Biomechanics of Aortic Dissection: A Comparison of Aortas Associated With Bicuspid and Tricuspid Aortic Valves
Background Current methods for aortic dissection risk assessment are inadequate for patients with ascending aortic aneurysms associated with either bicuspid aortic valves (BAVs) or tricuspid aortic valves (TAVs). Biomechanical testing of aortic tissue may provide novel insights and biomarkers. Metho...
| Main Authors: | , , , , , , , |
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| Format: | Article |
| Language: | English |
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Wiley
2020-08-01
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| Series: | Journal of the American Heart Association: Cardiovascular and Cerebrovascular Disease |
| Subjects: | |
| Online Access: | https://www.ahajournals.org/doi/10.1161/JAHA.120.016715 |
| _version_ | 1811332368038887424 |
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| author | Jennifer C.‐Y. Chung Edwin Wong Mingyi Tang Daniella Eliathamby Thomas L. Forbes Jagdish Butany Craig A. Simmons Maral Ouzounian |
| author_facet | Jennifer C.‐Y. Chung Edwin Wong Mingyi Tang Daniella Eliathamby Thomas L. Forbes Jagdish Butany Craig A. Simmons Maral Ouzounian |
| author_sort | Jennifer C.‐Y. Chung |
| collection | DOAJ |
| description | Background Current methods for aortic dissection risk assessment are inadequate for patients with ascending aortic aneurysms associated with either bicuspid aortic valves (BAVs) or tricuspid aortic valves (TAVs). Biomechanical testing of aortic tissue may provide novel insights and biomarkers. Methods and Results From March 2017 to August 2019, aneurysmal ascending aortas (BAV=23, TAV=23) were collected from elective aortic surgery, normal aortas from transplant donors (n=9), and dissected aortas from surgery for aortic dissection (n=7). These aortas underwent delamination testing in simulation of aortic dissection. Biaxial tensile testing was performed to determine modulus of elasticity (aortic stiffness), and energy loss (a measure of efficiency in performing the Windkessel function). Delamination strength (Sd) was lowest in dissected aortas (18±6 mN/mm) and highest in normal aortas (58±16 mN/mm), and aneurysms fell in between, with greater Sd in the BAV group (37±10 mN/mm) than the TAV group (27±10 mN/mm) (P<0.001). Bicuspid aortopathy was associated with greater stiffness (P<0.001), while aneurysms with TAV demonstrated greater energy loss (P<0.001). Sd decreased by 7.8±1.2 mmol/L per mm per decade of life (r2=0.45, P<0.001), and it was significantly lower for patients with hypertension (P=0.001). Sd decreased by 6.1±2.1 mmol/L per mm with each centimeter increase in aortic diameter (r2=0.15, P=0.007). Increased energy loss was associated with decreased Sd (r2=0.41), whereas there was no relationship between Sd and aortic stiffness. Conclusions Aneurysms with BAV had higher Sd than those with TAV, suggesting that BAV was protective. Energy loss was lower in aneurysms with BAV, and inversely associated with Sd, representing a potential novel biomarker. |
| first_indexed | 2024-04-13T16:35:49Z |
| format | Article |
| id | doaj.art-054d897dedf2403e9e34ba264fc5b993 |
| institution | Directory Open Access Journal |
| issn | 2047-9980 |
| language | English |
| last_indexed | 2024-04-13T16:35:49Z |
| publishDate | 2020-08-01 |
| publisher | Wiley |
| record_format | Article |
| series | Journal of the American Heart Association: Cardiovascular and Cerebrovascular Disease |
| spelling | doaj.art-054d897dedf2403e9e34ba264fc5b9932022-12-22T02:39:25ZengWileyJournal of the American Heart Association: Cardiovascular and Cerebrovascular Disease2047-99802020-08-0191510.1161/JAHA.120.016715Biomechanics of Aortic Dissection: A Comparison of Aortas Associated With Bicuspid and Tricuspid Aortic ValvesJennifer C.‐Y. Chung0Edwin Wong1Mingyi Tang2Daniella Eliathamby3Thomas L. Forbes4Jagdish Butany5Craig A. Simmons6Maral Ouzounian7Division of Cardiovascular Surgery University Health Network Toronto ON CanadaDepartment of Mechanical and Industrial Engineering University of Toronto Toronto ON CanadaDepartment of Mechanical and Industrial Engineering University of Toronto Toronto ON CanadaDivision of Cardiovascular Surgery University Health Network Toronto ON CanadaDivision of Vascular Surgery University Health Network Toronto ON CanadaDepartment of Pathology University Health Network Toronto ON CanadaDepartment of Mechanical and Industrial Engineering University of Toronto Toronto ON CanadaDivision of Cardiovascular Surgery University Health Network Toronto ON CanadaBackground Current methods for aortic dissection risk assessment are inadequate for patients with ascending aortic aneurysms associated with either bicuspid aortic valves (BAVs) or tricuspid aortic valves (TAVs). Biomechanical testing of aortic tissue may provide novel insights and biomarkers. Methods and Results From March 2017 to August 2019, aneurysmal ascending aortas (BAV=23, TAV=23) were collected from elective aortic surgery, normal aortas from transplant donors (n=9), and dissected aortas from surgery for aortic dissection (n=7). These aortas underwent delamination testing in simulation of aortic dissection. Biaxial tensile testing was performed to determine modulus of elasticity (aortic stiffness), and energy loss (a measure of efficiency in performing the Windkessel function). Delamination strength (Sd) was lowest in dissected aortas (18±6 mN/mm) and highest in normal aortas (58±16 mN/mm), and aneurysms fell in between, with greater Sd in the BAV group (37±10 mN/mm) than the TAV group (27±10 mN/mm) (P<0.001). Bicuspid aortopathy was associated with greater stiffness (P<0.001), while aneurysms with TAV demonstrated greater energy loss (P<0.001). Sd decreased by 7.8±1.2 mmol/L per mm per decade of life (r2=0.45, P<0.001), and it was significantly lower for patients with hypertension (P=0.001). Sd decreased by 6.1±2.1 mmol/L per mm with each centimeter increase in aortic diameter (r2=0.15, P=0.007). Increased energy loss was associated with decreased Sd (r2=0.41), whereas there was no relationship between Sd and aortic stiffness. Conclusions Aneurysms with BAV had higher Sd than those with TAV, suggesting that BAV was protective. Energy loss was lower in aneurysms with BAV, and inversely associated with Sd, representing a potential novel biomarker.https://www.ahajournals.org/doi/10.1161/JAHA.120.016715aortic aneurysmaortic dissectionbicuspid aortic valvebiomechanics |
| spellingShingle | Jennifer C.‐Y. Chung Edwin Wong Mingyi Tang Daniella Eliathamby Thomas L. Forbes Jagdish Butany Craig A. Simmons Maral Ouzounian Biomechanics of Aortic Dissection: A Comparison of Aortas Associated With Bicuspid and Tricuspid Aortic Valves Journal of the American Heart Association: Cardiovascular and Cerebrovascular Disease aortic aneurysm aortic dissection bicuspid aortic valve biomechanics |
| title | Biomechanics of Aortic Dissection: A Comparison of Aortas Associated With Bicuspid and Tricuspid Aortic Valves |
| title_full | Biomechanics of Aortic Dissection: A Comparison of Aortas Associated With Bicuspid and Tricuspid Aortic Valves |
| title_fullStr | Biomechanics of Aortic Dissection: A Comparison of Aortas Associated With Bicuspid and Tricuspid Aortic Valves |
| title_full_unstemmed | Biomechanics of Aortic Dissection: A Comparison of Aortas Associated With Bicuspid and Tricuspid Aortic Valves |
| title_short | Biomechanics of Aortic Dissection: A Comparison of Aortas Associated With Bicuspid and Tricuspid Aortic Valves |
| title_sort | biomechanics of aortic dissection a comparison of aortas associated with bicuspid and tricuspid aortic valves |
| topic | aortic aneurysm aortic dissection bicuspid aortic valve biomechanics |
| url | https://www.ahajournals.org/doi/10.1161/JAHA.120.016715 |
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