Ultrasound Registry Review (URR) MV Abnormalities and Disease Practice Test

In mitral regurgitation from leaflet prolapse, the color Doppler jet direction reflects the orientation of the regurgitant orifice created by the prolapsing leaflet. When the posterior mitral leaflet prolapses into the left atrium, the regurgitant orifice points toward the anterior aspect of the left atrium, so the high-velocity flow is directed anteriorly. Therefore an anteriorly directed MR jet is characteristic of posterior leaflet prolapse. If the anterior leaflet were prolapsing, the jet would more often be directed posteriorly toward the posterior left atrial wall.