Cg. Degroff et al., EVALUATING ISOVELOCITY SURFACE-AREA FLOW CONVERGENCE METHOD WITH FINITE-ELEMENT MODELING, Journal of the American Society of Echocardiography, 11(8), 1998, pp. 809-818
Through numerical experimentation we investigated the isovelocity surf
ace area flow convergence method used in estimating regurgitant valve
flow rates. Recent advances in three-dimensional color Doppler flow im
aging have created renewed interest in this method. Experimentation wa
s based on the use of depth-averaged finite element models of the left
heart. The heart models studied varied from ''synthetic'' representat
ions to a model of a left heart traced from an actual echocardiographi
c image of a patient with a prolapsed mitral valve. The isovelocity su
rface area flow convergence method overestimated regurgitant flow rate
s throughout the Nyquist limits considered with a critical Nyquist lim
it 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 alte
rnative to methods currently in use. Through numerical experimentation
, we have begun to shed light on the inaccuracies inherent in this flo
w convergence method.