title: Biomechanical Properties and Microstructural Analysis of the Human Nonaneurysmal Aorta as a Function of Age, Gender and Location: An Autopsy Study.
abstract: BACKGROUND
  The biomechanical failure properties and histological composition of the human nonaneurysmal aorta were studied.
  
  
  METHODS
  Twenty-six human aortas were harvested from fresh cadavers at autopsy. A total of 153 circumferentially oriented strips were obtained from the aortas for biomechanical and histological studies.
  
  
  RESULTS
  The failure load (6.18 ± 2.03 vs. 4.85 ± 2.04 N; p = 0.001), failure tension (19.88 ± 9.05 vs. 14.53 ± 7 N/cm; p = 0.001), failure strain (0.66 ± 0.31 vs. 0.49 ± 0.25; p = 0.003) and amount of elastic fibers (19.39 ± 15.57 vs. 14.06 ± 9.5%; p = 0.011) were all significantly higher for the thoracic than the abdominal aorta. There was a significant negative correlation between age and failure load (R = -0.35; p < 0.0001), failure stress (R = -0.63; p < 0.0001), failure tension (R = -0.52; p < 0.0001) and failure strain (R = -0.8; p < 0.0001). Male aortas had a higher failure load and failure tension than female aortas.
  
  
  CONCLUSIONS
  The thoracic aorta has a higher strength and elasticity than the abdominal aorta. The elderly have weaker and stiffer aortas than the young. Male aortas are stronger than female aortas.
authors.affiliation: Division of Vascular and Endovascular Surgery, Department of Surgery, University of Sx00E3;o Paulo School of Medicine, Sx00E3;o Paulo, Brazil.
authors.forename: Otavio Henrique
authors.initials: OH
authors.lastname: Ninomiya
authors.forename: José Augusto
authors.initials: JA
authors.lastname: Tavares Monteiro
authors.forename: Maria de Lourdes
authors.initials: Mde L
authors.lastname: Higuchi
authors.forename: Pedro
authors.initials: P
authors.lastname: Puech-Leão
authors.forename: Nelson
authors.initials: N
authors.lastname: de Luccia
authors.forename: Madhavan Lakshmi
authors.initials: ML
authors.lastname: Raghavan
authors.forename: Erasmo Simão
authors.initials: ES
authors.lastname: da Silva
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000473:pathology; D001012:Aorta, Abdominal / Q000473:pathology / Q000503:physiopathology*; D001013:Aorta, Thoracic / Q000473:pathology / Q000503:physiopathology*; D001344:Autopsy; D001696:Biomechanical Phenomena; D004547:Elastic Tissue / Q000473:pathology / Q000503:physiopathology; D004548:Elasticity; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012737:Sex Factors; D013314:Stress, Mechanical; D059289:Vascular Stiffness