Survival of Japanese Patients With Idiopathic/Heritable Pulmonary Arterial Hypertension

Abstract

Idiopathic/heritable pulmonary arterial hypertension has a poor prognosis despite the available therapeutic options. Survival of Japanese patients with this disease entity has not been reported in the multicenter setting. A retrospective study of 141 patients with idiopathic/heritable pulmonary arterial hypertension treated at 3 pulmonary hypertension centers in Japan from 1992 to 2012 investigated survival and determinants of survival. Mean survival time from treatment initiation was 14.7 ± 0.8years (95% confidence interval, 13.1 to 16.3years) and the 1-, 3-, 5-, and 10-year survival rates were 97.9%, 92.1%, 85.8%, and 69.5%, respectively. Patients showed significant improvement in exercise capacity and hemodynamics after treatment. Patients with 6-minute walk distance >372m, mean pulmonary arterial pressure ≤46mm Hg, and cardiac index >2.5L/min/m2 at follow-up had a significantly better prognosis. Most patients (99.2%) were receiving pulmonary hypertension-targeted drugs at follow-up. Use of endothelin receptor antagonists and intravenous epoprostenol were related to survival in the univariate analysis. Among thepatients who were on intravenous epoprostenol therapy, those with endothelin receptorantagonists had a significantly better prognosis, whereas patients on warfarin hada significantly worse prognosis. In conclusion, survival of Japanese patients with idiopathic/heritable pulmonary arterial hypertension in this study was good, showing improvement in hemodynamic parameters supported by pulmonary hypertension-targeted drugs.