The following research, conducted by Borowski F., Kaule S., and colleagues concerns a type of heart valve that can be inserted without open-heart surgery (transcatheter aortic valve replacement TAVR). The researchers wanted to see if the way the valve is inserted affects how well blood flows through it, specifically the risk of thrombosis, or blood clot formation, due to misalignment of the artificial valve. To perform the study an experimental artificial model of the human heart was created after which they then inserted the valve in two different ways, measuring the flow field with particle image velocimetry (PIV).
To evaluate the risk of thrombosis two fluid mechanic predictors where chosen, shear induced effect and residence time, which are commonly associated with the thrombosis formation. These two transport equations were calculated and solved using the numerical solvers provided by FEATool Multiphysics. Geometry and time dependent boundary conditions in the fluid domain could be implemented using the measured PIV velocity fields, using custom MATLAB functions in FEATool, after which a transient numerical simulation was performed to solve the transport equations.
The results of the study show that the circumferential positioning of TAVR has an impact on the local flow field. The authors conclude that the implantation strategy of a TAVR should not only focus on implantation height with respect to regurgitation but also on the alignment of native and prosthetic commissures.
FEATool’s easy to use GUI, and integration with a MATLAB programming and scripting API allowed for easy manipulation and analysis of the imported PIV data, streamlining the process of CFD simulation. Once FEATool completed the simulations, the researchers extracted the velocity and pressure data at each grid point. This data was then preprocessed and formatted and analyzed.
See the linked references for more detailed information about this research.
References
- Borowski F., Kaule S., et al. Analysis of thrombosis risk of commissural misaligned transcatheter aortic valve prostheses using particle image velocimetry, Technisches Messen, vol. 91, no. 6, pp. 291-304, 2024, doi: 10.1515/teme-2022-0100.