Long-term Outcomes of Clopidogrel Monotherapy versus Prolonged Dual Antiplatelet Therapy beyond 12 Months after Percutaneous Coronary Intervention in High-risk Patients

BACKGROUND: There are no data on comparison between clopidogrel monotherapy and prolonged dual antiplatelet therapy (DAPT) in patients at high-risk undergoing percutaneous coronary intervention (PCI). METHODS: Of 2,082 consecutive patients undergoing PCI using second-generation drug-eluting stent (DES), we studied 637 patients at high-risk either angiographically or clinically who received clopidogrel longer than 24 months and were event-free at 12 months after index PCI. Patients were divided into 2 groups: the clopidogrel monotherapy group and the prolonged DAPT group. The primary outcome was a composite of all-cause death, non-fatal myocardial infarction (MI), definite or probable stent thrombosis, or stroke between 12 months and 36 months after the index PCI. RESULTS: In propensity score-matched population (246 pairs), the cumulative rate of primary outcome was 4.5% in the clopidogrel monotherapy group and 4.9% in the prolonged DAPT group (hazard ratio, 1.21; 95% confidence interval, 0.54-2.75; P = 0.643). There was no significant difference in all-cause death, MI, stent thrombosis, stroke between the clopidogrel monotherapy group and the prolonged DAPT group. CONCLUSION: Compared with prolonged DAPT, clopidogrel monotherapy showed similar long-term outcomes in patients at high-risk after second-generation DES implantation.