Detection Of Coronary Microcirculation Resistance Index(IMR) To Investigate The Effect Of Nicorandil On Coronary Microcirculation In NSTEMI Patients After PCI

Objective: Acute myocardial infarction was one of the important causes of death in patients with coronary heart disease.And non-ST-segment elevation myocardial infarction(NSTEMI)patients were more and more,also younger and younger.The incidence of multiple vascular disease was high in NSTEMI patients,and the incidence of angina pectoris or secondary reinfarction was also high.Compared with patients with ST-elevation myocardial infarction(STEMI),the long-term prognosis of patients with NSTEMI was worse.However,percutaneous coronary intervention(PCI)had been done,they also faced with the problem of microcirculation.The research about protection and improvement of coronary microcirculation function after PCI had gradually attracted the attention of cardiovascular experts and scholars.Nicorandil had a nitric acid ester and a unique dual potassium channel opening effect,which could expand the coronary artery,especially coronary microcirculation,to protect myocardial.This study was conducted by examining what was considered to be the most sensitive and accurate index about assessment of the degree of coronary microcirculation impairment: Index of Microcirculatory Resistance(IMR),to explored postoperative coronary microcirculation influence of patients with NSTEMI after oral administration of nicorandil 3 days before their PCI.Methods: A total of 40 patients with non-ST-segment elevation myocardial infarction who were from 18 to 80 years old were enrolled in the study from January to August 2016 in the Department of Cardiology,the Central Hospital of Xiangtan City,and they had to accept elective PCI.They all had Coronary Angiography(CAG)examination been done.According to the randomized control principle,all of them were divided into two groups: nicorandil group(n = 20)and control group(n = 20).Patients in the nicorandil group were treated with nicorandil(5 mg TID)and conventional optimal drug therapy;in the control group,patients were treated with conventional optimized medications and without nicorandil.Two groups of patients planned to detect IMR after PCI,and then baseline clinical data,intraoperative data,postoperative IMR values and other indicators were compared.Results: 1.There were no significant differences of the clinical characteristics(such as age,sex,diabetes,hypertension,etc.)between the two groups.2.The IMR value of the nicorandil group were much lower than that of the control group(18.65±6.06 U VS 26.60±11.61 U,P=0.01).There was significant difference.3.In this study,nicorandil reduced postoperative cTNT and CK-MB level compared with control group.Conclusions: Preoperative administration of nicorandil had a protective effect on coronary microcirculation in patients with NSTEMI.