The Predictors of No-Reflow Phenomenon after Primary Angioplasty for Acute Myocardial Infarction

Background:
No-reflow phenomenon is a serious complication of primary Percutaneous Coronary Intervention (PCI), which may increase the risk of progressive myocardial damage, profound left ventricular dysfunction, and death.
Objectives:
This study aimed to investigate the incidence of no-reflow phenomenon and its clinical, para-clinical, and angiographic determinants in patients who underwent primary PCI for ST Elevation Myocardial Infarction (STEMI).
Patients and Methods:
This non-randomized prospective cohort study was conducted on 397 patients in a cardiovascular tertiary care center in Tehran, Iran from April 2012 to April 2014. The inclusion criteria of the study were presenting with acute STEMI of ≤ 12 h duration or having admitted between 12 and 24 hours after onset with symptoms and signs of ongoing ischemia. The participants underwent standard coronary angiography. No-reflow phenomenon was defined as a Thrombolysis In Myocardial Infarction (TIMI) flow ≤ 2 and no presence of spasm, distal embolization, or dissection after completion of the procedure. The association between no-reflow and its determinants was assessed by chi-square, student’s t-test, or Mann–Whitney U test. Logistic regression models were also used for multivariate analysis. P values < 0.05 were considered to be statistically significant.
Results:
The participants’ mean (SD) age was of 59 (12.2) years and female/male ratio was 83/314. The incidence of no-reflow phenomenon was 63 (15.9%). Besides, the results of multivariate analysis showed that only thrombus burden, lesion length, time to reperfusion, and type of occlusion had an adjusted association with this phenomenon. 
Conclusions:
The study results suggested that no-reflow phenomenon after primary PCI would be predictable. Thus, preventive measures, such as using distal protective devices or administration of platelet glycoprotein IIb/IIIa antagonists, are advised to be used in high-risk patients.