Abstract 4485: Clinical, Procedural and Angiographic Predictors of Stent Thrombosis Following Drug-Eluting Stent Implantation in Unselected Patients from the Real-World Clinical Practice with Clinical Follow-up (FU) up to 6 Years

DES has demonstrated marked efficacy on reducing restenosis, and therefore TLR, in previous randomized clinical trials compared to bare metal stents. Thus, a widespread use of DES has been observed since their introduction into clinical practice, including treatment of high-risk subgroups. However, recent studies including pts from the “real-world” have raised questions regarding the long-term safety of DES, especially in more complex subsets. Between May/02-Jan/08, 2,365 unselected pts all comers for PCI with DES were prospective enrolled in this single center study. Lesion criteria included ≥1 lesion ≥50% stenosis. Clinical FU was assigned at 1, 6 and 12 months, and yearly up to 6 years (median time: 3.6 yrs). Stent thrombosis (ST) was defined according to the Academic Research Consortium. Overall, 29% of pts had diabetes, 60% multivessel disease, 40% presented with ACS (including 15% AMI). LAD was treated in 43%; 67% of lesions had complex morphology (type B2/C), including 29% mod./severe calcification, 32% eccentric, 5% ostial lesion location, and 5% in-stent restenosis. A total of 3,634 DES were implanted, and 40% had multiple stenting procedure. At late FU (98.3%), overall ST rate was 1.6% (N=38); of that, 61% were definitive (angiographic confirmation), 42% occurred between 1–12 months (late ST), and a fatal event was reported in 47%. By multivariate analysis, ST was associated to: current smoking (HR 2.59; 95%CI 1.18 –5.67; P=0.018), PCI in AMI (HR 3.50; 95%CI 1.31–9.40; P=0.013), multiple steting procedure (HR 1.81; 95%CI 1.09 –3.02; P=0.023), lesion postdilatation (HR 0.50; 95%CI 0.29 – 0.90; P=0.020), eccentric morphology (HR 1.86; 95%CI 1.03–3.34; P=0.039), mod./severe calcium (HR 2.38; 95%CI 1.34 – 4.23; P=0.003), and final residual stenosis by QCA (HR 1.04 per % unit increase; 95%CI 1.01–1.06; P=0.003). In this study, the cumulative incidence of ST up to 6 years clinical FU was very low (1.6%); however, it was associated with a fatal event in half of cases. In this analysis, ST occurred mostly between 1–12 months, and was associated with current smoking, PCI in AMI, multiple stenting, postdilatation, complex lesion morphology including eccentric and significant calcium, and stent underexpansion.