Usefulness of beta-blocker therapy and outcomes in patients with pulmonary arterial hypertension.

Pulmonary arterial hypertension (PAH) is a disorder in which pulmonary arterial remodeling and vasoconstriction progressively lead to right heart failure (HF), exercise intolerance, and high mortality. Beta-blockers have been shown to decrease mortality in left-sided HF, but their efficacy in isolated right HF associated with PAH is uncertain. Patients with PAH may have cardiac co-morbidities for which β-blocker therapy is indicated, and the relative risk benefit of this therapy remains to be proved. This is a prospective cohort study of 94 consecutive patients with PAH divided into 2 groups with and without β-blocker use at baseline. Rate of all-cause mortality, PAH-related hospitalization, change in 6-minute walk test, right ventricular structure and function measured by echocardiography, and hemodynamics measured by right heart catheterization were determined between subjects with and without β-blocker use. Beta-blocker use was common (28%) in this cohort. After a median follow-up of 20 months, changes in pulmonary hemodynamics and right ventricular size and function were similar between groups. There were no statistically significant differences in adverse events including PAH-related hospitalization or all-cause mortality (p = 0.19), presence of right HF by last visit (p = 0.75), or change in last 6-minute walk distance (p = 0.92). In conclusion, β-blocker use is not uncommon in a select group of patients with PAH and cardiac co-morbidities and did not appear to exert detrimental effects in clinical, functional, and hemodynamic outcomes. Further randomized data are needed to evaluate the potential benefits and risks of β-blocker use in patients with PAH.