Dynamic analysis of flutter in disk type mechanical heart valve prostheses

Area of Science:

• Biomedical Engineering
• Cardiovascular Research
• Computational Fluid Dynamics

Background:

• Prosthetic heart valves (PHV) can exhibit low-frequency oscillations.
• Understanding these oscillations is crucial for patient outcomes and device design.

Purpose of the Study:

• To parametrically study low-frequency oscillations in disc-type prosthetic heart valves (PHV).
• To determine the frequencies of dynamic fluttering using computational methods.
• To investigate the cause of clinically observed leaflet oscillations.

Main Methods:

• Finite element analysis was employed.
• The "ANSYS" computer program was utilized for dynamic fluttering frequency determination.
• Parametric variations of occluder geometry were considered.

Main Results:

• Calculated dynamic fluttering frequencies were significantly higher (by at least two orders of magnitude) than in vivo observations.
• Both circular and semi-circular occluder designs showed high flutter frequencies.
• The findings suggest dynamic flutter is not the primary cause of clinical oscillations.

Conclusions:

• Clinically observed prosthetic heart valve oscillations are unlikely to be caused by dynamic flutter.
• Vortex shedding is proposed as the more probable mechanism driving these in vivo oscillations.
• Further research into fluid-structure interaction and vortex shedding in PHVs is warranted.