Surgical outcomes of complete AVSD repair using a modified two-patch technique

Background: Residual left atrioventricular valve (LAVV) regurgitation and left ventricular outflow tract (LVOT) obstruction remain the main challenges after complete atrioventricular septal defect (AVSD) repair. We evaluated early and midterm outcomes of a modified two-patch technique with LAVV leaflet augmentation. Methods: Retrospective single-center series of 69 patients (2015–2024). Survival and freedom from reoperation were estimated by Kaplan–Meier analysis; LAVV regurgitation was compared in paired early and 1-year echocardiograms, and predictors of moderate-to-severe residual regurgitation were assessed by logistic regression. Results: Median age was 7.2 months (59.4% older than 6 months); 47.8% had Down syndrome and 69.6% had moderate-to-severe preoperative LAVV regurgitation. Mortality was 3/69 (4.3%; early 1.4%); survival was 96.9% at 1 year and 94.7% at 3–5 years. LVOT obstruction occurred in one patient (1.4%), and freedom from cardiac reoperation was 91.7%. Severe early LAVV regurgitation (21.7%) was unchanged at 1 year in 50 paired patients (22.0% vs. 22.0%; p = 1.0); it was more frequent with severe preoperative regurgitation (53.3% vs. 13.0%; p = 0.002) and without Down syndrome (33.3% vs. 9.1%; p = 0.020), but was not related to age or pulmonary artery pressure. Both late deaths were related to AV valve regurgitation and heart failure. Moderate-to-severe preoperative regurgitation independently predicted residual regurgitation (OR 3.95; 95% CI 1.31–11.93). Conclusions: The technique achieved low mortality and rare LVOT obstruction. Residual LAVV regurgitation, driven mainly by preoperative valve status, remains the main problem, supporting repair at 3–6 months of age and close surveillance of patients with significant regurgitation.