Sustained suppression of neointimal proliferation by sirolimus-eluting stents - One-year angiographic and intravascular ultrasound follow-up

Background-We have previously reported a virtual absence of neointimal hype rplasia 4 months after implantation of sirolimus-eluting stents. The aim of the present investigation was to determine whether these results are susta ined over a period of 1 year. Methods and Results-Forty-five patients with de novo coronary disease were successfully treated with the implantation of a single sirolimus-eluting Bx VELOCITY stent in Sao Paulo, Brazil (n=30, 15 fast release [group I, GI] a nd 15 slow release [GII]) and Rotterdam, The Netherlands (15 slow release, GIII). Angiographic and volumetric intravascular ultrasound (IVUS) follow-u p was obtained at 4 and 12 months (GI and GII) and 6 months (GIII). In-sten t minimal lumen diameter and percent diameter stenosis remained essentially unchanged in all groups (at 12 months, GI and GII; at 6 months, GIII). Fol low-up in-lesion minimal lumen diameter was 2.28 mm (GIII), 2.32 mm (GI), a nd 2.48 mm (GII). No patient approached the greater than or equal to 50% di ameter stenosis at I year by angiography or IVUS assessment, and no edge re stenosis was observed. Neointimal hyperplasia, as detected by IVUS, was vir tually absent at 6 months (2 +/-5% obstruction volume, GIII) and at 12 mont hs (GI=2 +/-5% and GII=2 +/-3%). Conclusions-This study demonstrates a sustained suppression of neointimal p roliferation by sirolimus-eluting Bx VELOCITY stents 1 year after implantat ion.