P2608Efficacy of percutaneous transluminal pulmonary angioplasty for chronic pulmonary thromboembolism without pulmonary hypertension

Abstract

Introduction: Percutaneous transluminal pulmonary angioplasty (PTPA/ balloon pulmonary angioplasty: BPA) has been demonstrated to improve symptoms and hemodynamic parameters in patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH). However, Efficacy of PTPA for chronic pulmonary thromboembolism (CPTE) without pulmonary hypertension (PH) has not been clarified yet. Purpose: The purpose of this study was to investigate the effectiveness of PTPA for CTPE without PH on pulmonary hemodynamics, oxygenation and exercise capacity. Methods: Patients with dyspnea on effort of more than New York Heart Association functional class (NYHA) II, less than 25mmHg of mean pulmonary artery pressure (PAP) in right heart catheterization, organized thrombi in pulmonary angiography and segmental multiple defects in VQ scan were defined as CPTE without PH. This study retrospectively included 20 patients with CPTE without PH before the treatment, who underwent PTPA by May 2016. Hemodynamic parameters such as PAP, pulmonary vascular resistance (PVR) and cardiac index (CI), pO2, and 6-minute-walk distance (6MWD) were compared between before and after PTPA. All data were expressed by median [25th percentile - 75th percentile]. Results: The median age, the number of PTPA sessions performed per person and dilated vessels per person were 65 [58-73] years old, 2 [2-3] and 11.5 [8.3-14.5] respectively. PTPA did not cause complications in all patients. Hemodynamic parameters such as PAP and PVR significantly improved after PTPA as compared with the baseline, but CI did not significantly (PAP: 21 [20- 22] to 17 [14-21] mmHg, P value <0.01; PVR: 2.8 [1.9-3.1] to 1.5 [1.2-1.8], P value <0.001, CI: 3.2 [2.8-3.4] to 3.4 [3.0-4.0], P value >0.05). Oxygenation and 6MWD were improved after PTPA (pO2: 69.3 [66.7-76.1] to 74.7 [65.7- 89.3] mmHg, P value <0.05; 6MWD: 377 [333-430] to 401 [360-444]m, P value <0.05). Ambulatory oxygen therapy (AOT) and PH-targeted drug free rates were reduced significantly (before vs. after; AOT: 80 to 45%, P value <0.05; PHtargeted drug free rate: 75 to 25%, P<0.01). Conclusions: PTPA can safely improve patients with CPTE without PH through oxygenation ameliolation.