N-terminal probrain natriuretic peptide (NT-proBNP) in the emergency diagnosis and in-hospital monitoring of patients with dyspnoea and ventricular dysfunction.

OBJECTIVE: To evaluate the utility of NT-proBNP in the emergency diagnosis and in-hospital monitoring of patients with acute dyspnoea and ventricular dysfunction. BACKGROUND: Misdiagnosis of heart failure (HF) is common in the urgent care setting using clinical diagnostic tests. Reports show that BNP is useful to diagnose HF in patients with acute dyspnoea. METHODS: Prospective study of 100 patients attending the Emergency Department (ED) for acute dyspnoea. Final diagnosis was determined on the basis of ED data sheets, echocardiography and pulmonary function tests. NT-proBNP levels were obtained on admission, at 24 h and at day 7. RESULTS: Patients with ventricular dysfunction were sub-classified into decompensated HF and masked HF, defined as HF with concomitant signs of pulmonary disease. Decompensated and masked HF patients had significantly higher NT-proBNP values than patients with non-cardiac dyspnoea (normal ventricular function) (920+/-140 and 978+/-363 vs. 50+/-15 pmol/L; P<0.001 and P<0.01, respectively). The mean area under the ROC curve for NT-proBNP was 0.957 (95% CI, 0.918 to 0.996, P<0.001). In multiple logistic-regression analysis NT-proBNP>115 pmol/l was the strongest independent predictor of ventricular dysfunction (odds ratio 45.4; 95% CI: 4.5-452.3). At day 7, a significant and similar reduction in NT-proBNP was observed in the two groups of patients with ventricular dysfunction (P<0.001 vs. admission values), but complete clinical resolution was less frequent in masked HF patients (P<0.05 vs. decompensated HF). CONCLUSIONS: NT-proBNP is a new candidate marker for the detection and exclusion of ventricular dysfunction in patients attending the ED for acute dyspnoea. NT-proBNP may also serve to monitor outcome during hospitalization.