title: Microscopic and ultrastructural evaluation of the saphenous vein endothelium for CABG prepared by the no touch technique.
abstract: OBJECTIVE
  Saphenous vein grafts (SV) used in coronary artery bypass grafting have a limited life and vein occlusion may be the final adverse effect. Efforts to develop new techniques to harvest the saphenous vein may improve the viability of the graft.
  
  
  METHODS
  Twenty patients were randomly divided into two groups with the objective of evaluating the vascular endothelium. The No Touch (NT) technique consists in removing the saphenous vein with perivascular tissue. The conventional technique consists in harvesting with "in situ" removal of the perivascular tissue. The standard saphenous vein harvesting procedure used bridged incisions. Characteristics of the vein were considered. Evaluation of the endothelium was achieved by electron microscopy and histologic analysis using hematoxylin eosin staining. The Picrosirius and Masson Trichrome methods were used to analyze subendothelial collagen.
  
  
  RESULTS
  Electron microscopy demonstrated that the NT Group had larger non-denudated endothelial areas as well as a smaller number of degraded cells. Histological analysis showed the form and integrity of the saphenous vein layers. A larger amount of collagen fibers were identified in the NT Group.
  
  
  CONCLUSIONS
  The NT technique better preserves the saphenous vein endothelium suggesting a more viable graft in the long term.
authors.affiliation: Universidade Federal de São Paulo, Escola Paulista de Medicina, Sao Paulo, Brazil. virepm71@yahoo.com.br
authors.forename: Virgílio Figueiredo
authors.initials: VF
authors.lastname: Silva
authors.forename: Márcia Marcelino de Souza
authors.initials: MM
authors.lastname: Ishigai
authors.forename: Edna
authors.initials: E
authors.lastname: Freymüller
authors.forename: João Nelson Rodrigues
authors.initials: JN
authors.lastname: Branco
authors.forename: Diego Felipe
authors.initials: DF
authors.lastname: Gaia
authors.forename: Edmo Atique
authors.initials: EA
authors.lastname: Gabriel
authors.forename: Renata Aparecida Leonel
authors.initials: RA
authors.lastname: Romão
authors.forename: Enio
authors.initials: E
authors.lastname: Buffolo
mesh_terms: D001391:Azo Compounds; D003094:Collagen / Q000648:ultrastructure*; D004396:Coloring Agents; D001026:Coronary Artery Bypass / Q000379:methods*; D004730:Endothelium, Vascular / Q000648:ultrastructure*; D004801:Eosine Yellowish-(YS); D006416:Hematoxylin; D006801:Humans; D008739:Methyl Green; D012501:Saphenous Vein / Q000166:cytology / Q000637:transplantation / Q000648:ultrastructure*; D020858:Tissue and Organ Harvesting / Q000379:methods*
chemical_list: D001391:Azo Compounds; D004396:Coloring Agents; C017768:trichrome stain; D008739:Methyl Green; D003094:Collagen; D004801:Eosine Yellowish-(YS); D006416:Hematoxylin