shown that both CAC and CTA provide highly valuable information on ASCVD risk in the individual patient. However, while extensive data exist regarding the ability of CAC to improve treatment allocation in the context of primary prevention guidelines, such data is sparse for CTA. Furthermore, there is no data to show that CTA improves risk classification and treatment allocation in primary prevention beyond what can be achieved by assessment of CAC. Summary: Although CTA provides important information regarding prognosis in symptomatic patients undergoing clinical CTA, there is no strong evidence to support its use in the primary prevention setting. Thus, the potential value of CTA in primary prevention is not clear and is currently not recommended by guidelines.