Prevalence and anatomical variants of anomalous aortic origin of a coronary artery (AAOCA) assessed by coronary CT angiography: a single-center study

Abstract Background Anomalous aortic origin of a coronary artery (AAOCA) is a congenital coronary anomaly in which coronary arteries arise from inappropriate aortic sinuses and may follow abnormal courses. Coronary computed tomography angiography (CCTA) is the imaging modality of choice for accurate anatomical assessment of these variants. Purpose To assess the prevalence, anatomical types, and courses of AAOCA identified by CCTA in a large, single-center population. Methods From 16,680 consecutive CCTA scans performed for clinical indications, 102 patients were identified with AAOCA, corresponding to a prevalence of 0.61%. Anomalies were categorized based on origin and course, following established classification systems. Results The most frequent anomaly was the circumflex artery (Cx) arising from the right coronary sinus, observed in 33 patients (32.4%), followed by Cx arising from the right coronary artery (RCA) in 13 cases (12.7%). RCA arising from the left anterior sinus with an interarterial course was found in 15 patients (14.7%), and left main coronary artery (LMCA) arising from the right sinus was present in 6 patients (5.9%). Additionally, the left anterior descending artery (LAD) arising from the RCA was identified in 7 cases (6.9%). LMCA originating from the RCA was observed in 2 cases (2.0%). In terms of anatomical course, retroaortic trajectory was the most common, present in 48 patients (47.1%), followed by interarterial course between the aorta and pulmonary artery in 29 patients (28.4%). Other types of courses were identified in 19 cases (18.6%), while prepulmonic and retrocardiac courses were found in 2 cases each (2.0%). No subpulmonic courses were observed. Conclusions AAOCA was identified in 0.61% of patients undergoing CCTA, with the most prevalent variants involving the Cx artery arising from an aberrant origin. Retroaortic and interarterial were the most frequent anatomical courses. These findings underscore the utility of CCTA in the detection and characterization of coronary artery anomalies and highlight the importance of recognizing patterns with potential clinical significance.