Anomalous interarterial left coronary artery: An evidence based systematic overview

Background: Isolated anomalous left main coronary artery (ALMCA) from the right aortic sinus of Valsalva (RASV) with an interarterial course between the pulmonary trunk and aorta is a rare congenital abnormality. We performed an evidence based systematic overview spanning 4 decades to assess the prevalence, clinical features and management of this anomaly. Methods: A computerized search spanning 40 years was conducted to identify articles describing cases of ALMCA arising from the RASV with an interarterial course. The bibliographies of all relevant articles were also searched. Results: The search identified 264 cases. Age ranged from 3.5 months to 87 years. Male/female ratio was 2.9/1. Forty-nine percent of the cases were diagnosed postmortem. Cardiac catheterization was the most common diagnostic tool (41.7%) followed by echocardiography, magnetic resonance imaging (MRI) and computerized assisted tomography. Fifty-seven (21.6%) cases underwent surgical procedures with no mortality and low morbidity. Conclusions: ALMCA from the RASV is associated with increased risk of sudden death, notably in young patients. Unfortunately the majority are diagnosed postmortem. More than a third present with sudden cardiac death. Echocardiography, computerized assisted tomography and cardiac MRI are valuable non-invasive diagnostic tools. Cardiac catheterization provides a definitive diagnosis in the majority. Surgical correction is the mainstay of treatment with low risk and good anatomic and functional results.