Plasma Brain Natriuretic Peptide as a Prognostic Indicator in Patients With Primary Pulmonary Hypertension

Abstract

Background —Plasma brain natriuretic peptide (BNP) level increases in proportion to the degree of right ventricular dysfunction in pulmonary hypertension. We sought to assess the prognostic significance of plasma BNP in patients with primary pulmonary hypertension (PPH). Methods and Results —Plasma BNP was measured in 60 patients with PPH at diagnostic catheterization, together with atrial natriuretic peptide, norepinephrine, and epinephrine. Measurements were repeated in 53 patients after a mean follow-up period of 3 months. Forty-nine of the patients received intravenous or oral prostacyclin. During a mean follow-up period of 24 months, 18 patients died of cardiopulmonary causes. According to multivariate analysis, baseline plasma BNP was an independent predictor of mortality. Patients with a supramedian level of baseline BNP (≥150 pg/mL) had a significantly lower survival rate than those with an inframedian level, according to Kaplan-Meier survival curves ( P <0.05). Plasma BNP in survivors decreased significantly during the follow-up (217±38 to 149±30 pg/mL, P <0.05), whereas that in nonsurvivors increased (365±77 to 544±68 pg/mL, P <0.05). Thus, survival was strikingly worse for patients with a supramedian value of follow-up BNP (≥180 pg/mL) than for those with an inframedian value ( P <0.0001). Conclusions —A high level of plasma BNP, and in particular, a further increase in plasma BNP during follow-up, may have a strong, independent association with increased mortality rates in patients with PPH.