Abstract 2253: Young Age, Acute Myocardial Infarction and Complex Lesions are Major Risk Factor for Drug Eluting Stent Thrombosis in Asia
Background Drug-eluting stents (DES) have dramatically reduced the rate of restenosis. However, concerns have been raised regarding the stent thrombosis (ST) with the unrestricted use of these stents. Therefore, we investigated the clinical characteristics, predictors and clinical outcome of ST after successful DES implantation in Asian population.
Method This study comprised consecutive DES thrombosis patients who underwent stent implantation from May, 2004, through Dec, 2005 at 10 major medical centers (>700 PCI patients/year) in Korea. Whole data of DES thrombosis patients were sent to a core center and the clinical, angiographic and procedural characteristics of ST patients were compared with a control group of 1,295 patients in a core center who had upto 18 months of clinical follow-up. Possible ST(sudden death, fatal out-of-hospital cardiac arrest, or myocardial infarction (MI), not clearly attributable to another coronary lesion) as well as angiographically proven ST were defined as ST in this study.
Results During the study period, a total of 84 patients had 88 cases of ST including angiographically proved 81 cases(Cypher:48(55%), TAXUS: 40(45%)). The ST occurred acutely in 4 cases(4.5%), subacutely(≤30 days) in 48 cases(54.5%), and late(>30 days) in 36 cases(41%). The mean duration to ST from the stent implantation was 6.4±5.9 days in subacute and 333.4±228 days in late ST cases. Seven patients had discontinued antiplatelet therapy prematurely(8%). Sixty-seven(77%) of the patients presented with ST were treated with percutaneous coronary intervention and 5(6%) were treated with CABG. Among these 84 patients, 13 died (case fatality rate, 15%). Independent predictors of ST were age(OR per 1 year decrease: 1.03; 95% CI,1.01–1.06; P=0.006), acute myocardial infarction(OR 7.84; 95% CI, 4.48 –13.71;P<0.001), bifurcating lesion(OR:8.49; 95% CI, 4.81–14.98; P<0.001), preintervention reference diameter (OR per 1mm decrease: 3.32; 95% CI, 1.66 – 6.67; P<0.001), and preintervention lesion length (OR per 1mm increase: 1.04; 95% CI, 1.02–1.06; P<0.001).
Conclusions In Asian population, young age, acute myocardial infarction, bifurcating lesion, small reference diameter and long lesion length were were identified as predictors of ST.