Please use this identifier to cite or link to this item:
https://observatorio.fm.usp.br/handle/OPI/22462
Title: | Biomechanical failure properties and microstructural content of ruptured and unruptured abdominal aortic aneurysms |
Authors: | RAGHAVAN, Madhavan L.; HANAOKA, Mauro M.; KRATZBERG, Jarin A.; HIGUCHI, Maria de Lourdes; SILVA, Erasmo Simao da |
Citation: | JOURNAL OF BIOMECHANICS, v.44, n.13, p.2501-2507, 2011 |
Abstract: | Purpose: To test the hypothesis that ruptured abdominal aortic aneurysms (AAA) are globally weaker than unruptured ones. Methods: Four ruptured and seven unruptured AAA specimens were harvested whole from fresh cadavers during autopsies performed over an 18-month period. Multiple regionally distributed longitudinally oriented rectangular strips were cut from each AAA specimen for a total of 77 specimen strips. Strips were subjected to uniaxial extension until failure. Sections from approximately the strongest and weakest specimen strips were studied histologically and histochemically. From the load-extension data, failure tension, failure stress and failure strain were calculated. Rupture site characteristics such as location, arc length of rupture and orientation of rupture were also documented. Results: The failure tension, a measure of the tissue mechanical caliber was remarkably similar between ruptured and unruptured AAA (group mean +/- standard deviation of within-subject means: 11.2 +/- 2.3 versus 11.6 +/- 3.6 N/cin; p=0.866 by mixed model ANOVA). In post-hoc analysis, there was little difference between the groups in other measures of tissue mechanical caliber as well such as failure stress (95 +/- 28 versus 98 +/- 23 N/cm(2); p=0.870), failure strain (0.39 +/- 0.09 versus 0.36 +/- 0.09; p=0.705), wall thickness (1.7 +/- 0.4 versus 1.5 +/- 0.4 mm; p=0.470), and % coverage of collagen within tissue cross section (49.6 +/- 12.9% versus 60.8 +/- 9.6%; p=0.133). In the four ruptured AAA, primary rupture sites were on the lateral quadrants (two on left; one on left-posterior; one on right). Remarkably, all rupture lines had a longitudinal orientation and ranged from 1 to 6 cm in length. Conclusion: The findings are not consistent with the hypothesis that ruptured aortic aneurysms are globally weaker than unruptured ones. |
Appears in Collections: | Artigos e Materiais de Revistas Científicas - FM/MCG Artigos e Materiais de Revistas Científicas - HC/InCor Artigos e Materiais de Revistas Científicas - LIM/28 |
Files in This Item:
File | Description | Size | Format | |
---|---|---|---|---|
art_RAGHAVAN_Biomechanical_failure_properties_and_microstructural_content_of_ruptured_2011.PDF Restricted Access | publishedVersion (English) | 642.26 kB | Adobe PDF | View/Open Request a copy |
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.