title: Histology and electron microscopy of explanted bifurcated endovascular aortic grafts: evidence of early incorporation and healing.
abstract: OBJECTIVE
  To report an examination of explanted bifurcated endovascular aortic grafts for histologic evidence of early healing and incorporation.
  
  
  METHODS
  Two bifurcated endovascular aortic grafts composed of polycarbonate urethane and Elgiloy wire were explanted 42 and 21 days after successful endovascular exclusion of abdominal aortic aneurysms. Both patients expired from causes unrelated to endograft deployment. The explanted devices were examined using immunohistochemical analysis and electron microscopy.
  
  
  RESULTS
  On explantation, both grafts appeared to have excluded the aneurysm with no evidence of endoleak, graft migration, or thrombosis. Histological examination showed numerous inflammatory cells and good ingrowth of tissue into the proximal 2 cm of the graft. Collagen and smooth muscle cells were evident in the proximal portion of the graft with only collagen in the distal segments. Neointimal formation was seen within the proximal 2 cm also, but not at the distal segments. Macrophages were present in the graft. Scanning electron microscopy showed an extensive matrix of fibers that most likely represented collagen.
  
  
  CONCLUSIONS
  Bifurcated endovascular aortic grafts show inflammatory and mild foreign body reactions, collagen formation, and intimal ingrowth during healing. These findings are similar to some of the healing properties reported for sutured grafts, as well as other endovascular grafts.
authors.affiliation: Department of Surgery, State University of New York Health Science Center at Brooklyn 11203, USA.
authors.forename: C K
authors.initials: CK
authors.lastname: Shin
authors.forename: W
authors.initials: W
authors.lastname: Rodino
authors.forename: J D
authors.initials: JD
authors.lastname: Kirwin
authors.forename: J A
authors.initials: JA
authors.lastname: Ramirez
authors.forename: W
authors.initials: W
authors.lastname: Wisselink
authors.forename: G
authors.initials: G
authors.lastname: Papierman
authors.forename: T F
authors.initials: TF
authors.lastname: Panetta
mesh_terms: D000199:Actins / Q000276:immunology; D000368:Aged; D000906:Antibodies / Q000032:analysis; D001012:Aorta, Abdominal / Q000276:immunology / Q000601:surgery / Q000648:ultrastructure*; D017544:Aortic Aneurysm, Abdominal / Q000473:pathology / Q000601:surgery*; D019917:Blood Vessel Prosthesis Implantation; D020099:Coated Materials, Biocompatible; D003094:Collagen / Q000648:ultrastructure; D004730:Endothelium, Vascular / Q000276:immunology / Q000648:ultrastructure; D005169:Factor VIII / Q000276:immunology; D017809:Fatal Outcome; D005260:Female; D005549:Foreign-Body Reaction / Q000276:immunology / Q000473:pathology; D015743:Giant Cells, Foreign-Body / Q000276:immunology / Q000648:ultrastructure; D006801:Humans; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000276:immunology / Q000648:ultrastructure; D011108:Polymers; D011140:Polyurethanes; D014945:Wound Healing
chemical_list: D000199:Actins; D000906:Antibodies; D020099:Coated Materials, Biocompatible; D011108:Polymers; D011140:Polyurethanes; C110029:poly(carbonate urea) urethane; D005169:Factor VIII; D003094:Collagen