Natriuretic peptides as predictors of non-sudden and sudden cardiac death after acute myocardial infarction in the beta-blocking era

OBJECTIVES: This prospective study tested whether the natriuretic peptides predict cardiac death among patients using beta-blocking therapy after an acute myocardial infarction (AMI). BACKGROUND: Natriuretic peptides have provided prognostic information after AMI, but their predictive value has not been well established in the era of beta-blocker use. METHODS: A series of 521 patients (mean age 61 +/- 10 years) with AMI was included in the study. The end points were total mortality and non-sudden and sudden cardiac death (SCD). Plasma concentrations of atrial natriuretic peptide (ANP), N-terminal atrial natriuretic propeptide (N-ANP), brain natriuretic peptide (BNP), and ejection fraction (EF) were analyzed before hospital discharge. The cardiac medication was optimized (e.g., adherence to beta-blocking therapy was 97% at discharge and 95% at one year after AMI). RESULTS: During a mean follow-up of 43 +/- 13 months, total mortality was 11.5% (60/521), cardiac mortality was 6.3% (33/521), and 3.1% (16/521) experienced SCD. On univariate analysis, high levels of all measured peptides and low EF predicted the occurrence of non-SCD (p < 0.001 for all). Peptides and EF also predicted the occurrence of SCD (p < 0.05), with elevated BNP (>23.0 pmol/l) being the most powerful predictor (hazard ratio [HR] 4.4, 95% confidence interval [CI] 1.4 to 13.8; p = 0.01). After adjusting for clinical variables, only elevated BNP (HR 3.9, 95% CI 1.2 to 12.3, p = 0.02) and low EF (<40%) (p = 0.03) remained as significant predictors of SCD. CONCLUSIONS: Natriuretic peptides retain their prognostic value in the beta-blocking era among survivors of AMI. Elevated BNP provides information on the risk of subsequent SCD, independent of clinical variables and left ventricular EF.