['Plasma levels of brain natriuretic peptide (BNP) are increased in patients with left heart failure. In patients with severe pulmonary embolism (PE), primary right ventricular (RV) dysfunction is frequent. Little is known about BNP secretion in acute RV failure.', 'We prospectively studied 50 consecutive patients with confirmed PE (age range, 57 +/- 19 years; 36 men). PE was confirmed with pulmonary angiography, spiral computed tomography, or echocardiography and subsidiary analyses. On admission, echocardiography and BNP measurements were performed in all patients.', 'Patients without RV dysfunction had significantly lower BNP levels than patients with RV dysfunction (55 +/- 69 pg/mL vs 340 +/- 362 pg/mL, P <.001). There was a significant correlation between RV end-diastolic diameter and BNP (r = 0.43, P <.05). BNP discriminated patients with or without RV dysfunction (area under the receiver operating characteristic curve, 0.78; 95% CI, 0.64-0.92). A BNP >90 pg/mL was associated with a risk ratio of 28.4 (95% CI, 3.22-251.12) for the diagnosis of RV dysfunction. All patients without LV systolic dysfunction who had syncope necessitating cardiopulmonary resuscitation had normal BNP levels. Patients with RV dysfunction had significantly more in-hospital complications (cardiogenic shock, inotropic therapy, mechanical ventilation). However, BNP levels were not predictive of mortality or in-hospital complications.'] Does brain natriuretic peptide predict right heart failure in patients with acute pulmonary embolism?