Elevated serum heart-type fatty acid-binding protein in the convalescent stage predicts long-term outcome in patients surviving acute myocardial infarction

Background: Little is known about the prognostic significance of elevated serum heart-type fatty acid-binding protein (H-FABP) in post-acute myocardial infarction (post-AMI) patients. Methods and Results: A total of 1,283 post-AMI patients with available serum samples collected in the convalescent stage were studied. During a median follow-up period of 1,785 days, 176 patients (14%) had adverse events (all-cause mortality, n=81; non-fatal MI, n=44; readmission for heart failure [HF], n=51). Patients were divided into 2 groups according to a serum H-FABP level of 6.08 ng/ml, which was determined to be the optimal cut-off for discriminating all-cause mortality based on the maximum value of the area under the receiver operating characteristic curve. Patients with elevated H-FABP (>6.08 ng/ml, n=224) had a significantly higher incidence of death (18.3% vs. 3.8%, P<0.001) and readmission for HF (10.3% vs. 2.6%, P<0.001), but not of non-fatal MI (4.5% vs. 3.2%, P=0.187), compared to those with H-FABP <6.08 ng/ml. Multivariate Cox regression analysis indicated that elevated serum H-FABP was associated with an increased risk of mortality (hazard ratio [HR], 1.91; 95% confidence interval [CI]: 1.03-3.51, P=0.039) and readmission for HF (HR, 2.49; 95% CI: 1.15-5.39, P=0.020). Conclusions: Elevated serum H-FABP during the convalescent stage of AMI predicted long-term mortality and readmission for HF after survival discharge in the post-AMI patients.