Effect of chronic pretreatment with beta-blockers on no-reflow phenomenon in diabetic patients with acute ST-elevation myocardial infarction undergoing primary percutaneous coronary intervention

BACKGROUND: No-reflow is an important factor as it predicts a poor outcome in patients undergoing primary angioplasty. In comparison with patients attaining TIMI 3 flow, patients with no-reflow have an increased incidence of ventricular arrhythmias, early congestive cardiac failure, cardiac rupture and cardiac death. As such, it is of paramount importance to consider strategies to prevent the occurrence of no-reflow phenomenon. Previous evidence suggests that Beta (β) blockers have multiple favorable effects on the vascular system not directly related to their effect on blood pressure. However, there are insufficient data regarding the effects of prior Beta blocker use on coronary blood flow after primary PCI in patients with AMI. AIM: The aim of this study was to test the hypothesis that Beta blocker treatment before admission would have beneficial effects on the development of the no-reflow phenomenon after acute myocardial infarction. METHODS AND RESULTS: The study included 107 diabetic patients who had presented with acute STEMI within 12 h from the onset of chest pain. All of them have undergone primary angioplasty at Ain Shams University hospitals or National Heart institute. The incidence of no-reflow phenomenon was 21%. No-reflow phenomenon was significantly lower in patients on chronic B-blocker therapy (12% vs. 28%; P = 0.04). The heart rate was significantly lower in the normal reflow group than in the no-reflow group (P = 0.03). The study also showed that B-blocker pretreatment is an independent protective predictor for the no-reflow phenomenon (P = 0.045). CONCLUSION: Chronic pre-treatment with B-blocker in diabetic patients presenting with STEMI, is associated with lower rate of occurrence of no-reflow phenomenon after primary PCI.