The effect of body weight in infants undergoing ventricular septal defect closure: A report from the Nationwide Japanese Congenital Surgical Database

Objective: In infants with ventricular septal defect (VSD) who undergo surgical intervention, body weight, along with age, is frequently thought to be the decisive predictor of morbidity and mortality after surgery; however, its information on quantitative risk assessment is limited. Methods: All infants (<1 year old) with a fundamental diagnosis of VSD who underwent surgical VSD closure or pulmonary artery banding between 2012 and 2016 were identified from the Japan Cardiovascular Surgery Database Congenital Section. The outcome of interest was a composite end point of all-cause death and major complications within 30 days after surgery. We evaluated the association between body weight at surgery and composite end point using logistic regression models. Results: A total of 4947 cases were analyzed (median age, 125; interquartile range [IQR], 79-193 days; median body weight, 4.94 [IQR, 4.00-6.00] kg), including 4310 cases (87.1%) treated with surgical VSD closure and 637 (12.9%) treated with pulmonary artery banding. The surgical course was uncomplicated in 94.2% of cases, 23 (0.5%) died, and 283 (5.7%) experienced major complications. The risk of the composite end point was higher along with lower body weight (adjusted odds ratio, 1.56 for every −1 kg; 95% confidence interval, 1.30-1.88; P <.001) and plateaued at body weight of approximately >4.5 kg via smoothing spline curve. Importantly, cases with approximately <4.5 kg of body weight had higher predicted risk regardless of age. Conclusions: Surgical intervention for infants with VSD was safely performed in contemporary practice; however, caution is warranted in lower body weight infants, particularly for infants with approximately <4.5 kg.