Right atrial volume and reservoir function are novel independent predictors of clinical worsening in patients with pulmonary hypertension

Abstract

Symptoms and signs and indices of right heart function are predictors of clinical outcomes in patients with pulmonary hypertension (PH). However, the significance of right atrial (RA) indices has not been sufficiently investigated. We investigated whether RA parameters predict outcomes in patients with pre-capillary PH. Study subjects were 68 patients with pre-capillary PH. RA size and function (systolic, reservoir, and conduit functions) were evaluated by cardiac magnetic resonance imaging. During the mean follow-up period of 24 months, 16 of 68 patients experienced clinical worsening (CW), defined as hospitalization because of right heart failure, lung transplantation, or PH-related death. Kaplan-Meier and log-rank test showed that World Health Organization functional class, pericardial effusion, increased brain natriuretic peptide concentration, reduced right ventricular ejection fraction (RVEF), increased minimum RA volume index, and decreased RA reservoir volume were associated with CW-free survival. The combination of RVEF and RA reservoir function was a better predictor of CW-free survival. In univariate Cox hazard proportional analysis, CW was associated with the RA reservoir volume index (hazard ratio [HR] = 0.80). In multivariate analysis, CW was associated with World Health Organization functional class (HR = 4.3), RA minimum volume index (HR = 1.07), and RA reservoir volume index (HR = 0.73). RA volume and reservoir function and their combined use with RVEF are novel predictors of CW in patients with pre-capillary PH.