title: Vascular response after Zilver PTX stent implantation for superficial femoral artery lesions: serial optical coherence tomography findings at 6 and 12 months.
abstract: OBJECTIVE
  To compare the vascular response after paclitaxel-coated nitinol drug-eluting stent (Zilver PTX) implantation for superficial femoral artery lesions after 6 and 12 months using optical coherence tomography (OCT).
  
  
  METHODS
  Serial OCT examinations were performed in 5 patients (4 men; mean age 78.4 ± 6.8 years) with 9 Zilver PTX stents at 6- and 12-month follow-up. Variables evaluated included neointimal thickness and apposition on each strut, the incidence of extrastent lumen (ESL), peristrut low-intensity area (PLIA), and neovascularization at 1-mm intervals.
  
  
  RESULTS
  A total of 249 matched cross-section images were evaluated and included 4788 and 4826 struts at 6 and 12 months, respectively. Mean neointimal thickness significantly increased from 480 to 540 µm between 6 and 12 months (p < 0.001). The percentage of uncovered struts tended to decrease at 12 months (3% vs. 2.3%, p = 0.054), whereas the percentage of malapposed struts were similar at both examinations (0.2% vs. 0.2%, p > 0.99). Although the incidence of ESL in cross sections was not different (35% vs. 31%, p = 0.29), median ESL area significantly increased from 6 to 12 months [0.12 (0.04-0.36) vs. 0.31 (0.14-0.59) mm(2), p = 0.003)]. The presence of PLIA (29% vs. 44%, p < 0.001) and neovascularization (14% vs. 27%, p < 0.001) increased from 6 to 12 months.
  
  
  CONCLUSIONS
  These findings suggest that delayed vascular healing and persistent peristent inflammation may be present even at 12 months after Zilver PTX implantation.
authors.affiliation: Kokura Memorial Hospital, Kitakyushu, Japan mbxtg263@ybb.ne.jp.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Tomoi
authors.affiliation: Kokura Memorial Hospital, Kitakyushu, Japan.
authors.forename: Shoichi
authors.initials: S
authors.lastname: Kuramitsu
authors.affiliation: Kokura Memorial Hospital, Kitakyushu, Japan.
authors.forename: Yoshimitsu
authors.initials: Y
authors.lastname: Soga
authors.affiliation: Tsukuba Medical Center Hospital, Tsukuba, Japan.
authors.forename: Hideaki
authors.initials: H
authors.lastname: Aihara
authors.affiliation: Kokura Memorial Hospital, Kitakyushu, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Ando
authors.affiliation: Kokura Memorial Hospital, Kitakyushu, Japan.
authors.forename: Masakiyo
authors.initials: M
authors.lastname: Nobuyoshi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000497:Alloys / Q000008:administration & dosage; D002317:Cardiovascular Agents / Q000008:administration & dosage; D054855:Drug-Eluting Stents / Q000009:adverse effects; D005260:Female; D005263:Femoral Artery / Q000473:pathology*; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D058426:Neointima; D017239:Paclitaxel / Q000008:administration & dosage; D058729:Peripheral Arterial Disease / Q000175:diagnosis* / Q000628:therapy*; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012307:Risk Factors; D012680:Sensitivity and Specificity; D041623:Tomography, Optical Coherence / Q000379:methods; D016896:Treatment Outcome
chemical_list: D000497:Alloys; D002317:Cardiovascular Agents; C013616:nitinol; D017239:Paclitaxel
keywords: drug-eluting stent; endovascular therapy; inflammation; neointimal thickness; neovascularization; optical coherence tomography; stent apposition; superficial femoral artery; vascular response