Thrombus-related focal in-stent restenosis after everolimus-eluting stent implantation

A 60-year-old man who had received repeated angioplasty for silent ischemia was suspected to have restenosis based on radioisotope imaging (exercise-RI) findings 6 months after everolimus-eluting stent (EES) implantation (3.5 × 28, 3.5 × 28, 3.0 × 18 mm). The stents had been implanted for chronic total occlusion of the right coronary artery (RCA), and the patient was on continuous dual antiplatelet therapy. Diagnostic angiography demonstrated in-stent restenosis in the proximal RCA, which was treated by optical coherence tomography (OCT)-guided cutting balloon angioplasty with distal protection. OCT findings of the stenotic segment before angioplasty showed that the lesion had complex features. The lesion was successfully dilated, and whitish material obtained by a distal protection device was composed of fibrin thrombi with neutrophils and small pieces of mature fibrocellular neointima. The mechanisms and patterns of restenosis after EES placement have not been well clarified. This case may reflect a restenosis pattern (i.e., asymptomatic, focal, and thrombi-related) in the era of the newer generation of drug-eluting stents.