Limitations
The present study was performed at a single center and the number of subjects was small. Accordingly, the results obtained need to be confirmed in a larger number of subjects. Furthermore, it was not possible to evaluate VFM in 3D fields. Blood flow is affected by the structure of the LV. Therefore, evaluations of blood flow in 3D fields will be more precise than those in 2D fields. This is a technical limitation that will be overcome with technological advances in VFM. Another limitation was the severity of diastolic dysfunction. The results of the present study showed diastolic dysfunction may affect peak EL in ED, LD, and Sys. The grading of LV diastolic dysfunction and comparisons of peak EL in each phase may result in more detailed assessments. Therefore, the relationship between EL and the grade of diastolic dysfunction needs to be investigated in more detail in future studies. The present study also did not evaluate vortexes, which need to be assessed in each phase.