Fate of Neoaortic Valve in Patients undergoing Arterial Switch Operation for Transposition of Great Arteries

Objectives: The aim of this study was to evaluate the incidence of neo-aortic regurgitation (AR) after arterial switch operation (ASO) and the associated risk factors. Methods: Retrospective review of records of 289 patients undergoing arterial switch operation from 2005 to 2015 was performed along with echocardiographic examination of neo-aortic valve, ventricular function and associated risk factors. Results: Mean weight at operation was 3.5 ± 0.25 kg. 150 patients had associated ventricular septal defect (VSD) out of which 19 were Taussig-Bing type and remaining 139 patients had intact ventricular septum. At last follow up (4.82 ± 3.1; Range 1-11 years), 35 patients (12.1 %) had developed AR; 24 had trivial AR and 10 had mild AR while only 1 had moderate AR. Freedom from intervention for aortic valve after ASO was 100% after 10 years. On univariate logistic regression analysis, complex transposition of great arteries (TGA) (presence of VSD, associated abnormalities like TAPVC, arch anomalies) was found to be a risk factor for AR. Presence of left ventricular outflow tract obstruction (LVOTO), pre-operative Aortapulmonary artery size discrepancy and abnormal coronary artery anatomy were also significant risk factors for neo-aortic regurgitation. On multi-variate logistic regression analysis, presence of VSD, LVOTO, abnormal coronary artery anatomy and Aorta – pulmonary artery size discrepancy were significantly associated risk factors for neo-aortic regurgitation. Conclusions: In our experience, incidence of AR after ASO remains low. Development of AR is related to presence of complex TGA, pre-operative aorta pulmonary size discrepancy and abnormal coronary artery anatomy. Keywords: Transposition of great arteries; Arterial switch operation; Aortic regurgitatio