Comparison of clinical outcomes in patients with 4b acute myocardial infarction caused by early and late stent thrombosis / 天津医药

ABSTRACT

Objective To observe and compare in-hospital and 1-year survival and prognosis of patients with 4b acute myocardial infarction(AMI)caused by early and late stent thrombosis(ST).Methods A total of 302 patients with 4b acute myocardial infarction caused by ST were enrolled in this study from January 2015 to February 2018.ST patients were confirmed by coronary angiography.These patients were divided into two groupsthe early ST group(n=26)and the late ST group(n=276)according to the time of ST occurrence.Endpoint events during hospitalization and one year of follow up were compared between the two groups of patients.The primary endpoint events included cardiac death and recurrent AMI.The secondary endpoint events included target lesion revascularization(TLR),re-stent thrombosis,heart failure and stroke.The incidence of no endpoint events was compared between two groups of patients by Kaplan and Meier survival analysis.Cox regression analysis was used to analyze risk factors for endpoint events in patients with type 4b AMI.Results There was no significant difference in the incidence of the primary endpoint events during hospitalization between the two groups(7.7%vs.3.3%,P=0.243).The incidence of heart failure was higher in the early ST group than that of the late ST group(11.5%vs.1.4%,P=0.016).There was no significant difference in the incidence rates of other secondary endpoint events between the two groups(P＞0.05).After a mean follow-up of 1 year,the incidence rates of primary endpoint events and the secondary eendpoint events were higher in the early ST group(20.0%vs.5.9%,P＜0.05 and 36.0%vs.11.5%,P＜0.01)than that of the late ST group.Kaplan and Meier survival analysis showed that the 1-year cumulative incidences of non-primary(P= 0.022)and non-secondary events(P＜0.001)were lower in the early ST group than those of the late ST group.Cox regression analysis showed that hypertension and history of coronary artery bypass grafting were independent risk factors for primary endpoint events in patients with 4b AMI,and intraoperative implantation of intraaortic balloon pump(IABP)and shortening the time from stent thrombosis to balloon dilation(ST to B)were independent protective factor.Conclusion Early ST patients have similar in-hospital outcomes and poor long-term prognosis compared with late ST induced 4b type AMI patients.Intraoperative implantation of IABP and shortening of ST to B time may improve the prognosis of 4b type AMI patients.