title: Morphological differences of tissue characteristics between early, late, and very late restenosis lesions after first generation drug-eluting stent implantation: an optical coherence tomography study.
abstract: OBJECTIVE
  Restenosis of drug-eluting stents (DESs) might be different from that of bare metal stent restenosis in diverse ways including mechanisms and time course; however, these have not been fully examined. To gain insight into the mechanisms and time course of DES restenosis, we evaluated the characteristics of restenotic lesions of first generation DES using optical coherence tomography (OCT).
  
  
  RESULTS
  We compared the morphological characteristics of early in-stent restenosis (<1 year: E-ISR, n = 43), late ISR (1-3 years: L-ISR, n = 22), and very late ISR (>3 years: VL-ISR, n = 21). OCT qualitative restenotic tissue analysis included the assessment of tissue structure [homogeneous or four types of heterogeneous intima (thin-cap fibroatheroma (TCFA)-like, layered, patchy or speckled pattern)], the presence of the peri-strut low intensity area (PLIA), microvessels, disruption with cavity, and intraluminal material and was performed at every 1 mm slice of the entire stent length. In addition to a greater trend for heterogeneous intima at the later phase, TCFA-like pattern image, intra-intima microvessels were increased from the early to the very late phase. On the other hand, the speckled pattern image was decreased from the early to the very late phase.
  
  
  CONCLUSIONS
  The OCT morphological characteristics of DES restenotic tissue varied at different time-points. OCT images in early DES ISR might be associated with delayed arterial healing, and neoatherosclerosis might contribute to late catch-up phenomenon (L-ISR and VL-ISR) after DES implantation.
authors.affiliation: Toyohashi Heart Center, 21-1 Gobudori, Oyama-cho, Toyohashi, Japan.
authors.forename: Maoto
authors.initials: M
authors.lastname: Habara
authors.forename: Mitsuyasu
authors.initials: M
authors.lastname: Terashima
authors.forename: Kenya
authors.initials: K
authors.lastname: Nasu
authors.forename: Hideaki
authors.initials: H
authors.lastname: Kaneda
authors.forename: Daisuke
authors.initials: D
authors.lastname: Yokota
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Ito
authors.forename: Tairo
authors.initials: T
authors.lastname: Kurita
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Teramoto
authors.forename: Masashi
authors.initials: M
authors.lastname: Kimura
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Kinoshita
authors.forename: Etsuo
authors.initials: E
authors.lastname: Tsuchikane
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Asakura
authors.forename: Takahiko
authors.initials: T
authors.lastname: Suzuki
mesh_terms: D000368:Aged; D017023:Coronary Angiography; D023903:Coronary Restenosis / Q000175:diagnosis* / Q000209:etiology*; D054855:Drug-Eluting Stents / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D011446:Prospective Studies; D015203:Reproducibility of Results; D012307:Risk Factors; D012984:Software; D013997:Time Factors; D041623:Tomography, Optical Coherence