Association of Clopidogrel Therapy and Stent Thrombosis

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

• Among consecutive patients treated with DES, event-free patients who survived at least the first 12 months without nonfatal MI or repeat revascularization
• 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

• Contraindication to antiplatelet therapy (aspirin or clopidogrel)
• 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).
• Patients who are actively participating in another drug or device investigational study, which have not completed the primary endpoint follow-up period.
• Concurrent bleeding diathesis or major bleeding history requiring discontinuation of antiplatelet drugs.
• Patients with left main stem stenosis (>50% by visual estimate) or left main stenting
• Concomitant disease requiring long-term use of clopidogrel (stroke, peripheral vascular disease, significant carotid a. disease, etc)