Brain-type natriuretic peptide levels in the prediction of adverse outcome in patients with pulmonary embolism - A systematic review and meta-analysis

Rationale: The potential role of elevated brain-type natriuretic peptides (BNP) in the differentiation of patients suffering from acute pulmonary embolism at risk for adverse clinical outcome has not been fully established. Objectives: We evaluated the relation between elevated BNP or N-terminal-pro-BNP (NT-pro-BNP) levels and clinical outcome in patients with pulmonary embolism. Methods: Articles reporting on studies that evaluated the risk of adverse outcome in patients with pulmonary embolism and elevated BNP or NT-pro-BNP levels were abstracted from Medline and EMBASE. Information on study design, patient and assay characteristics, and clinical outcome was extracted. Primary endpoints were overall mortality and predefined composite outcome of adverse clinical events. Measurements and Main Results: Data from 13 studies were included. In 51% (576/1,132) of the patients, BNP or NT-pro-BNP levels were increased. The different analyses were performed in subpopulations. Elevated levels of BNP or NT-pro-BNP were significantly associated with right ventricular dysfunction (P < 0.001). Patients with high BNP or NT-pro-BNP concentration were at higher risk of complicated in-hospital course (odds ratio [OR], 6.8; 95% confidence interval [CI], 4.4-10) and 30-day mortality (OR, 7.6; 95% CI, 3.4-17). Patients with a high NT-pro-BNP had a 10% risk of dying (68/ 671; 95% CI, 8.0-13%), whereas 23% (209/909; 95% CI, 20-26%) had an adverse clinical outcome. Conclusions: High concentrations of BNIP distinguish patients with pulmonary embolism at higher risk of complicated in-hospital course and death from those with low BNP levels. Increased BNP or NT-pro-BNP concentrations alone, however, do not justify more invasive treatment regimens.