N-Terminal Pro-B-Type Natriuretic Peptide as a Prognostic Marker in Acute Coronary Syndrome

ABSTRACT

BACKGROUND AND OBJECTIVES: Biochemical markers are useful for the prediction of cardiac events in patients with acute coronary syndrome (ACS). The N-terminal fragment of the BNP prohormone (NT-proBNP), which is synthesized by cardiac ventricles in response to increased wall stress, may be a prognostic marker in ACS. The relation between the NT-pro BNP levels on admission and major adverse cardiovascular events (MACEs) were assessed in a cohort of patients with ACS. SUBJECTS AND METHODS: Between October 2002 and April 2004, blood samples for the determination of NT-proBNP level were obtained on admission from 78 patients with ST-elevation myocardial infarction (STEMI), 32 with non-ST elevation MI(NSTEMI) and 66 with unstable angina (UA). Patients were followed concerning MACEs (death, MI, heart failure, stroke and revascularization) for a median of 7 months in median. RESULTS: 22 patients (13%) had events. The mean NT-proBNP level was significantly lower in the event-free survivors than in those with events (1342+/-1598 versus 6129+/-6522 pg/mL, p<0.0001). The optimal cut-off value of the NT-proBNP level using a receiver-operating-characteristic curve was 1445 pg/mL. The unadjusted risk ratio of patients with an NT-proBNP level greater than the threshold was 7.0 (95% confidence interval, 2.6 to 19.0). In a multivariate Cox regression model, including clinical background factors and other biochemical markers, the NT-proBNP level was the most powerful indicator of MACEs (risk ratio, 8.0 [95% confidence interval, 1.7 to 37.1]). The coronary angiographic Gensini score was also a predictor of prognosis in ACS (risk ratio, 3.8 [95% confidence interval, 1.0 to 14.0]). CONCLUSION: A single measurement of the NT-proBNP level on admission appears to be useful as a prognostic factor in the prediction of MACEs in patients after ACS.