An investigation of how specimen dimensions affect biaxial mechanical characterizations with cellscale biotester and constitutive modeling of porcine tricuspid valve leaflets

Laurence, Devin W.; Wang, Shuodao; Xiao, Rui; Qian, Jin; Mir, Arshid; Burkhart, Harold M.; Holzapfel, Gerhard A.; Lee, Chung-Hao

Affiliations

¹Biomechanics and Biomaterials Design Laboratory, The University of Oklahoma, USA

²School of Mechanical and Aerospace Engineering, Oklahoma State University, USA

³Department of Engineering Mechanics, Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province, Zhejiang University, Hangzhou 310027, China

⁴Department of Pediatrics, University of Oklahoma Health Sciences Center, USA

⁵Department of Surgery, University of Oklahoma Health Sciences Center, USA

⁶Institute of Biomechanics, Graz University of Technology, Austria

⁷Department of Structural Engineering, Norwegian University of Science and Technology, Norway

⁸Institute for Biomedical Engineering, Science and Technology, The University of Oklahoma, USA

⁹Department of Bioengineering, The University of California, Riverside, USA

¹⁰Present Affiliation: Division of Pediatric Cardiology, Children’s Hospital of Philadelphia, USA

Abstract and keywords

Biaxial mechanical characterizations are the accepted approach to determine the mechanical response of many biological soft tissues. Although several computational and experimental studies have examined how experimental factors (e.g., clamped vs. suture mounting) affect the acquired tissue mechanical behavior, little is known about the role of specimen dimensions in data acquisition and the subsequent modeling. In this study, we combined our established mechanical characterization framework with an iterative size-reduction protocol to test the hypothesis that specimen dimensions affect the observed mechanical behavior of biaxial characterizations. Our findings indicated that there were non-significant differences in the peak equibiaxial stretches of tricuspid valve leaflets across four specimen dimensions ranging from 4.5 × 4.5 mm to 9 × 9 mm. Further analyses revealed that there were significant differences in the low-tensile modulus of the circumferential tissue direction. These differences resulted in significantly different constitutive model parameters for the Tong–Fung model between different specimen dimensions of the posterior and septal leaflets. Overall, our findings demonstrate that specimen dimensions play an important role in experimental characterizations, but not necessarily in constitutive modeling of soft tissue mechanical behavior during biaxial testing with the commercial CellScale BioTester.

Keywords: Biaxial tensile testing; Heart valve leaflet; Specimen dimension; Constitutive modeling

Links

DOI: 10.1016/j.jbiomech.2023.111829

PubMed: 37826955

WoS: 001099292500001

History

Accepted: 2023-10-3

Online: 2023-10-5

Cited Works (1)

Year	Entry
2006	Gasser TC, Ogden RW, Holzapfel GA. Hyperelastic modelling of arterial layers with distributed collagen fibre orientations. J R Soc Interface. February 22, 2006;3(6):15-35.