Fig. 4

Quantitative analysis (to compare with the results of analysis represented in Fig. 6), of functional mitral regurgitation by three-dimensional full-volume color Doppler transthoracic echocardiography: acute study (post-cardiac resynchronization therapy 13-day follow-up). Left: Setting cardiac resynchronization therapy OFF. Right: Setting cardiac resynchronization therapy ON with interventricular delay 0 ms. a, c Automated anatomy detection of the left ventricular endocardial border, mitral annulus, left ventricular outflow, and placement of three-dimensional hemispheric flow sampling planes in the mitral annulus (white arrow) and left ventricular outflow (yellow arrow). b, d Flow-time curve derived from automatic flow volume aggregation at each frame in the cardiac cycle and the automated calculation of the mitral (In SV), aortic (Out SV) stroke volume, regurgitant volume, regurgitation fraction (RF), and cardiac output (CO), with mean value, in three cardiac cycles, respectively. AVG mean value, CRT cardiac resynchronization therapy, F.U. follow-up, REG VOL regurgitant volume, TTE transthoracic echocardiogram, VV interventricular