Comparison of Clopidogrel-based Antiplatelet Agent Treatment and Aspirin Plus Low Dose Rivaroxaban Therapy (OACART)

Rupture of atherosclerotic plaques and resulting thrombotic or embolic events can lead to myocardial infarction, stroke, and death. Particularly after vascular interventions such as percutaneous coronary intervention, stent implantation, or peripheral vascular interventions, it takes more than a year for the damaged endothelial cells to heal completely, leading to frequent thrombotic complications. In addition, clinically undiagnosed atrial fibrillation, stroke caused by thrombosis formation due to venous damage, myocardial infarction, deep vein thrombosis, and pulmonary embolism may occur. Therefore, drug therapy to prevent thrombosis is necessary for these patients, and many studies have been conducted to determine the optimal treatment.

Dual antiplatelet therapy (DAPT) with aspirin and clopidogrel is essential for treating patients after percutaneous coronary intervention (PCI). DAPT can minimize ischemic events not only in stent lesions but also in non-reperfused lesions of the coronary artery. However, DAPT increases the risk of bleeding, so a treatment strategy is needed to minimize ischemic events while reducing the risk of bleeding by using dual antiplatelet therapy for a short time after the procedure, administering antiplatelet drugs differently depending on the bleeding risk. In particular, in patients at high risk of bleeding (HBR), the side effects of bleeding due to long-term antiplatelet therapy are closely related to long-term survival, making this issue even more important. Compared to traditional aspirin use, the use of clopidogrel has been reported to reduce mortality, myocardial infarction, stroke, and hospitalization due to acute coronary artery disease while reducing bleeding complications.

In addition, a study has reported that combining low-dose anticoagulants with aspirin as a thromboprophylactic agent for stable atherosclerotic patients who were previously treated only with antiplatelet drugs reduces mortality and has superior effects on the prevention of myocardial infarction and stroke compared to aspirin alone. Aspirin and low-dose rivaroxaban combination therapy has been approved for use in patients with multivessel CAD who are over 65 years of age and have experienced acute myocardial infarction for more than one year, as well as patients with peripheral arterial disease (PAD) (history of PTA or bypass, history of foot/leg amputation, intermittent claudication with ABI <0.9, or over 50% stenosis in peripheral arteries, or over 50% stenosis in coronary arteries or previous coronary stent implantation) who have one of the two conditions: a history of acute myocardial infarction for over one year or multivessel CAD.

Ultimately, studies comparing clopidogrel and low-dose rivaroxaban and aspirin combination therapy in similar patient populations have shown the superiority of each treatment strategy, but no studies have compared the two treatment strategies. If clopidogrel monotherapy is more convenient to take, has better compliance, and is not less effective than low-dose rivaroxaban and aspirin combination therapy, it may be considered as a more convenient treatment strategy for many patients.