Stent-Related Cardiac Events Beyond Three Years After Implantation of the Sirolimus-Eluting Stent (from the EVASTENT Patients)

Abstract

The frequency of very late stent thrombosis (VLST) up to 3 years after sirolimus-eluting stent implantation is 0.5% to 0.6%/year but incertitude remains about the frequency of VLAST after 3 years. Diabetic (db+) and nondiabetic (db-) patients with or without multiple diseased vessels included in the EVASTENT matched-cohort registry were followed up to 6 years after stent implantation. Long-term follow-up was obtained for 1,564 of the 1,731 included patients. All-cause deaths (including cancer and complications of diabetes) occurred at steady rates of 2.5%/year up to 3 years and 1.2%/year after 3 years (difference not significant). In contrast, VLST (any Academic Research Consortium definition) was only 0.18%/year (95% confidence interval 0.08 to 0.39) after 3 years versus 0.63%/year (confidence interval 0.41 to 0.98) from 1 year to 3 years (p = 0.03). Target lesion revascularization rates were also lower after 3 years than before 3 years (1.9% vs 7%, p ≤ 0.01) with 66% of revascularization procedures after 3 years being for nontarget lesions. Six-year all-cause death and cardiac death cumulative rates were higher in db+ than in db- patients. However, after 3 years compared to before 3 years, no differences between db+ and db- patients were observed for target lesion revascularization and ST rates. It is noteworthy that 51% of patients continued to be on clopidogrel therapy nearly 6 years after receiving ≥ 1 sirolimus-eluting stent. In conclusion, all-cause deaths continued at a steady rate over 6 years. However, cardiac deaths and "very" VLST leveled out beyond 3 years.