Clinical Application Of The Color Doppler Flow Convergence Method In Calculating Aortic Effective Regurgitant Orifice Area

Objective To investigate the clinical usefulness of color Doppler flow convergence(FC) method in the quantification of aortic regurgitation, use the FC and the conventional Doppler echocardiography (DE) methods to calculate the effective regurgitant orifice area (ERO). Method 48 patients with isolated aortic regurgitation owning a flat proximal flow convergence angle have been chosen to involve in the research, of whom, 35 are male, 13 female, aging between 22 and 78, with average age of 56±6.5. Out of the 48 patients, 23 subjects suffer from valve retrogression, 9 subjects aortic bicuspid deformation, 7 subjects slight aortic prolapsus, 6 subjects pure aortic base expansion, and 3 subjects other reasons. The color FC method and conventional DE method are adopted respectively to calculate the effective regurgitant orifice area (ERO). Result Of the 48 subjects, the radius of the first aliasing area during diastole (r), the instant flow velocity of the first aliasing area (Vr), the biggest flow velocity of the aortic regurgitation during the diastole (VAr), and the time-velocity integration of aortic regurgitation (TVIar) are, respectively, (0.72±0.21)cm, (28.4±9.7)cm/s, (458.6±42.7)cm/s, and (238.3±47)cm. The effective regurgitant orifice area (ERO) obtained by color FC and the convention DE are (0.32±0.17)cm2 and (0.33±0.16)cm2 respectively (P>0.05). There exists an excellent correlation between the two methods (y =0.99x-0.01, r=0.97,P<0.0001). Conclusion The FC method which can be used to measure the ERO with reasonable feasibility in aortic regurgitation with a flat proximal flow convergence angle, provides a reliable approach to quantify aortic regurgitation.