Appraisal of power loads on elements of artificial heart valves through the results of echocardiogram processing

Conclusions

1. Analysis of echocardiograms of patients with implanted prosthetic heart valves shows that the fibrous ring (along with the valve seat attached to it) is movable, which is an important factor for the calculation of valves and the designing of test stands.

2. The velocity vectors of the fibrous ring and the ball at the moment of impact of the ball and the shell are directed opposite to each other, which demonstrates the necessity of summing their moduli in the conduct of calculations.

3. Obtaining experimental data on the dynamics of prosthetic heart valves that have been implanted into patients allows evaluation of the adequacy of test-stand trials of valves.

4. As calculations based on the analysis of the energy balance equation for all elements of the valve have shown, the value of the stress for impact of the ball with the shell (taking account of the movability of the fibrous ring) is, on the average, equal to 0.352 N; for rigid mounting, the value is 1.48 N. Therefore, testing of prosthetic valves for reliability under conditions that do not correspond to physiological conditions may lead to incorrect conclusions.