Outcome of patients with severe PH due to lung disease with and without targeted therapy.

Abstract

Pulmonary hypertension (PH) can occur in patients with lung disease and worsen prognosis. Endothelin receptor antagonists, phosphodiesterase 5-inhibitors, and prostacyclin analogs, referred to as targeted therapy, have not been shown in a limited number of controlled clinical studies to improve exercise capacity in these patients. Possibly targeted therapy could be of benefit in patients with severe PH due to lung disease, but this subgroup is not well studied. To analyze influence of PH severity and use of targeted therapy on exercise capacity and survival in patients with PH due to lung disease. Consecutive patients with PH (mean pulmonary artery pressure ≥25mmHg at rest) due to lung disease diagnosed by right heart catheterization between 1/2005 and 9/2011 were retrospectively included. Severe PH was defined as mean pulmonary artery pressure ≥35mmHg. Patients were followed until 4/2012 for exercise capacity, survival, and targeted therapy use. Patients with severe PH (n=40) received significantly more often targeted therapy compared to the 32 patients with less severe PH (65% vs. 25%, P=0.001). Survival was not significantly different between these groups (P=0.310). Patients on targeted therapy were older, more often female, and had worse hemodynamic impairment, but significantly higher estimated 1-, 3-, and 5-year survival rates compared to untreated patients (97%, 81%, and 75% vs. 83%, 54%, and 19%, respectively; P=0.002). This effect was mainly driven by the patients with severe PH, in whom the survival advantage was statistically significant on subgroup analysis (HR 0.182, P=0.002). Exercise capacity was not significantly altered in any patient group. Patients with severe PH due to lung disease may have a survival benefit from targeted therapy compared to untreated patients with less severe PH. Prospective clinical trials utilizing targeted therapy and long-term endpoints are justified in this patient group.