Shear Stress Quantification in Tissue Engineering Bioreactor Heart Valves: A Computational Approach

Area of Science:

• Biomaterials Science
• Cardiovascular Engineering
• Tissue Engineering

Background:

• Tissue-engineered heart valves offer regenerative potential over traditional prostheses.
• Cellular maturation in engineered valves requires specific bioreactor conditions.
• Mechanical forces, like wall shear stress (WSS), are critical for tissue development but poorly understood in engineered valves.

Purpose of the Study:

• To quantify wall shear stress (WSS) in tissue-engineered heart valve scaffolds.
• To investigate the impact of varying bioreactor flow rates and valve geometries on WSS.
• To provide data for optimizing bioreactor conditions for engineered heart valve development.

Main Methods:

• Fluid-structure interaction (FSI) simulations were used to determine valve opening dynamics during systole.
• Computational fluid dynamics (CFD) simulations with refined near-wall meshing analyzed WSS.
• Simulations were performed across a range of bioreactor flow rates and valve configurations.

Main Results:

• WSS distribution, peak, and median values were characterized for different flow rates and valve geometries.
• Higher WSS magnitudes were observed in the upper region of the valve near the commissures.
• Data provided histograms and regression curves detailing WSS characteristics.

Conclusions:

• Bioreactor flow conditions significantly influence WSS experienced by engineered heart valve tissue.
• Understanding WSS patterns, particularly higher magnitudes near commissures, is vital for guiding tissue development and scaffold design.
• This study provides essential quantitative data for optimizing bioreactor environments to promote functional tissue-engineered heart valve maturation.