title: Delayed coverage in malapposed and side-branch struts with respect to well-apposed struts in drug-eluting stents: in vivo assessment with optical coherence tomography.
abstract: BACKGROUND
  Pathology studies on fatal cases of very late stent thrombosis have described incomplete neointimal coverage as common substrate, in some cases appearing at side-branch struts. Intravascular ultrasound studies have described the association between incomplete stent apposition (ISA) and stent thrombosis, but the mechanism explaining this association remains unclear. Whether the neointimal coverage of nonapposed side-branch and ISA struts is delayed with respect to well-apposed struts is unknown.
  
  
  RESULTS
  Optical coherence tomography studies from 178 stents implanted in 99 patients from 2 randomized trials were analyzed at 9 to 13 months of follow-up. The sample included 38 sirolimus-eluting, 33 biolimus-eluting, 57 everolimus-eluting, and 50 zotarolimus-eluting stents. Optical coherence tomography coverage of nonapposed side-branch and ISA struts was compared with well-apposed struts of the same stent by statistical pooled analysis with a random-effects model. A total of 34 120 struts were analyzed. The risk ratio of delayed coverage was 9.00 (95% confidence interval, 6.58 to 12.32) for nonapposed side-branch versus well-apposed struts, 9.10 (95% confidence interval, 7.34 to 11.28) for ISA versus well-apposed struts, and 1.73 (95% confidence interval, 1.34 to 2.23) for ISA versus nonapposed side-branch struts. Heterogeneity of the effect was observed in the comparison of ISA versus well-apposed struts (H=1.27; I(2)=38.40) but not in the other comparisons.
  
  
  CONCLUSIONS
  Coverage of ISA and nonapposed side-branch struts is delayed with respect to well-apposed struts in drug-eluting stents, as assessed by optical coherence tomography. Clinical Trial Registration- http://www.clinicaltrials.gov. Unique identifier: NCT00389220, NCT00617084.
authors.affiliation: Erasmus Medical Centre, Thoraxcenter, Rotterdam, Netherlands.
authors.forename: Juan Luis
authors.initials: JL
authors.lastname: Gutiérrez-Chico
authors.forename: Evelyn
authors.initials: E
authors.lastname: Regar
authors.forename: Eveline
authors.initials: E
authors.lastname: Nüesch
authors.forename: Takayuki
authors.initials: T
authors.lastname: Okamura
authors.forename: Joanna
authors.initials: J
authors.lastname: Wykrzykowska
authors.forename: Carlo
authors.initials: C
authors.lastname: di Mario
authors.forename: Stephan
authors.initials: S
authors.lastname: Windecker
authors.forename: Gerrit-Anne
authors.initials: GA
authors.lastname: van Es
authors.forename: Pierre
authors.initials: P
authors.lastname: Gobbens
authors.forename: Peter
authors.initials: P
authors.lastname: Jüni
authors.forename: Patrick W
authors.initials: PW
authors.lastname: Serruys
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000379:methods / Q000706:statistics & numerical data*; D023903:Coronary Restenosis / Q000175:diagnosis* / Q000453:epidemiology*; D003331:Coronary Vessels; D054855:Drug-Eluting Stents / Q000009:adverse effects / Q000706:statistics & numerical data*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data*; D012307:Risk Factors; D041623:Tomography, Optical Coherence