Efficacy of pulmonary hypertension-targeted drugs for severe chronic thromboembolic pulmonary hypertension

Abstract Background High pulmonary vascular resistance (PVR) is a risk factor for reperfusion pulmonary edema by balloon pulmonary angioplasty (BPA). It has not been clarified whether improvement of hemodynamics by pulmonary hypertension (PH)-targeted drugs before BPA session is effective clinically. Severe chronic Thromboembolic pulmonary hypertension (CTEPH) patients have small vessel disease like pathological findings of idiopathic pulmonary arterial hypertension. Objectives The purpose of this study was to investigate the efficacy of PH-targeted drugs for patients with CTEPH before BPA. Methods This study included consecutive 147 CTEPH patients treated with PH-targeted drugs before BPA. All patients were divided into 2 groups such as severe group (PVR >12.5 wood units) and non-severe group (PVR <12.5 wood units). PVR were compared between baseline and after treated with PH-targeted drugs. All data were expressed by median [25thpercentile-75thpercentile]. Results The median age and male were 66 [53–74] years old and 42. Numbers of patients treated with phosphodiesterase V inhibitors, endothelin receptor antagonists and riociguat were 84 (57%), 92 (63%), and 43 (29%), respectively. PVR significantly decreased after treated with PH-targeted drugs in two groups (severe group: 16.3 [13.7–20.0] to 10.0 [7.2–13.3] wu, P<0.0001; non-severe group: 6.8 [4.9–8.9] to 5.7 [3.5] to 7.8, P<0.001). Changes of PVR in severe group were significantly larger than in non-severe group (−6.9 [−8.5 to −3.2] vs. −0.7 [−2.4 to 0.7], P<0.0001). There was no significant difference in efficacy of BPA and numbers of dilated vessel between two groups (severe vs. non-severe group after BPA; PVR: 2.7 [1.9–3.5] vs. 2.1 [1.7–3.1] wu, P>0.05; numbers of dilated vessel: 18 [14–21] vs. 16 [10–21], P>0.05) Conclusions PH-targeted drugs may improve hemodynamics for severe CTEPH more effectively.