title: [Instent restenosis related to vessel injury score degree. Are current experimental models valid for drug-eluting stents analysis?].
abstract: OBJECTIVE
  Drug-eluting stents are useful for preventing restenosis, but the patho-physiological processes involved in the proliferative response after implantation are still not known in detail. The aim of this study is to compare the coronary vascular histomorphometry after implanting drug-eluting stents and bare metal stents in a swine model.
  
  
  METHODS
  Sixty stents were randomly implanted in 20 Large White female pigs with a ratio of baremetal/drug-eluting stents of 1:2. After 28 days, euthanasia and histomorphometry were performed. We defined the vessel injury score in accordance to whether the internal elastic lamina was intact or ruptured.
  
  
  RESULTS
  There were no differences between drug-eluting stents and bare metal stents in the intact internal elastic lamina group regarding neointimal area or % restenosis (1.3 [1.1-2.2]) vs 2.0 [1.3-2.5] mm²; P=.6; and 14.0 [12.1-20.8] vs 22.2 [14.1-23.3] %; P=.5). We assessed statistically significant differences for the ruptured internal elastic lamina group, (neointimal area 1.2 [0.8-2.0] vs 2.9 [2.3-3.7] mm²; P=.001 and % restenosis 16.63 [11.2-23.5] vs 30.4 [26.4-45.7] %; P=.001).
  
  
  CONCLUSIONS
  In our swine model, we did not find any differences between proliferative response of drug-eluting stents and bare metal stents when the internal elastic lamina is intact; differences are only found when vascular injury is deeper.
authors.affiliation: Fundación Investigación Sanitaria e Instituto de Biomedicina (IBIOMED) de León, Complejo Asistencial Universitario, León, España. alejandrodiego@secardiologia.es
authors.forename: Alejandro
authors.initials: A
authors.lastname: Diego
authors.forename: Armando
authors.initials: A
authors.lastname: Pérez de Prado
authors.forename: Carlos
authors.initials: C
authors.lastname: Cuellas
authors.forename: Claudia
authors.initials: C
authors.lastname: Pérez-Martínez
authors.forename: Manuel
authors.initials: M
authors.lastname: Gonzalo-Orden
authors.forename: Jose R
authors.initials: JR
authors.lastname: Altonaga
authors.forename: Antonio
authors.initials: A
authors.lastname: de Miguel
authors.forename: Marta
authors.initials: M
authors.lastname: Regueiro
authors.forename: Jose
authors.initials: J
authors.lastname: Ajenjo
authors.forename: Fernando
authors.initials: F
authors.lastname: Sánchez-Lasheras
authors.forename: Angel
authors.initials: A
authors.lastname: Alvarez-Arenal
authors.forename: Felipe
authors.initials: F
authors.lastname: Fernández-Vázquez
mesh_terms: D000818:Animals; D049109:Cell Proliferation / Q000187:drug effects; D023903:Coronary Restenosis / Q000473:pathology*; D003331:Coronary Vessels / Q000473:pathology*; D054855:Drug-Eluting Stents; D005260:Female; D008954:Models, Biological; D058426:Neointima / Q000473:pathology; D015607:Stents; D013552:Swine