文摘
The primary aim of the present study was to assess the gray scale intravascular ultrasound (IVUS) findings that might be associated with late drug-eluting stent restenosis. The study included 47 patients (54 lesions) who had undergone either baseline IVUS-guided stent implantation or IVUS-guided repeat stenting to treat in-stent restenosis and then had IVUS follow-up data for ¡Ý1.5 years afterward without any intervening procedures. The left anterior descending artery was the culprit in 59 % of cases, and 50 % of the lesions were at bifurcation sites. Quantitative and qualitative IVUS analyses showed a decreased minimum lumen area at follow-up from 6.0 ¡À 1.8 to 3.8 ¡À 1.4 mm2 (p <0.0001) that was mainly due to neointimal hyperplasia with chronic stent recoil (defined as a >15 % decrease in minimum stent area) in only 2 lesions and stent fracture in only 5 lesions. Calcified neointima appeared in 12 lesions, mostly in the form of macrocalcification, and was associated with increased calcium both behind the stent and in the reference segment. In conclusion, late drug-eluting stent restenosis showed neointimal calcification in 20 % of cases, and chronic stent recoil was rare.