Right Ventricular Function Improves With Pulmonary Vasodilator Treatment in Pediatric Patients With Pulmonary Hypertension and Multivessel Pulmonary Vein Stenosis in a Single Center Cohort.

Abstract

Pulmonary hypertension (PH) and right ventricular (RV) dysfunction increase mortality in multivessel pediatric pulmonary vein stenosis (PVS). Pulmonary vasodilator use is limited in PVS due to the perceived risk of pulmonary edema. We aimed to describe our experience with pulmonary vasodilators in PVS and to assess changes in RV function and hemodynamics over time. Children with multi-vessel PVS (≥ 2 veins), mean pulmonary artery pressure > 20 mmHg, indexed pulmonary vascular resistance > 3 iWU, without single ventricle physiology, treated with pulmonary vasodilators from 2014 to 2024 were included in a single center, retrospective case series. RV systolic function was quantified by tricuspid annular plane systolic excursion (TAPSE), fractional area change (RVFAC), and longitudinal and free wall strain (RVLS, RVFWS). A four-point PVS severity score was calculated from angiographic data. RV function and hemodynamics were compared from baseline to the most recent by Wilcoxon rank sum tests, controlling for change in PVS severity score. Thirty-one patients (median (IQR) gestational age 27.1 (26.0, 35.9) weeks, birth weight 770 (540, 1900) grams) met the inclusion criteria. Median follow-up was 27.0 (10.5, 71.5) months. Most (65%) had Group 3, lung disease-related PH. One patient developed pulmonary edema requiring medication discontinuation. TAPSE, RVFAC, RVLS, and RVFWS improved significantly (p < 0.01 for all), independent of change in PVS severity score. Survivors demonstrated improved RV function compared to non-survivors. Hemodynamics were unchanged. Pulmonary vasodilators may improve RV function in patients with PVS and PH in a rigorous surveillance program. The impact of improved RV function on mortality in PVS deserves further study.