Abstract
This single-center study investigated long-term outcomes after surgical correction of atrioventricular septal defect (AVSD).A total of 248 patients underwent biventricular repair for AVSD between 1995 and 2022. A total of 208 (83.9%) patients had complete (cAVSD), 29 (11.7%) partial (pAVSD), and 11 (4.4%) transitional AVSD (tAVSD). Associated cardiovascular anomalies were present in 88 (35.5%) cases and 61 (24.6%) patients were born prematurely. Median age at repair was 7.1 for cAVSD, 23.7 for pAVSD, and 13 months for tAVSD.Overall survival or reoperation incidence did not differ significantly between AVSD types and improved significantly over surgical eras. Survival of the entire cohort was 88.3% at 10, 83.8% at 15, and 79.6% at 25 years. Prematurity (hazard ratio [HR]: 2.43, p = 0.029), low weight (<4 kg) (HR: 3.05, p = 0.028), and partial cleft closure (HR: 2.43, p = 0.037) were independent risk factors for mortality. Forty-eight patients (19.4%) underwent a total of 64 reoperations over the study period. The main indication for reoperation was left atrioventricular valve regurgitation (LAVVR) with 55/64 procedures. However, 36% of procedures were performed to address several lesions, with left ventricular outflow tract obstruction being the second most common indication. Freedom from reoperation was 78.2, 75.8, and 72.5% at 10, 15, and 25 years, respectively. The incidence of reoperation increased significantly in association with early postoperative LAVVR ≥ I-II° (HR: 2.6, 95% confidence interval [CI]: 1.4-4.7, p = 0.002) and presence of residual cardiac defects (HR: 2.0, 95% CI: 1.1-3.6, p = 0.018).While LAVVR is the main indication for reoperation, a significant proportion of procedures address additional pathologies. Premature patients and those with associated cardiovascular anomalies should receive special attention during postoperative follow-up.