title: Clinical and pathological characteristics of homogeneous and nonhomogeneous tissue of in-stent restenosis visualized by optical coherence tomography.
abstract: BACKGROUND
  Although it is known that in-stent restenosis (ISR) patterns appear homogeneous or nonhomogeneous by optical coherence tomography (OCT), interpretations of the ISR inflammatory response, of the OCT image, and its pathological implications are unclear. The aim of this study was to use OCT to characterize ISR and its inflammatory index in patients after coronary stenting.
  
  
  METHODS
  OCT was performed at follow-up in 100 angiographic ISR lesions. ISR lesions were divided into two groups: (a) homogeneous (n=48) and (b) nonhomogeneous (n=52) image groups. We assessed the ISR images produced by OCT for tissue heterogeneity and neo-intimal hyperplasia using the normalized standard deviation of OCT signal-intensity (OCT-NSD) observed in neo-intimal hyperplasia tissue. In some patients with a nonhomogeneous OCT image, we collected pathological tissue.
  
  
  RESULTS
  The prevalence of drug-eluting stents was 48% in the nonhomogeneous group and 29% in the homogeneous group (P=0.05). The OCT-NSD value in the nonhomogeneous group (0.223±0.019) was significantly higher than that in the homogeneous group (0.203±0.025; P<0.0001). Pathological tissue showed fibrin thrombi with infiltrating macrophage in 12 cases of nonhomogeneous ISR. The area under the receiver operating characteristic curve for the prediction of a nonhomogeneous image was 0.73 for OCT-NSD (95% confidence interval: 0.62-0.83: P<0.0001). The odds ratio for the prediction of a nonhomogeneous image was 3.47 (95% confidence interval: 1.18-10.2: P=0.02) for smoking by logistic regression analysis.
  
  
  CONCLUSIONS
  Nonhomogeneous ISR visualized by OCT showed a high OCT-NSD value, which was a useful predictor for nonhomogeneous images. Moreover, the nonhomogeneous ISR image visualized by OCT may show chronic inflammation and fibrin thrombi.
authors.affiliation: aThe Department of Internal Medicine, Division of Cardiology, Memorial Heart Center bDivision of Pathology, Iwate Medical University, Iwate Departments of cCardiology dPathology, Hachinohe Red Cross Hospital, Aomori eDepartment of Cardiology, Iwate Prefectural Ninohe Hospital, Ninohe fDepartment of Internal Medicine, Division of Cardiovascular Medicine, Nephrology, and Endocrinology, Iwate Medical University, Iwate, Japan.
authors.forename: Tomonori
authors.initials: T
authors.lastname: Itoh
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Fusazaki
authors.forename: Takumi
authors.initials: T
authors.lastname: Kimura
authors.forename: Hiroki
authors.initials: H
authors.lastname: Oikawa
authors.forename: Shunichi
authors.initials: S
authors.lastname: Sasou
authors.forename: Yu
authors.initials: Y
authors.lastname: Ishikawa
authors.forename: Iwao
authors.initials: I
authors.lastname: Goto
authors.forename: Kentaro
authors.initials: K
authors.lastname: Komuro
authors.forename: Satoshi
authors.initials: S
authors.lastname: Nakajima
authors.forename: Yorihiko
authors.initials: Y
authors.lastname: Koeda
authors.forename: Kyosuke
authors.initials: K
authors.lastname: Kaneko
authors.forename: Osamu
authors.initials: O
authors.lastname: Nishiyama
authors.forename: Motoyuki
authors.initials: M
authors.lastname: Nakamura
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Morino
mesh_terms: D000368:Aged; D019540:Area Under Curve; D015415:Biomarkers / Q000032:analysis; D001706:Biopsy; D016009:Chi-Square Distribution; D017023:Coronary Angiography; D023903:Coronary Restenosis / Q000000981:diagnostic imaging / Q000209:etiology / Q000378:metabolism / Q000473:pathology*; D003328:Coronary Thrombosis / Q000209:etiology / Q000473:pathology; D003331:Coronary Vessels / Q000737:chemistry / Q000000981:diagnostic imaging / Q000473:pathology*; D054855:Drug-Eluting Stents; D005260:Female; D005337:Fibrin / Q000032:analysis; D006801:Humans; D006965:Hyperplasia; D007150:Immunohistochemistry; D007249:Inflammation / Q000000981:diagnostic imaging / Q000209:etiology / Q000378:metabolism / Q000473:pathology*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D058426:Neointima; D015588:Observer Variation; D016017:Odds Ratio; D062645:Percutaneous Coronary Intervention / Q000009:adverse effects* / Q000295:instrumentation*; D011237:Predictive Value of Tests; D011474:Prosthesis Design; D012372:ROC Curve; D015203:Reproducibility of Results; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects; D041623:Tomography, Optical Coherence; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D005337:Fibrin