Aminoterminal B-type pro-natriuretic peptide as a marker of recovery after high-risk coronary artery bypass grafting in patients with ischemic heart disease and severe impaired left ventricular function.

ABSTRACT

BACKGROUND: Aminoterminal B-type pro-natriuretic peptide (NT-proBNP) is a reliable indicator of heart failure severity. Levels of NT-proBNP are markedly increased in patients with coronary artery disease (CAD) and severely impaired left ventricular (LV) function. The aim of our study was to assess the impact of NT-proBNP levels after high-risk coronary artery bypass grafting (CABG) with regard to recovery potential. METHODS: Between 1998 and 2004, 121 patients with CAD and severely impaired LV function, who were undergoing CABG, were investigated. Their mean age was 64 +/- 11 years. All patients were in New York Heart Association (NYHA) Class III/IV status; LV ejection fraction (EF) was 20 +/- 6%. All survivors underwent follow-up (59 +/- 34 months) spiroergometric, electrocardiographic (ECG) and echocardiographic assessment and were tested for routine blood controls and NT-proBNP levels (Roche, Mannheim, Germany). RESULTS: The survival rate after 8 years was 70%. All survivors received follow-up assessment. Among survivors the median NT-proBNP level at follow-up was 896 (521 to 1,687) pg/ml. The maximum oxygen uptake was 14.6 +/- 4.9 ml/min/kg, and EF increased to 42% at follow-up among all survivors. On dichotomizing survivors into two groups with NT-proBNP levels above and below the median, the post-operative body mass index was significantly higher in the high NT-proBNP group (p = 0.036). EF (p = 0.028) and NYHA classification (p < 0.05) improved significantly in both groups, with a tendency toward higher EF in the low NT-proBNP group. CONCLUSIONS: Patients undergoing a high-risk CABG procedure have a survival rate comparable to heart transplantation patients and show a potential for clinical and myocardial recovery. NT-proBNP use a useful marker for recovery after a high-risk CABG procedure, with significant correlation with clinical parameters.