Plasma brain natriuretic peptide (BNP), which serves as a noninvasive marker of left-side heart failure, was recently reported to increase in proportion to right ventricular dysfunction in patients with pulmonary hypertension. Pro BNP is a prohormone cleaved into the inactive N terminal portion (NT pro-BNP) and the active BNP. The aim of this study was to determine whether the NT pro- BNP is a potential indicator of the disease severity for pulmonary hypertension and may be a guide for efficacy of treatment.
Forty-three patients with a diagnosis of pulmonary arterial hypertension being followed at our clinic.All patients underwent right heart catheterization and clinical assessment. Treatment consisted of vasodilators. Blood was drawn for the measurement of NT pro-BNP, and findings were correlated with hemodynamic parameters (mean pulmonary arterial pressure, cardiac index), clinical factors (6-min walk, New York Heart Association class) and 6-month outcome.
Two patients died of the disease during the follow-up period. Plasma NT pro-BNP level was found to be a significant predictor of mortality (r=-0.7, p<0.0001) and correlated with New York Heart Association class (r= 0.2, p= 0.06). Division of the patients by etiology yielded higher NT pro-BNP levels in those with idiopathic pulmonary hypertension than in the other groups (pulmonary hypertension associated with collagen vascular disease, chronic pulmonary emboli, Eisenmenger syndrome) (r=-0.3, p= 0.02). No statistical significant correlation was found between plasma NT pro-BNP level and distance in the 6-min walk( r=-0.2, p=0.11).
A high plasma NT pro-BNP level is strongly associated with increased mortality in patients with pulmonary hypertension and suggests the need for aggressive treatment.
Further studies are warranted to evaluate the role of NT pro-BNP as a biological marker to replace right heart cathetrization. Repeated measurement may be helpful as a guide for selecting therapy.
Daniele Bendayan, None.