In-stent neointimal characteristics and late neointimal response after drug-eluting stent implantation: A preliminary observation.
BACKGROUND
Progressive neointimal proliferation may lead to late restenosis and/or neoatherosclerosis after drug-eluting stent (DES) implantation. Late neointimal response may be different among different tissue characteristics. The aim of this study was to assess impact of in-stent neointimal characteristics on late neointimal response following DES implantation.


METHODS
Serial (median 270 days and median 551 days after stent implantation) optical coherence tomography (OCT) examinations were performed in 42 stented lesions from 26 patients. In-stent neointimal tissue was categorized as either homogeneous or heterogeneous neointima based on the OCT appearance at 1st follow-up. Serial changes in neointimal area (NIA) were compared between lesions with homogeneous neointima and those with heterogeneous neointima.


RESULTS
At first follow-up, homogeneous neointima was observed in 22 (52%) and heterogeneous neointima in 20 (48%) lesions, respectively. During follow-up, NIA in lesions with homogeneous neointima decreased significantly (1.8±0.93 mm(2) to 1.5±0.88 mm(2), p<0.001). On the other hand, NIA in lesions with heterogeneous neointima did not change significantly (2.7±1.8 mm(2) to 2.8±1.6 mm(2), p=0.658). Homogeneous neointima was the only predictor of late neointimal regression (late neointimal regression defined as NIA at first follow-up - NIA at second follow-up <0) by multivariable analysis (odds ratio=7.591, 95% confidence interval: 1.616-35.67, p=0.010).


CONCLUSIONS
OCT characteristics of neointima after DES implantation may be related to late neointimal progression or regression.
Division of Cardiology, Kawasaki Medical School, Kurashiki, Japan. Electronic address: kenzofukuhara@yahoo.co.jp.
Kenzo
K
Fukuhara
Division of Cardiology, Kawasaki Medical School, Kurashiki, Japan.
Hiroyuki
H
Okura
Division of Cardiology, Kawasaki Medical School, Kurashiki, Japan.
Teruyoshi
T
Kume
Division of Cardiology, Kawasaki Medical School, Kurashiki, Japan.
Ryotaro
R
Yamada
Division of Cardiology, Kawasaki Medical School, Kurashiki, Japan.
Yoji
Y
Neishi
Division of Cardiology, Kawasaki Medical School, Kurashiki, Japan.
Shiro
S
Uemura
D000368:Aged; D023921:Coronary Stenosis / Q000628:therapy*; D054855:Drug-Eluting Stents; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D058426:Neointima / Q000000981:diagnostic imaging*; D012189:Retrospective Studies; D041623:Tomography, Optical Coherence
Drug-eluting stent; Neointima; Optical coherence tomography