Association of Clopidogrel Therapy and Stent Thrombosis

Correlation of Clopidogrel Therapy Discontinuation in REAL-world Patients Treated With Drug-Eluting Stent Implantation and Late Coronary Arterial Thrombotic Events

The purpose of REAL-LATE (Correlation of Clopidogrel Therapy Discontinuation in REAL-world Patients Treated with Drug-Eluting Stent Implantation and Late Coronary Arterial Thrombotic Events) trial is to assess the relationship between clopidogrel use and long-term rates of cardiac death or MI after DES implantation in real-world practice and to estimate the duration of dual antiplatelet therapy for preventing the late thrombotic events.

An observational analysis from BASKET-LATE (Basel Stent Kosten-Effekivitats Trial-Late Thrombotic Events) examined the incidence of clinical events after cessation of clopidogrel therapy. This study identified 746 patients who were without major adverse events 6 months after drug-eluting or bare-metal stent placement. All patients had stopped taking clopidogrel and were followed up for an additional 12 months. At 18-month follow-up, there was no difference between patients with a drug-eluting or bare-metal stent in cumulative rates of death or myocardial infarction (MI). However, after clopidogrel discontinuation patients receiving drug-eluting vs bare-metal stents experienced higher rates of death and MI (4.9% vs 1.3%, respectively). These results have created uncertainty regarding the minimal necessary duration of antiplatelet therapy after drug-eluting stent implantation. Also, there remains widespread uncertainty regarding the risk of clinical events after the discontinuation of clopidogrel, particularly after DES implantation.

Inclusion Criteria:

1. Among consecutive patients treated with DES, event-free patients who survived at least the first 12 months without nonfatal MI or repeat revascularization
2. The patient or guardian agrees to the study protocol and the schedule of clinical follow-up, and provides informed, written consent, as approved by the appropriate Institutional Review Board/Ethical Committee of the respective clinical site.

Exclusion Criteria:

1. Contraindication to antiplatelet therapy (aspirin or clopidogrel)
2. Non-cardiac co-morbid conditions are present with life expectancy <1 year or that may result in protocol non-compliance (per site investigator's medical judgment).
3. Patients who are actively participating in another drug or device investigational study, which have not completed the primary endpoint follow-up period.
4. Concurrent bleeding diathesis or major bleeding history requiring discontinuation of antiplatelet drugs.
5. Patients with left main stem stenosis (>50% by visual estimate) or left main stenting
6. Concomitant disease requiring long-term use of clopidogrel (stroke, peripheral vascular disease, significant carotid a. disease, etc)