Prognostic role of brain natriuretic peptide in acute pulmonary embolism

Background-Rapid, noninvasive, and accurate prognostic assessment with an inexpensive cardiac biomarker is an appealing approach for patients with acute pulmonary embolism (PE). Methods and Results-We measured at the time of admission the plasma level of plasma brain natriuretic peptide (BNP) to determine its utility in prognosticating the clinical course of 73 consecutive patients with acute PE. We used a prespecified BNP cut-off level (<90 pg/mL) for the prediction of the absence of a major adverse cardiovascular event, defined as any of the following: death, cardiopulmonary resuscitation, mechanical ventilation, or use of pressors, thrombolysis, catheter fragmentation, or surgical embolectomy. In the 20 (27%) patients with adverse events, median BNP (194.2, range 3.7 to 1201.1 pg/mL) was higher than in patients with a benign course (39.1, range 1.0 to 1560.0 pg/mL; P<0.001). However, 3 patients with adverse outcomes had low BNP levels on admission: 1 death, BNP 52 pg/mL; 1 patient with prolonged cardiopulmonary resuscitation, BNP 3.7 pg/mL; and 1 patient undergoing rescue thrombolysis, BNP 75 pg/mL. Sensitivity, specificity, and negative and positive predictive value of BNP levels <90 pg/mL for absence of adverse outcomes were 85% (64% to 95%), 75% (62% to 85%), 93% (95% CI 81% to 98%), and 57% (39% to 73%), respectively. The optimal BNP cut-off level, identified by receiver operating characteristic analysis, was <50 pg/mL. Conclusions-Low BNP levels do not guarantee an uncomplicated hospital course in patients with acute PE, using a "congestive heart failure" cut-off level of 90 pg/mL. A lower cut-off level of <50 pg/mL identifies 95% of patients with a benign clinical course.