Impact of Pressure Recovery in the Evaluation of the Omnicarbon™ Tilting Disc Valve

Abstract

Background: Pressure recovery is not taken into account when calculating transprosthetic gradients after mechanical valve replacement using Doppler echocardiography. This may lead to underestimation of valvular performance. Methods: Simultaneous measurement of Doppler and direct transprosthetic gradients was performed in a circulatory mock loop simulator with physiologic parameters at different heart rates and cardiac outputs for small-sized aortic Omnicarbon™ tilting disc valves (19 - 21 mm). Results: In all adjustments the Doppler gradient significantly overestimated the net transvalvular gradient. The amount of pressure recovery averaged 59.3 %. Conclusions: Doppler echocardiography does not allow for pressure recovery, which is a significant phenomenon in the hemodynamic function of the Omnicarbon™ tilting disc valve. Valve performance is much better than expected from Doppler gradients.

Key words

Transvalvular gradient - pressure recovery - Omnicarbon™ valve

References

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