What is the direction of the mitral regurgitant jet in this video clip?

The color Doppler jet in the apical four-chamber view is directed posteriorly toward the posterior left atrial wall, indicating a posteriorly directed mitral regurgitant jet.

Jet direction can provide insight into the mechanism of mitral regurgitation; for example, anterior leaflet prolapse often causes a posteriorly directed jet.

This analysis is outlined in the "Textbook of Clinical Echocardiography, 6e", Chapter on Mitral Regurgitation - Jet Direction and Mechanism【20:390-395†Textbook of Clinical Echocardiography】.