title: [The functional expectations of valve bioprostheses. I. Physical and histopathological tests for the use of sections of bovine pericardium].
abstract: OBJECTIVE
  The heterogenicity of the bovine pericardium sac regarding its elasticity, extensibility and thickness encouraged the work with the purpose to study the different areas of pericardium, mapped according to its position on the heart.
  
  
  METHODS
  Ten bovine pericardium sacs previously selected and obtained at the slaughterhouse immediately after the animal slaughter were utilized. The pericardia were sectioned sagittally from the anterior to the posterior portion, thus obtaining two parts, right and left. Two areas were demarcated for each one of them amounting to four regions: A, B, C and D. Each of the four regions was divided into two regions: 1 and 1, amounting to 80 samples. There have been physical tests (shrinkage and mechanical resistance), histopathological studies and statistical analysis were done.
  
  
  RESULTS
  The right ventricle area (region D) had the best utilization (21.3%), and then the left ventricle area (region B, 16.2%). The physical tests on the utilized samples showed minimum and maximum values of 0.20 and 0.40 mm for the thickness, 2.0 and 7.0 kgf for force, 1.6 and 4.2 kgf/mm2 for rupture, 18 and 36% for stretching, 15 and 65 for tenacity index and 85 and 87 degrees C for shrinkage. The region D presented histologically and more preserved, either for the collagen fibers or the elastic ones.
  
  
  CONCLUSIONS
  The results of the statistical analysis proved the need to increase the sample size to certify the existence of a sectioning of the pericardium and a more adequate position of the proof body (longitudinal, transversal and oblique) when obtaining the pericardium flap to make the valve bioprosthesis.
authors.forename: D M
authors.initials: DM
authors.lastname: Braile
authors.forename: M J
authors.initials: MJ
authors.lastname: Soares
authors.forename: D R
authors.initials: DR
authors.lastname: Souza
authors.forename: V A
authors.initials: VA
authors.lastname: Ramires
authors.forename: S
authors.initials: S
authors.lastname: Suzigan
authors.forename: M F
authors.initials: MF
authors.lastname: Lourenço
mesh_terms: D000818:Animals; D001705:Bioprosthesis; D002417:Cattle; D006350:Heart Valve Prosthesis; D006801:Humans; D008422:Materials Testing / Q000379:methods; D010496:Pericardium / Q000473:pathology / Q000502:physiology*; D011474:Prosthesis Design; D013718:Tensile Strength
vernacular_title: Expectativa funcional de biopróteses valvulares. I. Testes físicos e histopatológicos para aproveitamento de regiões de pericárdio bovino.