title: Ovine femoral artery bypass grafting using saphenous vein: a new model.
abstract: BACKGROUND
  Saphenous vein grafts (SVGs) are frequently used for multi-vessel coronary artery bypass grafting and peripheral arterial bypasses; however, the estimated 40% failure rate within the first 5 y due to intimal hyperplasia (IH) and the subsequent failure rate of 2%-4% per year pose a significant clinical problem. Here, we report a surgical model in sheep intended to study IH development in SVGs, which can also be used for the evaluation of potential alternative treatments.
  
  
  METHODS
  Autologous bilateral SVGs were implanted as femoral artery interposition grafts using end-to-side anastomoses in adult sheep (n = 23), which were survived for 30 (n = 6), 90 (n = 7), 180 (n = 7), or 365 (n = 3) days. Post-implant, mid-term, and pretermination angiograms were quantified, and harvested SVGs were evaluated using quantitative histomorphometry.
  
  
  RESULTS
  We describe a peripheral arterial surgical technique that models the progression of SVG pathology. Angiographic analysis showed a progressive dilation of SVGs leading to worsening diametrical matching to the target artery and reduced blood flow; and histomorphometry data showed an increase in IH over time. Multivariable regression analysis suggested that statistically significant (P < 0.05) time-dependent relationships exist between SVG dilation and both reduction in blood flow and IH development.
  
  
  CONCLUSIONS
  Bilateral SVGs implanted onto the femoral arteries of sheep produced, controlled and consistent angiographic and histomorphometric results for which direct correlations could be made. This preclinical investigation model can be used as a robust tool to evaluate therapies intended for cardiovascular pathologies such as occlusive IH in SVGs.
authors.affiliation: Neograft Technologies, Inc, Taunton, Massachusetts. Electronic address: mkurdi@neograftinc.com.
authors.forename: Mohammed S
authors.initials: MS
authors.lastname: El-Kurdi
authors.affiliation: Neograft Technologies, Inc, Taunton, Massachusetts.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Soletti
authors.affiliation: Fundacion Favaloro, Buenos Aires, Argentina.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Nieponice
authors.affiliation: University of Buenos Aires, Buenos Aires, Argentina.
authors.forename: Gustavo
authors.initials: G
authors.lastname: Abuin
authors.affiliation: American Preclinical Services, Minneapolis, Minnesota.
authors.forename: Christina
authors.initials: C
authors.lastname: Gross
authors.affiliation: Alizée Pathology, Thurmont, Maryland.
authors.forename: Serge
authors.initials: S
authors.lastname: Rousselle
authors.affiliation: Department of Surgery, Loyola University, Maywood, Illinois; Research Services, Hines VA Hospital, Hines, Illinois.
authors.forename: Howard
authors.initials: H
authors.lastname: Greisler
authors.affiliation: Neograft Technologies, Inc, Taunton, Massachusetts.
authors.forename: Jonathan
authors.initials: J
authors.lastname: McGrath
mesh_terms: D000714:Anastomosis, Surgical / Q000379:methods; D000818:Animals; D001026:Coronary Artery Bypass; D004195:Disease Models, Animal; D005260:Female; D005263:Femoral Artery / Q000601:surgery*; D006083:Graft Occlusion, Vascular / Q000473:pathology*; D006965:Hyperplasia / Q000473:pathology / Q000601:surgery; D008297:Male; D012501:Saphenous Vein / Q000637:transplantation*; D034561:Sheep, Domestic; D020858:Tissue and Organ Harvesting / Q000379:methods; D017539:Tunica Intima / Q000473:pathology / Q000601:surgery; D014652:Vascular Diseases / Q000473:pathology / Q000601:surgery*
keywords: Anastomosis; Bypass graft; End-to-side; Femoral artery; No-touch vein harvest; Saphenous vein