Congenital Coronary Anomalies Detected by Coronary Computed Tomography Compared to Invasive Coronary Angiography

Background: As coronary computed tomography angiography (CCTA) has emerged as a non-invasive alternative for evaluation of coronary anatomy with a lower referral threshold than invasive coronary angiography (ICA), the prevalence of coronary anomalies in CCTA may more closely reflect the true prevalence in the general population. Morphological features of coronary anomalies can be evaluated more precisely by CCTA than by ICA, which might lead to a higher identification of congenital coronary anomalies in CCTA compared to ICA.To evaluate the incidence, clinical and morphological features of the anatomy of patients with coronary anomalies detected either by coronary computed tomography angiography (CCTA) with prospective ECG-triggering or invasive coronary angiography (ICA).

Methods: Consecutive patients underwent 64-slice CCTA (n = 1'759) with prospective ECG-triggering or ICA (n = 9'782) and coronary anatomy was evaluated for identification of coronary anomalies to predefined criteria (origin, course and termination) according to international recommendations.

Results: The prevalence of coronary anomalies was 7.9% (n = 138) in CCTA and 2.1% in ICA (n = 203; p < 0.01). The most commonly coronary anomaly detected by CCTA was myocardial bridging 42.8% (n = 59) vs. 21.2% (n = 43); p < 0.01, while with ICA an absent left main trunk was the most observed anomaly 36.0% (n = 73; p < 0.01). In 9.4% (n = 13) of identified coronary anomalies in CCTA 9.4% were potentially serious coronary anaomalies, defined as a course of the coronary artery between aorta and pulmonary artery were identified.

Conclusion: The prevalence of coronary anomalies is substantially higher with CCTA than ICA even after exclusion of patients with myocardial bridging which is more frequently found with CCTA. This suggests that the true prevalence of coronary anomalies in the general population may have been underestimated based on ICA.