Very Late Stent Thrombosis and Late Target Lesion Revascularization

Abstract

Randomized trials and registries have clearly demonstrated that drug-eluting stents (DES) are effective in reducing restenosis.1,2 After their introduction and an initial period of unbridled enthusiasm, it was recognized that there was a significant increase in very late stent thrombosis (VLST) compared with bare metal stents, and this late complication has been the subject of continued concern and intensive investigation. Very late ST is fortunately infrequent, but it is associated with very high rates of death and myocardial infarction. Understanding the frequency, duration, and potential mechanisms of VSLT has been hampered by the lack of large studies where low-frequency events can be more accurately determined and evaluated. Randomized trials, typically evaluating low-risk patients, have shown a low rate of VLST averaging 0.2%/y, but rates in registries with off-label use are higher, averaging 0.6%/y.2,3 Some studies have suggested a plateau after 3 years whereas others have not.4 Because of the selective nature of these trials, the incidence and time course in an unrestricted population is unclear. Article see p 584 In this issue of Circulation , Kimura and colleagues report on the outcome of 12 812 patients receiving the first generation sirolimus-eluting stent. In this large unrestricted registry from Japan, the cumulative incidence of definite ST was low (0.3% early, 0.6% late, and 1.6% at 5 years).5 Most disturbing, however, was the observation of the continued steady rate of VLST of 0.26%/y without any evidence of a plateau up to 5 years. The rate of VLST is consistent with other large registries with long follow-up (the Table) and is compatible with the smaller Drug-Eluting Stents in the Real World-LATE (DESIRE-LATE) study, the only other registry to have 5-year data.3, …