Abstract 15801: Early and Late Risk of Mortality or Development of Severe Pulmonary Hypertension Following Closure of Ventricular Septal Defects in Children With Severe Pulmonary Hypertension and Elevated Pulmonary Vascular Resistance Using Traditional or Uni-directional Flap Valve Patch Closure

Abstract

Introduction: Children with large ventricular septal defects, severe pulmonary hypertension (PHT), and elevated pulmonary vascular resistance (PVR) are frequently denied operation in low and middle-income countries secondary to concerns of high mortality and development of severe pulmonary hypertension following operation, early and late. Hypothesis: We hypothesized that closure with a uni-directional flap valve patch (DP) would provide lower mortality and better survival without severe PHT. Methods: From 5/96 - 12/2016 all patients undergoing VSD closure with severe PHT and elevated PVR by either traditional (TP) or DP closure were followed annually. Baseline and O 2 provocation catheterization were performed before operation. Echocardiograms were performed at discharge and follow-up. The decision on TP or DP closure was based upon age and surgeon preference. Beginning in 2005 all patients regardless of technique received sildenafil 3 mgs/kg/day for 3 months before operation. Results: The number of patients receiving operation was 129, of which 40 received the DP. Males were 66/129, age and weight differed significantly for DP group compared to the TP group (7.5 vs 2.6 years, p<0.001 and 20 vs 11.5 kgs, p<0.001).Catheterization baseline data, PVR 9.0 vs 7.4 for DP and TP respectively (p<0.001), negative vasoactive test 32.5% vs 13.5% for DP and TP respectively (p=0.016). Mortality was 1/40 for DP and 9/89 for TP. Pulmonary to Systemic systolic pressure ratio was lower at discharge vs baseline cath (0.38 vs 0.99, p<0.001). Predictors of late severe pulmonary hypertension were PVR/SVR >0.5, p<0.024; and a negative vasoactive test of <10% decrease, p<0.001. PHT at last follow-up, none or mild 86/115 (74.8%), moderate 16/115 (13.9%) or severe 13/115 (11.3%). Conclusions: DP patients had less risk of death and both groups had few patients with severe PHT at late follow-up..