[The flow convergence method in the quantitative assessment of valvular regurgitation by real-time tri-plane...

This paper is aimed to evaluate the accuracy and influence factors about quantitative assessment of valve regurgitation using flow convergence (FC) method with real-time tri-plane echocardiography. By an in vitro model made by ourselves we observed the areas of the FC of the regurgitant orifice under different diameters with the real-time tri-plane echocardiography. The effective regurgitant orifice areas (EROA) and the flow rate were calculated under different pressure gradients, instrument gain and color Doppler surveying range. The results were compared with the real size of the regurgitation orifice and flow rate. In 4mm, 6mm, and 8mm diameter of the regurgitant orifice, the instrument gain and color Doppler surveying rage have not significant influence on the measurement result of flow rate (P = 0.384, P = 0.903). But the measurement result of flow rate was increased following the pressure gradient augment (P = 0.00). While in the regurgitant orifice with diameter 2mm the measurement result of flow rate was influenced by the instrument gain but was not influenced by the pressure gradient or color Doppler surveying range (P = 0.55, P = 0.39). The measurement result of EROA was correlated well with the real regurgitant orifice area (r = 0.99). Using FC method with real-time tri-plane echocardiography to quantitatively assess the valvular regurgitation is simple and feasible. But it should be noted that the pressure gradient and diameter of regurgitant orifice have shown their influence on the results.