B-type natriuretic peptide as a predictor of ischemia/reperfusion injury immediately after myocardial reperfusion in patients with ST-segment elevation acute myocardial infarction

Background:In animal models of acute myocardial infarction (AMI), B-type natriuretic peptide (BNP) administered before and during coronary occlusion limits infarct size. However, the relation between plasma BNP levels and ischemia/reperfusion injury remains unclear.Methods:302 patients with ST-segment elevation AMI (STEMI) received emergency percutaneous coronary intervention within six hours from the onset. The patients were divided into two groups according to the plasma BNP level before angiography: group L (n=151), BNP ≤32.2 pg/ml; group H (n=151), BNP >32.2 pg/ml. The Selvester QRS-scoring system was used to estimate infarct size.Results:The rate of ischemia/reperfusion injury immediately after reperfusion, defined as reperfusion ventricular arrhythmias (26% vs. 11%, p=0.001) and ST-segment re-elevation (44% vs. 22%, p=0.008), was higher in group L than in group H. Group L had a greater increase in the QRS score during percutaneous coronary intervention (3.55±0.17 vs. 2.09±0.17, p<0.001) and a higher...