Value of NT-ProBNP level and echocardiographic parameters in ST-segment elevation myocardial infarction treated by primary angioplasty: relationships between these variables and their usefulness as predictors of ventricular remodeling.

INTRODUCTION AND OBJECTIVES: To assess the value of N-terminal fragment of brain natriuretic peptide (NT-proBNP) measurement and echocardiography for predicting ventricular remodeling after myocardial infarction and to investigate relationships between the NT-proBNP level and echocardiographic parameters at discharge and in the medium term.

METHODS: The study involved 159 patients with myocardial infarction treated by primary coronary angioplasty. The NT-proBNP level was measured on admission, at discharge and after 6 months. Echocardiography was performed at discharge and after 6 months.

RESULTS: Overall, 31 patients (19.5%) demonstrated remodeling. At discharge, the variables associated with remodeling were: mitral inflow E-wave-to-A-wave velocity ratio (E/A), systolic mitral annulus velocity (Sm), early diastolic mitral annulus velocity (Em), the mitral inflow E wave to early diastolic mitral annulus velocity ratio (E/ Em), left atrial volume (LAV), left ventricular end-systolic volume (LVESV), left ventricular end-diastolic volume (LVEDV), and discharge NT-proBNP level. Only E/Em was an independent predictor of ventricular remodeling (odds ratio [OR]=1.143; 95% confidence interval [CI], 1.039-1.258; P=.006). At discharge, correlations were observed between the NT-proBNP level and LVEDV, LVESV, ejection fraction (EF) and E/Em. At 6 months, correlations with ventricular volumes and EF were unchanged, the correlation with E/Em was better (r=0.47 vs. r=0.69), and a modest correlation with LAV developed (r=0.43; P=.001).

CONCLUSIONS: The E/Em ratio was the best echocardiographic predictor of left ventricular remodeling after myocardial infarction. The NT-proBNP level had no additional predictive value over echocardiography. Correlations between the NT-proBNP level and ventricular volumes and EF at discharge and 6 months were similar, while correlations with E/Em and LAV were better at 6 months.