An unusual case of acute coronary syndrome late after stent implantation.

We report a case of a 66-year-old Caucasian male who presented to our department with unstable angina in July 2011. He had a medical history of trivessel coronary artery disease and underwent several percutaneous coronary interventions (2003, 2004, and 2006). The latest coronary angiography, performed in January 2011, showed mild intimal hyperplasia within the proximal left anterior descending segment, treated with a sirolimus-eluting stent in 2003. On admission, electrocardiogram was positive for a recent acute coronary syndrome, so the patient underwent coronary angiography, which showed proximal left anterior descending stent thrombosis, occurred eight years after drug-eluting stent implantation. Intravascular ultrasound revealed a soft plaque rupture within the stented segment, which was the cause of stent thrombosis. So the lack of endothelialization over stent struts is not the only mechanism determining acute coronary syndromes late after stent implantation. In-stent neoatherosclerosis, frequently disregarded, is another possible actor especially of very late thrombotic events. However, the pathogenesis of this phenomenon has not been clearly established.