title: Adjunct brachytherapy: a new concept to prevent intimal hyperplasia after surgical endarterectomy?
abstract: OBJECTIVE
  Endarterectomy represents a therapeutical option for patients with advanced coronary artery disease. The mid-term results are compromised by restenosis due to neointima formation. The aim of this study was to evaluate a new treatment concept - endarterectomy with consecutive gamma-irradiation - in a rat model.
  
  
  METHODS
  Male Sprague-Dawley rats underwent left carotid endarterectomy with removal of intima: control (n=10) or were irradiated with 15 Gray (Gy) (n=13) or 20 Gy (n=10) postoperatively and compared with sham-operated rats (n=10). After 3 weeks, carotid arteries were perfusion-fixed and vessel compartment areas were measured. Transmission electron microscopy and immunohistochemical staining were used to confirm neointima formation.
  
  
  RESULTS
  Three weeks after endarterectomy, neointimal hyperplasia was found in the control group (0.07+/-0.04 mm(2)). After irradiation, a dose-dependent reduction of neointima was observed (0.003 mm(2) at 15 Gy and 0.0007 mm(2) at 20 Gy, P<0.0001). However, immunohistochemical staining revealed that thin re-endothelialization after irradiation was not inhibited.
  
  
  CONCLUSIONS
  Gamma-irradiation significantly suppressed neointimal hyperplasia in a rat model of surgical endarterectomy. Despite inhibition of intimal hyperplasia, re-endothelialization after adjuvant brachytherapy was present. Adjuvant brachytherapy may be therefore a new concept to prevent restenosis after endarterectomy in patients.
authors.affiliation: Department of Cardiac Surgery, University of Heidelberg, INF 110, 69120 Heidelberg, Germany. Carsten.Beller@urz.uni-heidelberg
authors.forename: Carsten J
authors.initials: CJ
authors.lastname: Beller
authors.forename: Jens
authors.initials: J
authors.lastname: Kosse
authors.forename: Tamás
authors.initials: T
authors.lastname: Radovits
authors.forename: Robert
authors.initials: R
authors.lastname: Krempien
authors.forename: Marie-Luise
authors.initials: ML
authors.lastname: Gross
authors.forename: Irina
authors.initials: I
authors.lastname: Berger
authors.forename: Siegfried
authors.initials: S
authors.lastname: Hagl
authors.forename: Gábor
authors.initials: G
authors.lastname: Szabó
mesh_terms: D000818:Animals; D001918:Brachytherapy / Q000379:methods*; D002339:Carotid Arteries / Q000378:metabolism / Q000473:pathology* / Q000648:ultrastructure; D004195:Disease Models, Animal; D004307:Dose-Response Relationship, Radiation; D016894:Endarterectomy, Carotid / Q000009:adverse effects*; D004730:Endothelium, Vascular / Q000502:physiology; D005720:Gamma Rays / Q000627:therapeutic use; D006133:Growth Substances / Q000378:metabolism; D006965:Hyperplasia / Q000209:etiology / Q000517:prevention & control; D008297:Male; D008854:Microscopy, Electron; D018714:Radiotherapy, Adjuvant; D051381:Rats; D017207:Rats, Sprague-Dawley; D012038:Regeneration / Q000528:radiation effects; D055502:Secondary Prevention; D017539:Tunica Intima / Q000473:pathology* / Q000601:surgery / Q000648:ultrastructure; D014666:Vasomotor System / Q000528:radiation effects
chemical_list: D006133:Growth Substances