Background: 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.
Aim: To study the correlation of BNP with functional status and non-invasive hemodynamic determinations in patients with PPH.
Material and methods: 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.
Results: 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.
Conclusions: 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.