Evaluation of Left Ventricular Diastolic Function Using 4D Flow MR Imaging

Aim: to 1) evaluate the ability of 4D flow MRI to assess left ventricular (LV) diastolic function, as compared to ultrasound (US), 2) analyse simultaneously LV filling and aortic stiffness in aging. Method: We studied 36 healthy subjects (52±18 years) who underwent MRI and US exams. A custom software was used for LV segmentation and calculation of transmitral flow-rate curves in a 4D flow MRI stack of slices located between the mitral valve and the apex and perpendicular to the LV long axis. Finally, the early (E) and late (A) flow-rate peaks were automatically detected and the E/A ratio was computed. Aortic pulse wave velocity (PWV) was also calculated from the 4D flow images. Results: A significant and high correlation was found between 4D flow and US E/A (R=0.71, p<;0.001). Besides, a higher correlation was obtained between E/A and age when using 4D flow than US (E/A vs. age: R
_4D
=-0.87, p<;0.001, R
_US
=-0.69, p<;0.001). Thanks to 4D flow MRI, simultaneous variation of aortic PWV and diastolic function with age was further illustrated. Conclusion: 4D flow MRI provided consistent LV E/A measurements in terms of comparison against reference US and associations with age. It also provided an insight into aorta/left heart coupling.