B-type natriuretic peptide blood levels identify patients with non-ST elevation acute coronary syndromes at high risk for complications during intravenous beta-blocker infusion.

Background: We hypothesized that measurement of B-type natriuretic peptide could identify patients with non-ST elevation acute coronary syndromes at high risk for complications during beta-blocker (esmolol) infusion.

Methods: We reviewed the records of 340 consecutive patients admitted with a non-ST elevation acute coronary syndrome. Seventy three (47 males, aged 62 ± 14 years) received esmolol up to a maximum dose of 300 μg/ kg/min until the symptoms were relieved or an adverse event occurred.

Results: The median infusion rate at steady state was 175 μg/kg/min (median infusion time 18 h). Infusion was halted in 14 patients. The frequency of drug discontinuation increased across admission BNP quartiles. BNP > 141 pg/ml at admission had a 95% predictive value for subsequent withdrawal of esmolol. The presence of BNP > 141 pg/ml in combination with systolic blood pressure < 130 mmHg and left ventricular ejection fraction < 50% identified a group of patients at high risk for drug interruption (interruption frequency = 83%, 95% CI: 55-95%).

Conclusions: In conclusion, BNP measurement in combination with systolic blood pressure and 2D echocardiography may identify patients with non-ST elevation acute coronary syndromes at high risk for adverse events during esmolol infusion.