Characteristics of Infarct-Related Artery in Different Patterns of Acute Myocardial Infarction

Objective:To investigate the characteristics of infarct-related artery (IRA)in patients with acute myocardial infarction with electrocardiogram (ECG) showing ST-segment elevation (STEMI) or non-ST-segment elevation(NSTEMI). Methods:From December 2003 to September 2006,the patients who had confirmed diagnosis of acute myocardial infarction and experienced emergency angiography within 24 hours from the heart attack were enrolled.Among them, the artery lesion characteristics of the 42 patients with STEMI whose angiography showing non-total occlusion of IRA were compared with those of the 16 patients with NSTEMI whose angiography showing total occlusion of IRA. Results:①All the IRAs of STEMI cases were main arteries;While in NSTEMI group, there were 6 patients (37.5%) with IRAs not main arteries. There were more lesions located in proximal or medial position of main arteries in STEMI group than in NSTEMI group[38(90.5%) vs 7(43.8%),P0.05].②The patients in NSTEMI group had more collateral branches to IRAs than those in STEMI group[10 (62.5%)vs 10(23.8%) P0.05 ]. Conclusion: There were more patients with IRA lesions locating in main coronary arteries,proximal or medial position,but less collateral branches in STEMI group than in NSTEMI group.