Incidence, risk factors, and clinical sequelae of angiographic peri-stent contrast staining after sirolimus-eluting stent implantation.

BACKGROUND: We have noted abnormal angiographic findings--at the sites of drug-eluting stent implantation, suggesting contrast staining outside the stent struts--that do not fulfill the classic definition of coronary artery aneurysm. We propose a new term, peri-stent contrast staining (PSS), for these abnormal angiographic findings and assess their incidence, risk factors, and clinical sequelae. METHODS AND RESULTS: Peri-stent contrast staining was defined as contrast staining outside the stent contour extending to ≥20% of the stent diameter. The study population consisted of 3081 lesions (1998 patients) that were treated exclusively with sirolimus-eluting stents and were evaluated by follow-up angiography within 12 months after sirolimus-eluting stent implantation in a single center. Late acquired PSS was observed in 58 lesions (1.9%) in 49 patients (2.5%). Independent risk factors of PSS included chronic total occlusion, whereas negative risk factors for PSS were left circumflex coronary artery lesion and in-stent restenosis lesion. Stent fracture was more frequently observed in lesions with PSS than in lesions without PSS (43.1% versus 5.4%, P<0.0001). Excluding 269 lesions with target-lesion revascularization within 12 months, the study population for long-term follow-up consisted of 51 lesions (42 patients) with PSS and 2761 lesions (1751 patients) without PSS. Cumulative incidence of target-lesion revascularization and definite very late stent thrombosis at 3 years in the PSS group was higher than that in the non-PSS group (15.0% versus 6.5%, and 8.2% versus 0.2%, respectively). CONCLUSIONS: Peri-stent contrast staining found within 12 months after sirolimus-eluting stent implantation appeared to be associated with subsequent target-lesion revascularization and very late stent thrombosis.