Korean Circ J.  2020 Feb;50(2):120-129. 10.4070/kcj.2019.0166.

Clopidogrel versus Aspirin after Dual Antiplatelet Therapy in Acute Myocardial Infarction Patients Undergoing Drug-Eluting Stenting

• Sim DS
• Jeong MH
• Kim HS
• Gwon HC
• Seung KB
• Rha SW
• Chae SC
• Kim CJ
• Cha KS
• Park JS
• Yoon JH
• Chae JK
• Joo SJ
• Choi DJ
• Hur SH
• Seong IW
• Cho MC
• Kim DI
• Oh SK
• Ahn TH
• Hwang JY
• on behalf of the KAMIR-NIH registry investigators

• KMID: 2468037
• DOI: http://doi.org/10.4070/kcj.2019.0166

Abstract

BACKGROUND AND OBJECTIVES
There is a paucity of data regarding the benefit of clopidogrel monotherapy after dual antiplatelet therapy (DAPT) in patients treated with drug-eluting stents (DES). This study compared outcome between clopidogrel versus aspirin as monotherapy after DES for acute myocardial infarction (MI).
METHODS
From Korea Acute Myocardial Infarction Registry-National Institute of Health database, 1,819 patients treated with DES who were switched to monotherapy with clopidogrel (n=534) or aspirin (n=1,285) after uneventful 12-month DAPT were analyzed. The primary endpoint was net adverse clinical events (NACE), defined as a composite of death from any cause, MI, repeat percutaneous coronary intervention (PCI), stent thrombosis, ischemic stroke, or major bleeding during the period from 12 to 24 months.
RESULTS
After adjustment using inverse probability of treatment weighting, patients who received clopidogrel, compared with those treated with aspirin, had a similar incidence of NACE (0.7% and 0.7%; hazard ratio, 1.06; 95% confidence interval, 0.31-3.60; p=0.923). The 2 groups had similar rates of death from any cause (0.1% in each group, p=0.789), MI (0.3% and 0.1%, respectively; p=0.226), repeat PCI (0.1% and 0.3%, respectively; p=0.548), stent thrombosis (0.1% and 0%, respectively; p=0.121), major bleeding (0.2% in each group, p=0.974), and major adverse cardiovascular and cerebrovascular events (0.5% in each group, p=0.924).
CONCLUSIONS
Monotherapy with clopidogrel, compared to aspirin, after DAPT showed similar clinical outcomes in patients with acute MI treated with DES.

Keyword

Antiplatelet agents; Drug-eluting stents; Myocardial infarction

MeSH Terms

Aspirin*
Drug-Eluting Stents
Hemorrhage
Humans
Incidence
Korea
Myocardial Infarction*
Percutaneous Coronary Intervention
Platelet Aggregation Inhibitors
Stents*
Stroke
Thrombosis
Aspirin
Platelet Aggregation Inhibitors

Figure

• 

  Figure 1 The study flow diagram of the patients. AMI = acute myocardial infarction; APT = antiplatelet therapy; DAPT = dual antiplatelet therapy; DES = drug-eluting stents; KAMIR-NIH = Korea Acute Myocardial Infarction Registry-National Institute of Health; MI = myocardial infarction; OAC = oral anticoagulants.

• 

  Figure 2 IPTW-adjusted cumulative incidence of NACE during the period from 12 to 24 months according to study group. IPTW = inverse probability of treatment weighting; NACE = net adverse clinical events.

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