Coronary Restenosis After Sirolimus‐Eluting Stent Implantation: Morphological Description and Mechanistic Analysis From a Consecutive Series of Cases

Background We describe the clinical and morphological patterns of restenosis after sirolimus‐eluting stent (SES) implantation. Methods and Results From 121 patients with coronary angiography obtained >30 days after SES implantation, restenosis (diameter stenosis >50%) was identified in 19 patients and 20 lesions (located at the proximal 5‐mm segment in 30% or within the stent in 70%). Residual dissection after the procedure or balloon trauma outside the stent was identified in 83% of the proximal edge lesions. Lesions within the stent were focal, and stent discontinuity was identified in some lesions evaluated by intravascular ultrasound. Conclusions Sirolimus‐eluting stent edge restenosis is frequently associated with local trauma outside the stent. In‐stent restenosis occurs as a localized lesion, commonly associated with a discontinuity in stent coverage. Local conditions instead of intrinsic drug‐resistance to sirolimus are likely to play a major role in post‐SES restenosis. (Circulation. 2003; 108:257‐260.)