Anomalous origin of the coronary artery arising from the opposite sinus: prevalence and outcomes in patients undergoing coronary CTA.

Aims: The impact of coronary computed tomographic angiography (CTA) on management of anomalous origin of the coronary artery arising from the opposite sinus (ACAOS) remains uncertain. We examined the prevalence, anatomical characterization, and outcomes of ACAOS patients undergoing CTA.

Methods And Results: Among 5991 patients referred for CTA at two tertiary hospitals between January 2004 and June 2014, we identified 103 patients (1.7% prevalence) with 110 ACAOS vessels. Mean age was 52 years (range 5-83, 63% male), with 55% previously known ACAOS and 45% discovered on CTA. ACAOS subtypes included: 39% interarterial (n = 40 anomalous right coronary artery, n = 3 anomalous left coronary artery), 38% retroaortic, 15% subpulmonic, 5% prepulmonic, and 2% other. ACAOS patients were assessed for symptoms, ischaemic test results, revascularization, all-cause or cardiovascular (CV) death, and myocardial infarction. CTAs were reviewed for ACAOS course, take-off height and angle, length and severity of proximal narrowing, intramural course, and obstructive coronary artery disease (CAD). In follow-up (median 5.8 years), there were 20 surgical revascularizations and 3 CV deaths. After adjusting for obstructive CAD (n = 21/103, 20%), variables associated with ACAOS revascularization included the following: CV symptoms, proximal vessel narrowing ≥50%, length of narrowing >5.4 mm, and an interarterial course.

Conclusion: The prevalence of ACAOS on CTA was 1.7%, including 45% of cases discovered incidentally. CTA provided excellent characterization of ACAOS features associated with coronary revascularization, including the length and severity of proximal vessel narrowing.