Effects of percutaneous transluminal pulmonary angioplasty on respiratory functions in patients with chronic thromboembolic pulmonary hypertension

Abstract

Background: Percutaneous transluminal pulmonary angioplasty (PTPA) is an emerging therapeutic strategy to improve hemodynamics with inoperable chronic thromboembolic pulmonary hypertension (CTEPH). Aim: We aimed to reveal the effects of PTPA on respiratory function in patients with inoperable CTEPH. Methods: From July 2011 to October 2014, 61 patients with inoperable CTEPH (median age 63 yrs., female 47/60 (78%)) underwent PTPA in our hospital. In 25 of them (41%), we examined respiratory functions, including %VC, FEV1.0%, %DLco, A-a DO 2 and intra-pulmonary shunt before and after PTPA procedure. Intra-pulmonary shunt was calculated using blood samples during administration of pure oxygen. Results: Mean pulmonary arterial pressure (mPAP), saturation of oxygen (SatO 2 ) measured in room air, and A-a DO 2 were significantly improved after PTPA(mPAP, 40±10 to 26±6 mmHg, P 2 ,87±6 to 90±6%, P 2 after PTPA (n=13, 52%), those showing 2 had greater extent of intra-pulmonary shunt before and after PTPA (before, 28±8 vs. 22±5 %, P 2 =0.03, P=0.31), changes in mPAP and those in intrapulmonary shunt before and after PTPA were significantly correlated (r 2 =0.17, P=0.04). There were no significant effects of PTPA on %VC, FEV1.0% or %DLco. Conclusions: These results indicate that PTPA improves not only pulmonary hemodynamics but also oxygenation capacity with possible beneficial interactions.