Impact of Pulmonary Capillary Wedge Pressure on Long-Term Mortality in Patients With Pulmonary Arterial Hypertension Treated With Parenteral Trepostinil

Abstract

The clinical impact of pulmonary capillary wedge pressure (PCWP) on long-term mortality among patients with pulmonary arterial hypertension (PAH) has been incompletely reported, particularly in relation to concomitant treprostinil administration. The goal of this study was to assess the impact of PCWP on long-term mortality in PAH patients treated with parenteral treprostinil. We studied a cohort of 743 patients with PAH treated with parenteral treprostinil therapy. The long-term all-cause mortality was compared in patients with baseline mean PCWP≤8mmHg, 8<PCWP≤11mmHg, and PCWP>11mmHg over 4-year follow-up. Of the 743 patients studied, 280 patients (37.7%) had a baseline mean PCWP ≤ 8mmHg, 233 patients (31.4%) had a mean PCWP of >8mmHg and ≤11mmHg, and 230 patients (31.0%) had a mean PCWP >11mmHg. While patients with higher PCWP had higher mean right atrial and PA pressures, no difference was noted in cardiac output and pulmonary vascular resistance (PVR). All-cause mortality was similar between patients with PCWP≤8mmHg, 8<PCWP≤11mmHg, and PCWP>11mmHg at 1 year (10.4% vs 9.9% vs 10.0%, p=0.980) and 4 years (16.8% vs 21.9% vs 19.2%, p=0.353) respectively. In multivariate analysis, PCWP was not independently predictive of 4-year all-cause mortality [HR 1.00, 95%CI 0.95-1.05, p=0.98 (permmHg)]. Predictors of 4-year mortality included older age [HR 1.02, 95%CI 1.00-1.03, p=0.0091 (per year)], non-​Caucasian race, and higher PVR [HR 1.06, 95% CI 1.04-1.08, p<0.0001 (per Woods Unit)]. In this study of patients with PAH receiving parenteral treprostinil, PCWP was not associated with long-term all-cause mortality. Further studies examining prognostic indicators in patients with PAH optimised on guideline-based therapies are warranted.