Difference in clinical and angiographic characteristics of very late stent thrombosis between drug-eluting and bare-metal stent implantations.

Background: Limited data are available with which to compare the clinical characteristics of patients with very late stent thrombosis (VLST) after drug-eluting stent (DES) or bare-metal stent (BMS) implantation. The purpose of this study was to investigate the differences in the characteristics of VLST after DES and BMS implantation by reviewing the clinical and angiographic data. Methods and Results: A total of 28 patients (30 lesions) with VLST after DES implantation and 33 patients (33 lesions) with VLST after BMS implantation were identified. The occurrence of VLST after BMS implantation (2,647 +/- 996 days) was much later than that after DES implantation (1,194 +/- 558 days, P<0.001). The number of VLST after DES implantation increased gradually each year; however VLST after BMS implantation started to occur >50 months later, and its number increased subsequently. The prevalence of VLST related to surgical procedures involving discontinuation of antiplatelet therapy in VLST patients was higher after DES implantation (14.3%) than after BMS implantation (0%, P=0.039). Angiographic stent fracture was seen in 36.7% of VLST lesions after DES implantation at different times (464-2,102 days after procedure), while none was seen in VLST lesions after BMS implantation (P<0.001). Conclusions: The timing of VLST was different after DES and BMS implantation. Stent fracture was a specific finding of VLST after DES implantation.