Improved hemodynamics and cardiopulmonary function in patients with inoperable chronic thromboembolic pulmonary hypertension after balloon pulmonary angioplasty.

Background: Balloon pulmonary angioplasty (BPA) has been demonstrated to improve cardiac function and exercise capacity in patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH), but its instant impact on cardiopulmonary function has seldom been evaluated. This study aims to determine the safety and efficacy of BPA and its immediate and lasting effects on cardiopulmonary function among CTEPH patients.

Methods: From May 2018 to January 2019, patients with inoperable CTEPH who underwent BPA sessions were consecutively enrolled. Hemodynamics were measured by right heart catheterization, selective pulmonary angiography and BPA were successively conducted. Hemodynamic variables, WHO functional class (WHO-FC), 6-min walk distance (6MWD) and serum NT-proBNP were evaluated before and after BPA sessions during hospitalization. Pulmonary function testing (PFT) and cardiopulmonary exercise testing (CPET) were performed within 1-3 days pre and post BPA to evaluate the effect of BPA on cardiopulmonary function.

Results: Twenty-five patients with inoperable CTEPH who underwent a total of forty BPA sessions were consecutively enrolled. A total of 183 segmental or subsegmental vessels (4.6 ± 1.9 vessels per session) in 137 segments (3.4 ± 1.6 segments per session) were dilated. No procedure-related complications occurred. Instant hemodynamics, WHO-FC, 6MWD and NT-proBNP were all significantly improved after a single BPA session. Significant improvement in cardiopulmonary function was also evident as assessed by PFT indexes (forced vital capacity, forced expiratory volume in the first second, maximal voluntary ventilation) and CPET parameters (peak work rate, peak VO, oxygen uptake efficiency slope). Further analysis among ten CTEPH patients receiving multiple BPA sessions (2-4 sessions) indicated BPA resulted in lasting improvements in hemodynamics and cardiopulmonary function.

Conclusions: BPA, a safe and effective approach, can bring instant improvements after a single session and lasting benefits after multiple sessions to hemodynamics and cardiopulmonary function for patients with inoperable CTEPH.