[Brain natriuretic peptide in primary pulmonary hypertension]

Primary pulmonary hypertension (PPH) is a progressive disease leading to right heart failure and death. Right heart catherization and maximal or submaximal tests are employed to assess the course of the disease. A neurohormonal parameter such as pro-brain natriuretic peptide (BNP) would be helpful in the assessment of these patients.

To study the correlation of BNP with functional status and non-invasive hemodynamic determinations in patients with PPH.

Twelve patients (mean age: 48 years; 58% female) were evaluated with 6 minutes walk distance test (6-min WT), plasma BNP, systolic pulmonary artery pressure (PAP), pulmonary vascular resistance (PVR) and cardiac output (CO) determined by echocardiogram. Plasma BNP levels were compared with normal subjects.

BNP levels were increased in PPH patients (1270+/-547 vs 48+/-8 pg/ml, p-value <0.01). Mean PAPs was 82+/-27 mmHg and the mean distance walked in 6 minutes was 407+/-113 meters. BNP levels were positively correlated with PVR (r=0.58, p-value=0.006) and negatively correlated with 6-min WT (r=-0.83, p-value <0.001). No correlation was found between BNP levels, PAPs and CO.

In PPH patients, BNP levels are increased and correlate with functional class and PVR. Follow-up studies are needed to evaluate the role of BNP as a marker of progression and therapeutic response in PPH patients.