Preliminary observations regarding angiographic pattern of restenosis after rapamycin-eluting stent implantation

Background - Restenosis after implantation of drug-eluting stents ( DES) is a rare phenomenon, occurring more frequently peri-stent. Methods and Results - We evaluated the pattern of restenosis occurring after implantation of DES in unselected lesions. From April 15 to December 6, 2002, we treated 368 patients with 735 lesions by using 841 rapamycin-eluting stents ( Cypher, Cordis, a Johnson & Johnson Company). Mean baseline lesion length was 17.48 +/- 12.19 mm, and mean stent length was 27.59 +/- 14.02 mm. Follow-up ischemia-driven angiography was performed in 24 patients. Eleven patients had angiographic restenosis (greater than or equal to 50% diameter stenosis) in 14 stented segments ( stent and 5 mm proximal and distal to the stent). The pattern of restenosis in all 14 stented segments was focal, and in 6 of them it was multifocal, occurring inside the stents. Mean length of restenotic lesions was 5.62 +/- 1.90 mm, with a range from 2.54 to 8.44 mm. One multifocal restenosis involved also the distal stent margin. Intravascular ultrasound evaluation at follow-up, performed in 2 patients, showed significant lumen obstruction attributable to in-stent hyperplasia in both cases. Individual cases can be viewed in the Data Supplement. Conclusions - The pattern of restenotic lesions after rapamycin-eluting stent implantation was focal and mostly inside the stent.