Antiplatelet Therapy In Elderly ACS Patients With High Ischemic And Bleeding Risk After 12 Months DAPT Following New-Generation DES

Objective:To evaluate the safety and efficacy of 12-month dual antiplatelet therapy(DAPT)followed by clopidogrel versus DAPT continuation for 9 months in elderly acute coronary syndrome(ACS)patients with high risk of ischemia and bleeding undergoing percutaneous coronary intervention(PCI)with new-generation drug-eluting stent(DES),and provide new clinical evidence for DAPT strategy in elderly ACS patients after PCI with new-generation DES.Methods:This study was a single-center,randomized controlled clinical trial.The elderly ACS patients(?65 years old)with high ischemic and bleeding risk after 12 months DAPT following new-generation DES admitted to the department of geriatric cardiology in Sichuan provincial people's hospital were enrolled from January 2018 to June 2019.The included patients were randomly divided into two groups,the clopidogrel group and DAPT continuation group.The DAPT continuation group,consisting of aspirin(100mg/d)and clopidogrel(75mg/d),was compared to clopidogrel group(75mg/d).The routine medications such as statins and beta-blockers were administered in all enrolled patients.The clinically related events in the two groups were observed and recorded within 9-month follow-up.The primary outcome was the incidence of bleeding events.The secondary outcome included the time of first bleeding event and incidence of major adverse cardiovascular and cerebrovascular events(MACCE).MACCE was defined as the occurrenc of death,non-fatal myocardial infarction,stroke,targetlesion revascularization and unstable angina during follow-up.Results:1.In this study,a total of 154 elderly ACS patients(?65 years old)after 12 month DAPT following new-generation DES were enrolled,72 patients in clopidogrel group and82 patients in DAPT continuation group.There was no significant difference in baseline clinical characteristics,coronary artery lesion characteristics and PCI data between the two groups(P>0.05).2.At 9-month follow-up,bleeding events occurred in 7 patients(9.7%)in clopidogrel group,1 patients(1.4%)with major bleeding and 6(8.3%)with minor bleeding.Minor bleeding events occurred in 19 patients(23.2%)in DAPT continuation group,without major bleeding events.There was no significant difference in the incidence of major bleeding events between the two groups(P=0.468).The incidence of minor and total bleeding events in clopidogrel group was significantly lower than that in DAPT continuation group(P=0.013 and P=0.026).None patients changed antiplatelet strategies due to bleeding.3.The time of the first bleeding event in DAPT continuation group was significantly earlier,compared with clopidogrel group(P<0.001).4.A 9-month follow-up,the incidence of major adverse cardiac and cerebrovascular event(MACCE)in clopidogrel group and DAPT continuation group was11.1% and 6.1%,respectively.There was no significant difference(P=0.264).Conclusion:By comparing clopidogrel monotherapy with DAPT continuation for 9 months in elderly ACS patients with high risk of ischemia and bleeding after 12 months DAPT following new-generation DES,we came to the conclusion:1.Clopidogrel monotherapy reduced the incidence of minor and total bleeding events,compared with DAPT continuation.2.The time of the first bleeding event in DAPT continuation group occurred significantly earlier.3.The effect of clopidogrel monotherapy on ischemic events was not inferior to that of DAPT continuation.