ASSESSMENT OF MITRAL REGURGITATION SEVERITY BY DOPPLER COLOR-FLOW MAPPING OF THE VENA CONTRACTA

Background Although Doppler color flow mapping is widely used to asses s the severity of mitral regurgitation (MR), a simple, accurate, and q uantitative marker of MR by color flow mapping remains elusive. We hyp othesized that vena contracta width by color flow mapping would accura tely predict the severity of MR.Methods and Results We studied 80 pati ents with MR. Vena contracta width was measured in multiple views with zoom mode and nonstandard angulation to optimize its visualization. F low volumes across the left ventricular outflow tract and mitral annul us were calculated by pulsed-Doppler technique to determine regurgitan t volume. Effective regurgitant orifice area was calculated by dividin g the regurgitant volume by the continuous-wave Doppler velocity-time integral of the MR jet. The cause of MR was ischemia in 24, dilated ca rdiomyopathy in 34, mitral valve prolapse in 12, endocarditis in 2, rh eumatic disease in 2, mitral annular calcification in 1, and uncertain in 5. Regurgitant volumes ranged from 2 to 191 mL. Regurgitant orific e area ranged from 0.01 to 1.47 cm(2). Single-plane vena contracta wid th from the parasternal long-axis view correlated well with regurgitan t volume (r=.85, SEE=20 mL) and regurgitant orifice area (r=.86, SEE=0 .15 cm(2)). Biplane vena contracta width from apical views correlated well with regurgitant volume (r=.85, SEE=19 mL) and regurgitant orific e area (r=.88, SEE=0.14 cm(2)). A biplane vena contracta width greater than or equal to 0.5 cm was always associated with a regurgitant volu me >60 mL and a regurgitant orifice area >0.4 cm(2). A biplane vena co ntracta width less than or equal to 0.3 cm predicted a regurgitant vol ume <60 mL and a regurgitant orifice area <0.4 cm(2) in 24 of 29 patie nts. No other parameter, including jet area, left atrial size, pulmona ry flow reversal, or semiquantitative MR grade, correlated significant ly with regurgitant volume or regurgitant orifice area in a multivaria te analysis. Conclusions Our results demonstrate that careful color fl ow mapping of the vena contracta of the MR jet provides a simple quant itative assessment of MR that correlates well with quantitative Dopple r techniques.