Mitral regurgitation (MR) is a kind of valvular heart disease with a complicated pathogenesis. However, the current clinical understanding of MR mostly stays in a purely spatial perspective. We suggest that the evaluation of MR should break through the limited thinking of the area of a two-dimensional single frame, and transfer to a comprehensive evaluation of three-dimensional space-time integration (i.e. four-dimensional space-time). Secondly, it is of significance to pay attention to the time mechanism and time thinking of the occurrence of MR. The amount of MR may be different in different cardiac cycles or within the same cardiac cycle. Finally, changes in the time dimension of cardiac contraction can lead to the occurrence of MR and sometimes it is necessary to understand MR from time thinking rather than spatial thinking.