Dynamic changes of brain natriuretic peptide concentration and its diagnostic value for heart failure in early phase of acute myocardial infarction

OBJECTIVE To explore the dynamic changes in brain natriuretic peptide (BNP) concentration and the diagnostic value of BNP for heart failure at different time points in the early phase of acute myocardial infarction (AMI). METHODS AMI patients who were admitted in our department between January 1, 2016 and July 31, 2016 and underwent emergency percutaneous coronary intervention (PCI) within 12 h after onset were enrolled in this study. All the patients received bedside examinations of BNP concentration and clinical cardiac function within 1 h after PCI and at 12, 20, 24 and 48 h after the onset of AMI. According to the peak BNP concentration, the patients were divided into high peak BNP group (> 400 pg/mL) and normal peak BNP group (≤400 pg/mL). RESULTS Seventy patients were enrolled in the study. Within 48 h after AMI onset, BNP concentration variations followed a pattern of an initial increase till reaching the peak concentration at 20 to 24 h, with subsequent gradual decrease. BNP concentrations differed significantly among the indicated time points (χ2=141.7, P 0.05). Compared with those in normal peak BNP group, the patients in high peak BNP group had an older age, a lower BMI, a longer time to perfusion, and a higher likeliness of anterior myocardial infarction and pulmonary infection (P 0.05), while BNP concentrations at 12, 20, 24 and 48 h after AMI onset had significant diagnostic values for heart failure (P < 0.05) with areas under ROC of 0.860, 0.786, 0.768 and 0.863, and optimal cutoff values of 156.5, 313.7, 240.9 and 285.9 pg/mL, respectively. CONCLUSIONS BNP concentration increases first and then decreases in the early phase of AMI, and the peak concentration occurs at 20-24 h after the onset. The diagnostic values of BNP concentrations at different time points also vary.