Abstract 2827: Relationship of Occurrence of Drug-Eluting Stent Thrombosis and Assumption of Double Antiplatelet Therapy
Background- Several studies have identified lack of clopidogrel therapy as one of the most significant predictors of stent thrombosis (ST) after drug-eluting stent implantation (DES). In clinical trials double antiplatelet therapy has been adopted for 3–6 months. However, it is still unclear if longer periods of double antiplatelet regimen may reduce the incidence of ST. We report the incidence of ST according to the time of occurrence and the assumption of antiplatelet therapy.
Methods and Results- We have analyzed 2160 consecutive patients that underwent DES implantation between April 2002 and December 2004. The events, according to the antiplatelet treatment and the time of occurrence are reported in table⇓. ST was defined by angiographic or autopsy documentation (stent complete or partial occlusion in the setting of acute coronary syndrome) or target vessel related myocardial infarction. The incidence of ST was higher in the first semester among patients who discontinued antiplatelets. After one-year follow-up ST rate did not differ between patients on double antiplatelet therapy versus patients assuming only aspirin (p=0.31).
Conclusions- The discontinuation of antiplatelet therapy during the first 6-months increases the incidence of ST following DES implantation. Our results do not support the need of prolonged dual antiplatelet therapy in the unselected population beyond 6–12 month.