Intravascular ultrasound assessment of very late bare-metal stent thrombosis: A case report

Very late stent thrombosis (VLST) is increasingly being regarded as a complication of drug-eluting stents (DES), and delayed endothelization, local hypersensitivity reactions, and late stent malapposition due to excessive positive remodeling have been postulated as mechanisms. Considering that stent endothelialization seems to be completed within 4 weeks following bare-metal stent (BMS) placement and that BMS do not possess antiproliferative coating, the mechanism of VLST may differ between patients with DES and those with BMS. We report a case of VLST 9 years after BMS implantation, in which thrombus from the ruptured neointima was confirmed by intravascular ultrasound. This finding suggests that de novo plaque rupture at the neointimal layer within the stent may be one of the explanations for VLST.