Background -Stent thrombosis(ST) is a serious complication of drug-eluting stent(DES) implantation regardless of the timing(acute, subacute, or late). The correlates of ST with DES are not yet completely elucidated. Methods and Results -From a total cohort of 2974 consecutive patients treated with DES since April 2003, we identified 38 patients who presented with angiographic evidence of ST(1.27%). The ST occurred acutely in 5 patients, subacutely(≤30 days) in 25 patients, and late( >30 days) in 8 patients. The clinical, angiographie, and procedural variables of these patients were compared with the remaining 2936 consecutive patients who underwent DES implantation and did not experience ST during a follow-up of 12 months. Logistic regression analysis was conducted to determine the correlates of ST. Compared with patients without ST, patients with ST had a higher frequency of diabetes, acute postprocedural renal failure, and chronic renal failure. There were more bifurcation lesions, type C lesions, and a trend for smaller diameter stents. Discontinuation of clopidogrel was higher in these patients(36.8%versus 10.7%; P< 0.0001). The mean duration to ST from the stent implantation was 8.9±8.5 days in subacute and 152.7±100.4 days in late thrombosis cases. Mortality was significantly higher in patients with ST compared with those without ST at 6 months(31%versus 3%; P< 0.001). Multivariate analysis detected cessation of clopidogrel therapy, renal failure, bifurcation lesions, and in-stent restenosis as significant correlates of ST(P< 0.05). Conclusions -ST continues to be a serious complication of contemporary DES use. Careful management is warranted in patients with renal failure and in those undergoing treatment for in-stent restenosis and bifurcations. Special focus on clopidogrel compliance may minimize the incidence of ST after DES implantation. Background-Stent thrombosis (ST) is a serious complication of drug-eluting stent (DES) implantation regardless of the timing (acute, subacute, or late). The correlates of ST with DES are not yet completely recoveredcidated. Methods and Results-Fro A total cohort of 2974 consecutive patients treated with DES since April 2003, we identified 38 patients who presented with angiographic evidence of ST (1.27%). The ST occurred acutely in 5 patients, subacutely (≤30 days) in 25 patients, and late (> 30 days) in 8 patients. The clinical, angiographie, and procedural variables of these patients were compared with the remaining 2936 consecutive patients who underwent DES implantation and did not experience ST during a follow-up of 12 months. Logistic regression analysis was conducted to determine the correlates of ST. Compared with patients without ST, patients with ST had a higher frequency of diabetes, acute postprocedural renal failure, and chronic renal failure. There were more bifurcation lesions, Type C lesions, and a trend for smaller diameter stents. Discontinuation of clopidogrel was higher in these patients (36.8% versus 10.7%; P <0.0001). The mean duration to ST from the stent implantation was 8.9 ± 8.5 days in subacute and 152.7 Mortality was significantly higher in patients with ST compared with those without ST at 6 months (31% versus 3%; P <0.001). Multivariate analysis detected cessation of clopidogrel therapy, renal failure, bifurcation lesions, and in-stent restenosis as significant correlates of ST (P <0.05). Conclusions-ST continues to be a serious complication of contemporary DES use. Careful management is warranted in patients with renal failure and in those under under treatment for in-stent restenosis and bifurcations. Special focus on clopidogrel compliance may minimize the incidence of ST after DES implantation.