Coronary artery aneurysms (CAAs) defined as angiographic luminal dilatation (50% larger than the adjacent reference vessel) at the site of stent implantation are rare and the reported incidence varies from 0.3% to 6%(Aoki et al., 2008). A new term, peri-stent contrast staining (PSS) was defined as contrast staining outside the stent contour extending to ≥20% of the stent diameter which do not fulfill the classic definition of CAAs by a Japanese group (Imai et al., 2011). It is controversial that these abnormal angiographic findings may be related with adverse clinical events because recent DES registry data showed CAAs took mostly favorable clinical courses with continuous dual-antiplatelet therapy (Ahn et al., 2010) although poor clinical outcomes including in-stent restenosis and stent thrombosis after drug-eluting stent (DES) implantation were increased with CAAs after DES implantation (James et al., 2009).
In this study to assess the clinical outcome of CAAs and PSS after percutaneous coronary intervention (PCI) under the realworld practice, the patients with CAA or PSSs were younger and non-diabetic undergoing PCI with longer DES implantation, especially Sirolimus eluting stent. Poor clinical outcomes including in-stent restenosis and targel lesion revascularization were increased in the patients with CAA/PSS than without CAA/PSS but there was no difference of cardiovascular and all-cause mortality. In the subgroup analysis, there are no events of cardiac death but stent thrombosis and myocardial infarction were developed more frequently in CAA group compared with PSS group.