Predictors of interruption of antiplatelet therapy after DES

Predictors of interruption of antiplatelet therapy after DES

Predictors of interruption of antiplatelet therapy after DES: Discontinuation of antiplatelet therapy may lead to the catastrophic situation of stent thrombosis in those who have undergone percutaneous coronary interventions (PCI). The risk is more in those who have undergone PCI with implantation of drug eluting stents (DES). This is thought to be due to the delayed endothelialization after implantation of DES due to the therapeutic effect of the drug which was originally meant to reduce neointimal proliferation and consequent restenosis of the vessel. Though DES reduces the incidence of restenosis compared to bare metal stents, the nightmare of potential delayed stent thrombosis prevails. It is in this context that a recent study (Circulation. 2010;122:1017-1025) evaluated the interruptions to antiplatelet therapy in the first year after implantation of a DES, which is thought to carry a significant risk of stent thrombosis. About fourteen percent of patients interrupted at least one antiplatelet drug, most often clopidogrel. The withdrawal was due to either bleeding events or invasive procedures in nearly half of them. The predictors of interruption of antiplatelet therapy were renal impairment, history of prior major hemorrhage and peripheral arterial disease. The interruption was by a medical decision in 70 of the 234 instances and one the predictor for this situation was long term use of anticoagulant therapy. It is noteworthy that thirty nine patients interrupted the anti platelet therapy on their own, some of whom were consumers of psychotropic drugs. The authors conclude that interruption of antiplatelet therapy in the first year after implantation of a DES was partly based on patient decision or a medical decision not associated with major bleeding events or major surgical procedures.