A case of active peri-stent inflammation after sirolimus-eluting stent implantation

We report an autopsy case of a coronary aneurysm with massive adventitial inflammation post-percutaneous coronary intervention with sirolimus-eluting stent (SES) insertion in the left circumflex (LCX) coronary artery for ischemic heart disease 3 years prior to death. The internal elastic membrane was disrupted opposite the site of the eccentric LCX plaque due to injury during stenting, and the adventitia showed massive inflammatory cell infiltration, mainly consisting of eosinophils. The LCX showed aneurysmal dilatation with inflammatory cell infiltration. Inappropriate SES implantation attracted chronic inflammation. Chronic inflammation can lead to the development of coronary artery aneurysms.