title: Evaluation of in-stent neointimal tissue components using integrated backscatter intravascular ultrasound: comparison of drug-eluting stents and bare-metal stents.
abstract: Although in-stent restenosis (ISR) occurs after drug-eluting stents (DES) implantation, neointimal tissue characteristics have not been fully investigated. We assessed neointimal tissue components using integrated backscatter intravascular ultrasound (IB-IVUS) after DES and bare-metal stents (BMS) implantation. Fifty-seven consecutive patients with 61 lesions underwent repeated percutaneous coronary intervention (PCI) for the treatment of ISR (DES: 24 lesions, BMS: 37 lesions). PCI was performed using plain old balloon angioplasty (POBA). Before PCI, we assessed neointimal tissue characteristics using IB-IVUS. Neointima was divided into four categories: category 1 (-11 to -29 dB), category 2 (-29 to -35 dB), category 3 (-35 to -49 dB), and category 4 (-49 to -130 dB) according to IB values. We compared neointimal tissue components between DES and BMS. Thirty-three patients with 33 lesions (DES: 17, BMS: 16) were finally included. Neointima was predominantly composed of category 3 tissue in both groups (DES: 68 ± 8%, BMS: 73 ± 5%, P = 0.053). DES had a broader distribution of category 4 tissue component than BMS. After POBA, distal slow flow phenomenon occurred in 5 of DES (29%), whereas none of BMS. In DES, the optimal threshold of category 4 tissue to predict distal slow flow phenomenon after POBA was 30% (sensitivity: 100%, specificity: 92%). Neointima was mainly composed of category 3 tissue at ISR site, irrespective of DES or BMS. In DES, there was a subgroup with category 4 rich tissue, which caused distal slow flow phenomenon after POBA. IB-IVUS might be useful to identify vulnerable neointima in DES restenosis.
authors.affiliation: Department of Cardiovascular Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan.
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Muraoka
authors.forename: Shinjo
authors.initials: S
authors.lastname: Sonoda
authors.forename: Kuninobu
authors.initials: K
authors.lastname: Kashiyama
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Kamezaki
authors.forename: Yuki
authors.initials: Y
authors.lastname: Tsuda
authors.forename: Masaru
authors.initials: M
authors.lastname: Araki
authors.forename: Masahiro
authors.initials: M
authors.lastname: Okazaki
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Otsuji
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016009:Chi-Square Distribution; D023903:Coronary Restenosis / Q000000981:diagnostic imaging* / Q000209:etiology / Q000628:therapy*; D003331:Coronary Vessels / Q000000981:diagnostic imaging*; D054855:Drug-Eluting Stents; D005260:Female; D006801:Humans; D008297:Male; D008670:Metals; D008875:Middle Aged; D058426:Neointima; D062645:Percutaneous Coronary Intervention / Q000009:adverse effects / Q000295:instrumentation*; D011237:Predictive Value of Tests; D011474:Prosthesis Design; D012189:Retrospective Studies; D015607:Stents; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional
chemical_list: D008670:Metals