Different Neoatherosclerosis Patterns in Drug-Eluting- and Bare-Metal Stent Restenosis - Optical Coherence Tomography Study.

BACKGROUND

There are few reports about the differences between drug-eluting stents (DES) and bare metal stents (BMS) in neoatherosclerosis associated with in-stent restenosis (ISR), so we compared the frequency and characteristics of neoatherosclerosis with ISR evaluated by optical coherence tomography (OCT) in the present study.

METHODS AND RESULTS

Between March 2009 and November 2016, 98 consecutive patients with ISR who underwent diagnostic OCT were enrolled: 34 patients had a BMS, 34 had a 1st-generation DES, and 30 had a 2nd-generation DES. Neoatherosclerosis was defined as a lipid neointima (including a thin-cap fibroatheroma [TCFA] neointima, defined as a fibroatheroma with a fibrous cap <65 µm) or calcified neointima. As a result, lipid neointima, TCFA neointima and calcified neointima were detected in 39.8%, 14.3%, and 5.1%, respectively, of all patients. The frequency of neoatherosclerosis was significantly greater with DES than BMS (48.4% vs. 23.5%, P=0.018). The minimum fibrous cap thickness was significantly thicker with DES than BMS (110.3±41.1 µm vs. 62.5±17.1 µm, P<0.001). In addition, longitudinal extension of neoatherosclerosis in the stented segment was less with DES than BMS (20.2±15.1% vs. 71.8±27.1%, respectively, P=0.001).

CONCLUSIONS

OCT imaging demonstrated that neoatherosclerosis with ISR was more frequent with DES than BMS and its pattern exhibited a more focal and thick fibrous cap as compared with BMS.