Outcomes after Decompression of the Right Ventricle in Infants with Pulmonary Atresia with Intact Ventricular Septum Are Associated with Degree of Tricuspid Regurgitation: Results from the Congenital Catheterization Research Collaborative

Background - Outcomes after right ventricle (RV) decompression in infants with pulmonary atresia with intact ventricular septum vary widely. Descriptions of outcomes are limited to small single-center studies. Methods and Results - Neonates undergoing RV decompression for pulmonary atresia with intact ventricular septum were included from 4 pediatric centers. Primary end point was reintervention post-RV decompression; secondary end points included circulation type at latest follow-up. Ninety-nine patients (71 with pulmonary atresia with intact ventricular septum and 28 with virtual atresia) underwent RV decompression at median 3 (25th-75th, 2-5) days of age. Seventy-one patients (72%) underwent at least 1 reintervention after decompression. Median duration of follow-up was 3 years (range, 1-10). Freedom from reintervention was 51% at 1 month and 23% at 3 years. In multivariable analysis, reintervention was associated with virtual atresia (hazard ratio [HR], 0.51; 95% confidence interval [CI], 0.28-091; P=0.027), smaller RV length (HR, 0.94; 95% CI, 0.89-0.99; P=0.027), and ≤mild tricuspid regurgitation (TR; HR, 3.58; 95% CI, 2.04-6.30; P<0.001). Patients undergoing surgical shunt or ductal stent were less likely to have virtual atresia (HR, 0.36; 95% CI, 0.15-0.85; P=0.02) and more likely to have higher RV end-diastolic pressure (HR, 1.07; 95% CI, 1.00-1.15; P=0.057) and ≤mild TR (HR, 3.50; 95% CI, 1.75-7.0; P<0.001). Number of reinterventions was associated with ≤mild TR (rate ratio, 1.87; 95% CI, 1.23-2.87; P=0.0037). Multivariable analysis indicated that <2-ventricle circulation status was associated with ≤mild TR (odds ratio, 18.6; 95% CI, 5.3-65.2; P<0.001) and lower RV area (odds ratio, 0.81; 95% CI, 0.72-0.91; P<0.001). Conclusions - Patients with pulmonary atresia with intact ventricular septum deemed suitable for RV decompression have a high reintervention burden although most achieve 2-ventricle circulation. TR ≤mild at baseline is strongly associated with reintervention and <2-ventricle circulation at medium-term follow-up. Degree of baseline TR may be an important marker of long-term outcomes in this population.