B-type natriuretic peptide levels predict extent and severity of coronary artery disease in non-ST elevation acute coronary syndrome and normal left ventricular function.

BACKGROUND: B-type natriuretic peptide has been used as a biological marker for prognosis in patients with acute coronary syndrome (ACS). However, a relation between the quantity of BNP levels and the severity of coronary artery disease has not been systematically evaluated.

METHODS: 197 patients with ACS without ST elevation with normal LV systolic function were enrolled. BNP was measured in all recruited patients within 12 h of hospitalization. All patients underwent coronary angiography. We correlated BNP levels in patients with unstable angina (USAP) and non ST-elevation myocardial infarction (NSTEMI) with angiographic disease severity including Gensini Score.

RESULTS: BNP levels were significantly higher in the NSTEMI group in comparison to the USAP Group (161 ± 149.3 vs 79.6 ± 94.2 pg/mL; p < 0.001). BNP levels rose significantly with increasing number of vessels involved (1-vessel = 51.4 ± 31.6; 2-vessels = 114.0 ± 67.8; 3 vessels = 265.4 ± 188.8 pg/mL, p < 0.001). Most importantly, BNP> 80 pg/ml was found to strongly predict the presence of Triple vessel disease (odds ratio 18.87; 95% confidence intervals 5.36-66.36), and Double vessel disease (odds ratio 3.62; 95% confidence intervals 1.75-7.47). In single vessel group, BNP was significantly higher when LAD was involved vessel (64.78 vs 49.76 pg/mL, p < 0.05). Gensini Score showed a strong correlation with BNP levels (r = 0.675, p < 0.01), and Gensini Score was significantly higher in those with BNP> 80 pg/ml (40.9 ± 29.7 vs 13.4 ± 16.5 p < 0.001).

CONCLUSION: Circulating BNP levels appear elevated in Non ST Elevation ACS, even in the absence of LV systolic dysfunction. High BNP levels are associated with multi-vessel disease and diffuse coronary atherosclerosis.