Background: There is a scarcity of long-term data from large-scale drug-eluting stent registries with a large enough sample to evaluate low-frequency events such as stent thrombosis (ST).
Methods and results: Five-year outcomes were evaluated in 12 812 consecutive patients undergoing sirolimus-eluting stent (SES) implantation in the j-Cypher registry. Cumulative incidence of definite ST was low (30 day, 0.3%; 1 year, 0.6%; and 5 years, 1.6%). However, late and very late ST continued to occur without attenuation up to 5 years after sirolimus-eluting stent implantation (0.26%/y). Cumulative incidence of target lesion revascularization within the first year was low (7.3%). However, late target lesion revascularization beyond 1 year also continued to occur without attenuation up to 5 years (2.2%/y). Independent risk factors of ST were completely different according to the timing of ST onset, suggesting the presence of different pathophysiological mechanisms of ST according to the timing of ST onset: acute coronary syndrome and target of proximal left anterior descending coronary artery for early ST; side-branch stenting, diabetes mellitus, and end-stage renal disease with or without hemodialysis for late ST; and current smoking and total stent length >28 mm for very late ST. Independent risk factors of late target lesion revascularization beyond 1 year were generally similar to those risk factors identified for early target lesion revascularization.
Conclusion: Late adverse events such as very late ST and late target lesion revascularization are continuous hazards, lasting at least up to 5 years after implantation of the first-generation drug-eluting stents (sirolimus-eluting stents), which should be the targets for developing improved coronary stents.