Does elevated NT-proBNP predict significant coronary artery disease in unstable angina patients with normal ECG, echocardiogram, and cardiac enzymes?
In patients with unstable angina and normal ECG, echocardiogram, and cardiac enzymes, an elevated NT-proBNP level (>200 pg/ml) is a strong independent predictor of significant coronary artery disease.
BACKGROUND: Brain natriuretic peptide (BNP) and N-terminal pro-brain natriuretic peptide (NT-proBNP) are not specific for ventricular dysfunction and other cardiac processes, such as myocardial ischemia, may also cause elevation of these markers. METHODS AND RESULTS: To determine whether elevation of NT-proBNP without elevation of cardiac specific markers can predict coronary artery disease (CAD), the serum level of NT-proBNP was measured in 161 patients with unstable angina (61.0+/-8.1 years, male 54.0%) with normal ventricular function (left ventricular ejection fraction >55% and no regional wall motion abnormality by echocardiography) and normal troponin I level (200 pg/ml, elevated NT-proBNP level shows high probability of CAD (odds ratio, 10.1; 95% confidence interval, 2.6-38.7, p=0.001). The NT-proBNP level positively correlated with the extent of CAD (r=0.329, p=0.001). In multivariate analysis, the NT-proBNP was an independent predictor of CAD. CONCLUSION: These results suggested that NT-proBNP is a useful screening test for CAD in the unstable angina patients with normal ECG, echocardiogram and cardiac enzyme levels.
Hong et al. (2005) studied this question.