Case of very late stent thrombosis after discontinuation of dual antiplatelet therapy

Stent thrombosis remains the main cause of death after percutaneous coronary intervention. Stent thrombosis prevention refers to optimal stent implantation, as well as to the usage of dual anti-platelet therapy. We report a case of a very late stent thrombosis after discontinuation of dual antiplatelet therapy. The patient had a history of a previous coronary disease, he suffered from acute myocardial infarction (MI) and underwent bare metal stent (BMS) implantation in the left anterior descending artery (LAD) and also (DES) in the right coronary artery (RCA). One year later, he presented again with acute MI, but without angiography documented in stent restenosis in the RCA. He ran out of his medication. Next year he experienced an episode of chest pain and was taken to the cardiac catheterization laboratory, where he was found to have occluded distal RCA with apparent thrombus in the stented segment. The patient had discontinued clopidogrel therapy 15 days prior to this. After the initial dilatation thrombus was seen and two bare metal stents were implanted. The extended treatment by dual anti-platelet therapy after PCI (more than 12 months with patients with low bleeding risk) showed the decrease of ischemic cardiovascular developments rate, including stent thrombosis. Our patient had two episodes and both occurred one month after cessation of clopidogrel therapy. The lack of dual antiplatelet therapy according to this study is a major contributing factor when clopidogrel is discontinued after 12 months.