title: Serial Optical Coherence Tomography Evaluation at 6, 12, and 24 Months After Biolimus A9-Eluting Biodegradable Polymer-Coated Stent Implantation.
abstract: BACKGROUND
  The Nobori (Terumo Corporation, Tokyo, Japan) is a biolimus A9-eluting stent (BES) featured with a biodegradable polymer coated on the abluminal side only. We previously reported that favourable vessel healing was achieved at 6-12 months after BES implantation. However, detailed long-term vessel reaction after BES deployment is unclear.
  
  
  METHODS
  Twenty-two BESs were serially evaluated using optical coherence tomography (OCT) at 6, 12, and 24 months after stenting. Average neointimal thickness, uncovered struts, and neointimal unevenness score (each cross-section as maximum neointimal thickness in 1 cross section divided by the average neointimal thickness of the same cross-section) were manually measured. In addition, we evaluated the percentage of struts with peri-strut low-intensity area (a region around stent struts that homogenously showed less intensity than the surrounding tissue, which suggests fibrin deposition or impaired neointima maturation), thrombi, and atherogenic neointimas (neointimas containing a diffuse border and poor-signal region with invisible struts due to marked signal attenuation).
  
  
  RESULTS
  Serial OCT observation revealed a small gradual increase in neointimal thickness from 6 to 24 months (73 ± 24 μm; 81 ± 26 μm; and 108 ± 35 μm, respectively, P = 0.001) with a nonsignificant decrease in the lumen area (6.36 ± 1.98 mm(2); 6.18 ± 2.04 mm(2); and 5.87 ± 2.06 mm(2); P = 0.72). Frequency of uncovered struts (3.89 ± 3.91%; 1.55 ± 1.63%; and 0.23 ± 0.67%; P = 0.001), neointimal unevenness score (1.95 ± 0.18% to 1.86 ± 0.19% to 1.78 ± 0.17; P = 0.012), percentage of thrombi (5%, 0%, and 0%; P = 0.37) and peri-strut low-intensity area (6.8%, 5.1%, and 1.6%; P = 0.017) decreased from 6 to 12 and 24 months. Atherogenic neointima was not observed in the event-free OCT cohort.
  
  
  CONCLUSIONS
  The Nobori stent achieved acceptable long-term vessel healing, mostly without adverse vessel reactions.
authors.affiliation: Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan.
authors.forename: Akihide
authors.initials: A
authors.lastname: Konishi
authors.affiliation: Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan. Electronic address: shinke@med.kobe-u.ac.jp.
authors.forename: Toshiro
authors.initials: T
authors.lastname: Shinke
authors.affiliation: Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan.
authors.forename: Hiromasa
authors.initials: H
authors.lastname: Otake
authors.affiliation: Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan.
authors.forename: Tomofumi
authors.initials: T
authors.lastname: Takaya
authors.affiliation: Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Osue
authors.affiliation: Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan.
authors.forename: Hiroto
authors.initials: H
authors.lastname: Kinutani
authors.affiliation: Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan.
authors.forename: Masaru
authors.initials: M
authors.lastname: Kuroda
authors.affiliation: Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan.
authors.forename: Hachidai
authors.initials: H
authors.lastname: Takahashi
authors.affiliation: Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Terashita
authors.affiliation: Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan.
authors.forename: Junya
authors.initials: J
authors.lastname: Shite
authors.affiliation: Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan.
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Hirata
mesh_terms: D000368:Aged; D020099:Coated Materials, Biocompatible; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000601:surgery*; D003331:Coronary Vessels / Q000473:pathology* / Q000601:surgery; D054855:Drug-Eluting Stents; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D058426:Neointima; D011108:Polymers; D011446:Prospective Studies; D011474:Prosthesis Design; D015203:Reproducibility of Results; D020123:Sirolimus / Q000031:analogs & derivatives* / Q000494:pharmacology; D013997:Time Factors; D041623:Tomography, Optical Coherence / Q000379:methods*; D016896:Treatment Outcome
chemical_list: D020099:Coated Materials, Biocompatible; D011108:Polymers; C518022:umirolimus; D020123:Sirolimus