Evaluating isovelocity surface area flow convergence method with finite element modeling.

C G DeGroff; A M Baptista; D J Sahn

doi:10.1016/s0894-7317(98)70056-2

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PubMed · 9719093

Evaluating isovelocity surface area flow convergence method with finite element modeling.

C G DeGroff·A M Baptista·D J Sahn

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Abstract

Through numerical experimentation we investigated the isovelocity surface area flow convergence method used in estimating regurgitant valve flow rates. Recent advances in three-dimensional color Doppler flow imaging have created renewed interest in this method. Experimentation was based on the use of depth-averaged finite element models of the left heart. The heart models studied varied from "synthetic" representations to a model of a left heart traced from an actual echocardiographic image of a patient with a prolapsed mitral valve. The isovelocity surface area flow convergence method overestimated regurgitant flow rates throughout the Nyquist limits considered with a critical Nyquist limit in which this overestimation is minimized. The angle dependence of Doppler color flow imaging partially corrects for this overestimation. The isovelocity surface area flow convergence method is a viable alternative to methods currently in use. Through numerical experimentation, we have begun to shed light on the inaccuracies inherent in this flow convergence method.

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Blood Flow Velocity Computer Simulation Coronary Circulation Echocardiography, Doppler, Color Echocardiography, Three-Dimensional Humans Mitral Valve Insufficiency Models, Cardiovascular Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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C G DeGroff, A M Baptista, D J Sahn. 1998. Evaluating isovelocity surface area flow convergence method with finite element modeling.. https://doi.org/10.1016/s0894-7317(98)70056-2

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