Evaluation of clinical and procedural predictors of the no-reflow phenomenon in patients with acute myocardial infarction after primary percutaneous coronary intervention

Abstract

Objective To find out possible risk factors for no-reflow (NR) phenomenon in patients with acute myocardial infarction (AMI) after primary percutaneous coronary intervention (PCI).Methods A total of 312 consecutive patients with acute myocardial infarction were enrolled from January 2008 to December 2010 at the Cardiology Departmemt of East Hospital,Tongji University School of Medicine in this study.Inclusion criteria were:(1) patients underwent successful primary PCI within 12 h of symptom onset;or (2) patients with ischemic chest pain continuing for more than 12 h underwent successful primary PCI within 24 h of symptom onset.Exculsion criteria were:(1) coronary atery spasm; (2) diameter stenosis of the culprit lesion was ≤50％ and coronary blood flow was normal; (3) patients with severe left main coronary or multivessel disease,who had to require emergency surgical revascularization.According to thrombolysis in myocardial infarction (TIMI) flow grade,the patients were divided into reflow group and NR group.The clinical date,angiography findings and surgical date were compared between two groups.Univariate and multivariate logistic regression were used to determine the predictors for NR phenomenon.Results Sixtyone (20.3％) of the patients developed NR phenomenon after primary PCI.Univariate analysis showed that patients' age,time from onset to reperfusion,systolic blood pressure (SBP) on admission,Killip class of myocardial infarction,intra-aortic balloon pump (IABP) use before primary PCI,TIMI flow grade before primary PCI,type of occlusion,thrombus burden on baseline angiography,target lesion length,reference luminal diameter and method of repusion were correlated with NR phenomenon (P＜ 0.05 for all).Multiple logistic regression analysis identified that age ＞ 65 years (OR =1.470,95％ CI 1.460-1.490,P =0.007),long time from onset to reperfusion ＞6 hours (OR =1.270,95％ CI 1.160-1.400,P =0.001),low SBP on admission ＜100mmHg (1 mmHg=0.133 kPa) (OR=1.910,95％ CI 1.018-3.896,P =0.004),IABP use before PCI (OR =1.949,95％ CI 1.168-3.253,P =0.011),low (≤1) TIMI flow grade before primary PCI (OR =1.100,95％ CI 1.080-1.250,P ＜ 0.01),high thrombus burden (OR =1.600,95％ CI 1.470-2.760,P =0.030) and long target lesion (OR =1.948,95％ CI 1.908-1.990,P =0.019) on angiography as independent predictors of NR phenomenon.ConclusionsThe occurrence of NR phenomenon after primary PCI for acute myocardial infarction can be predicted using simple clinical,angiographic and procedural features. Key words: Acute myocardial infarction ; No-reflow phenomenon; Percutaneous coronary intervention ; Thrombus