Predictors of reoperation and mortality after complete atrioventricular septal defect repair

Objectives: Previous studies investigating risk factors associated with reoperation or mortality after repair of complete atrioventricular septal defect (CAVSD) often have not included sizeable cohorts undergoing modified single-patch repair. Both double patch and modified single-patch techniques have been widely used in Australia since the 1990s. Using a large multi-institutional cohort, we aimed to identify risk factors associated with reoperation or mortality following CAVSD repair.

Methods: Between January 1990 and December 2015, a total of 829 patients underwent biventricular surgical repair of CAVSD in Australia at 4 centres. Patients with associated tetralogy of Fallot and other conotruncal abnormalities were excluded. Demographic details, postoperative outcomes including reoperation and survival, and associated risk factors were analysed.

Results: Fifty-six patients (6.8%) required early reoperation (≤30 days) for significant left atrioventricular valve regurgitation or residual septal defects. Freedom from reoperation at 10, 15 and 20 years was 82.7%, 81.1% and 77%, respectively. Patients without Down syndrome and moderate left atrioventricular valve regurgitation on postoperative echocardiogram were found to be independent risk factors for reoperation. Operative mortality was 3.3%. Overall survival at 10, 15 and 20 years was 91.7%, 90.7% and 88.7%, respectively. Prior pulmonary artery banding was a predictor for mortality, while later surgical era (2010-2015) was associated with a reduction in mortality risk.

Conclusions: Improved survival in the contemporary era is in keeping with improvements in surgical management and higher rates of primary CAVSD repair over time. The presence of residual moderate left atrioventricular valve regurgitation on postoperative echocardiography is an important factor associated with reoperation and close surveillance is essential to allow timely reintervention. Primary CAVSD repair at age <3 months should be preferenced to palliation with pulmonary artery banding due to the association of pulmonary artery banding with mortality in the long-term.