Plasma brain natriuretic peptide (BNP) increase is associated with acute right ventricular dysfunction in pulmonary embolism

Right ventricular dysfunction (RVD) is critical for risk stratification of patients with pulmonary embolism (PE). Evaluation can be made by echocardiography or biological markers among which plasma levels of brain natriuretic peptide (BNP). The aim of our study is assessment of BNP levels in patients with PE associating or not RVD as diagnosed by classic echocardiographic criteria. We prospectively assessed 40 patients with deep venous thrombosis and confirmed PE (age range 52.5 ± 9.14 years, 22 men and 18 women), with (14) or without (26) RVD on echocardiography. Plasma BNP levels were significantly higher in RVD patients (190 ± 171.2 pg/mL vs. 15.75 ± 18.85 pg/mL, P < 0.0001). A cut-off level of plasma BNP = 50 pg/mL had a sensitivity, specificity, positive and negative predictive value for the diagnosis of RVD of 84% (C.I. 79% - 88%), 80% (C.I. 75% - 85%), 83% (C.I. 77% - 87%) and 79% (C.I. 75% - 84%), respectively. There was a significant correlation between plasma BNP levels and end-diastolic RV diameter (r = 0.56, P < 0.0001), RV systolic pressure (r = 0.50, P < 0.001) and the presence of a Qr complex in V 1 -lead on ECG (r = 0.55, P < 0.05). Four patients with RVD on echocardiography and syncope, all admitted relatively soon after the onset of their symptoms, had BNP in normal range. In conclusion, PE should be considered in the differential diagnosis of patients with dyspnoea and increased plasma BNP levels. A cut-off level of 50 pg/mL could identify the RVD in patients with PE with a good sensitivity and specificity. Normal range plasma BNP levels do not exclude even a severe PE and should be interpreted with caution, especially in highly symptomatic patients with recent symptom onset.