Related Experiment Video
Updated: Aug 7, 2026
11:12
Protocol for Relative Hydrodynamic Assessment of Tri-leaflet Polymer Valves
Published on: October 17, 2013
From Polymer Structure to Valve Function: A Multiscale Evaluation of Polycarbonate Polyurethanes for Polymeric Mitral
Farhad Sadeghi1, Nnaoma Agwu1, Mia Tacklind1
1Department of Biomedical Engineering, University of California, 2420 Engineering Hall, Irvine, CA, 92697-2730, USA.
Annals of Biomedical Engineering
|August 6, 2026
Summary
Polycarbonate-based polyurethanes show promise for polymeric mitral valves, maintaining function after wear testing. Material properties influence leaflet mechanics and flow, offering a framework for next-generation heart valves.
Area of Science:
- Biomaterials Science
- Cardiovascular Engineering
- Polymer Science
Background:
- Polymeric heart valves (PHVs) aim to combine mechanical durability with bioprosthetic hemodynamics.
- A key challenge is linking polymer properties to valve function.
- This study investigates polycarbonate-based polyurethanes for mitral valve scaffolds.
Purpose of the Study:
- Evaluate polycarbonate-based polyurethanes as scaffold materials for polymeric mitral valves.
- Utilize a multiscale structure-function approach to assess material properties and valve performance.
- Establish relationships between polymer characteristics and valve-level function.
Main Methods:
- Characterized two aromatic polycarbonate-based thermoplastic polyurethanes (Carbothane AC-4095A and QuadraSil ARCS 90A) using rheological, mechanical, and spectroscopic analyses.
- Fabricated and evaluated trileaflet valve scaffolds using particle image velocimetry (PIV), pressure-flow measurements, and accelerated wear testing (AWT) up to 50 million cycles.
- Assessed preliminary in vivo performance of a Carbothane valve in an ovine model.
Main Results:
- QuadraSil showed higher viscosity and better elastic recovery; Carbothane exhibited greater stiffness and tear resistance.
- Both materials maintained stable valve function, projected orifice area, and pressure waveforms after AWT.
- PIV revealed physiologic flow patterns for both valves, with material-dependent differences in vorticity. In vivo, the Carbothane valve showed preserved transmitral inflow and low gradients.
Conclusions:
- Polycarbonate-based polyurethanes demonstrate promising performance as polymeric mitral valve scaffolds.
- Material-specific properties impact leaflet mechanics and flow organization while maintaining structural integrity.
- Findings offer a multiscale framework for developing next-generation polymeric and hybrid tissue-engineered heart valves.
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