BackgroundClosure of a secundum atrial septal defect (ASD) is possible through surgical intervention or device placement. During surgical intervention, concomitant pathologies are corrected. The present study was conducted to investigate the outcomes of surgical ASD closure, to determine the risk factors of mortality, and establish the effects of concomitant disease correction.MethodsBetween October 1989 and October 2009, 693 adults underwent surgery for secundum ASD. Their mean age was 40.9±13.1 years, and 199 (28.7%) were male. Preoperatively, atrial fibrillation was noted in 39 patients (5.6%) and significant tricuspid regurgitation (TR) in 137 patients (19.8%). The mean follow-up duration was 12.4±4.7 years.ResultsThere was no 30-day mortality. The 1-, 5-, 10-, and 20-year survival rates were 99.4%, 96.8%, 94.5%, and 81.6%, respectively. In multivariate analysis, significant preoperative TR (hazard ratio [HR], 1.95; 95% confidence interval [CI], 1.09 to 3.16; p=0.023) and preoperative age (HR, 1.04; 95% CI, 1.01 to 1.06; p=0.001) were independent risk factors for late mortality. The TR grade significantly decreased after ASD closure with tricuspid repair. However, in patients with more than mild TR, repair was not associated with improved long-term survival (p=0.518).ConclusionSurgical ASD closure is safe. Significant preoperative TR and age showed a strong negative correlation with survival. Our data showed that tricuspid valve repair improved the TR grade effectively. However, no effect on long-term survival was found. Therefore, early surgery before the development of significant TR mat be beneficial for improving postoperative survival.