Giant Coronary Artery Aneurysm Due to Implantation of Drug-Eluting Stent

Development of coronary artery aneurysm after implantation of a drug-eluting stent is a rare complication. The mechanism behind aneurysm formation is unknown, but studies suggest hypersensitivity and inflammatory reactions elicited by the stent polymer. Here, we report a case of a 57-year-old man who was treated with a sirolimus-eluting Cypher stent in the left anterior descending artery due to stable angina pectoris and left circumflex artery due to dissection. Coronary aneurysm formation at the site of stent implantation was discovered three years after the stents were deployed, and progression of the aneurysms was seen in the coronary artery angiography. We hypothesize about the mechanism of aneurysm formation and present management of the aneurysms.