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Annals of Biomedical Engineering

, Volume 47, Issue 1, pp 97–112 | Cite as

A Non-Invasive Material Characterization Framework for Bioprosthetic Heart Valves

  • Mostafa Abbasi
  • Mohammed S. Barakat
  • Danny Dvir
  • Ali N. AzadaniEmail author
Article
  • 343 Downloads

Abstract

Computational modeling and simulation has become more common in design and development of bioprosthetic heart valves. To have a reliable computational model, considering accurate mechanical properties of biological soft tissue is one of the most important steps. The goal of this study was to present a non-invasive material characterization framework to determine mechanical propertied of soft tissue employed in bioprosthetic heart valves. Using integrated experimental methods (i.e., digital image correlation measurements and hemodynamic testing in a pulse duplicator system) and numerical methods (i.e., finite element modeling and optimization), three-dimensional anisotropic mechanical properties of leaflets used in two commercially available transcatheter aortic valves (i.e., Edwards SAPIEN 3 and Medtronic CoreValve) were characterized and compared to that of a commonly used and well-examined surgical bioprosthesis (i.e., Carpentier-Edwards PERIMOUNT Magna aortic heart valve). The results of the simulations showed that the highest stress value during one cardiac cycle was at the peak of systole in the three bioprostheses. In addition, in the diastole, the peak of maximum in-plane principal stress was 0.98, 0.96, and 2.95 MPa for the PERIMOUNT Magna, CoreValve, and SAPIEN 3, respectively. Considering leaflet stress distributions, there might be a difference in the long-term durability of different TAV models.

Keywords

Inverse finite element simulation Bioprosthetic heart valves Three-dimensional anisotropic mechanical properties Optimization Fung constitutive model Holzapfel–Gasser–Ogden constitutive model Carpentier-Edwards PERIMOUNT Magna Edwards SAPIEN 3 Medtronic CoreValve 

Notes

Acknowledgment

This work was supported partially by the American Heart Association Scientist Development Grant (AHA16SDG30920009) and by graduate scholarship from Jazan University.

Supplementary material

10439_2018_2129_MOESM1_ESM.tif (114 kb)
Supplementary material 1 Pressure curves acquired from the in vitro DIC tests (TIFF 114 kb).
10439_2018_2129_MOESM2_ESM.tif (66.4 mb)
Supplementary material 2 Pressure and flow waveforms of the three bioprosthetic heart valves obtained from in vitro testing in the pulse duplicator system (TIFF 67952 kb).
10439_2018_2129_MOESM3_ESM.tif (1.4 mb)
Supplementary material 3 Examples of degenerated bioprostheses. A, Carpentier-Edwards Perimount valve: leaflet tear. B, Carpentier-Edwards Magna Ease valve: leaflet calcification. C, Engager THV (Medtronic): leaflet restriction and calcification. D, Carpentier-Edwards Perimount valve: leaflet tear (ventricular side). Reprinted with permission from Dvir et al.15 (TIFF 1386 kb).

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Copyright information

© Biomedical Engineering Society 2018

Authors and Affiliations

  1. 1.The DU Cardiovascular Biomechanics Laboratory, Department of Mechanical and Materials EngineeringUniversity of DenverDenverUSA
  2. 2.Department of Medicine, Division of CardiologyUniversity of WashingtonSeattleUSA

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