In this zoom view of the mitral valve, we see the valve with and without color flow doppler. In this case, the regurgitant flow occupies the entire left atrium, which is not enlarged, suggesting a relatively new onset of regurgitation. The prolapse of the posterior leaflet results in a jet directed towards the interatrial septum where the flow circulates in the atrium. This amount of MR also resulted in reversal of pulmonary venous flow.