Retrospectively triggered Cine MRI achieved up to 80 frames per cardiac cycle in 25 minutes, proving superior to interleaved electrocardiography-triggered protocols for assessing murine diastolic function.
Does retrospectively triggered Cine MRI improve the assessment of left ventricular diastolic function in mice compared to electrocardiography-triggered Cine MRI?
A retrospectively triggered Cine MRI protocol enables high frame rate imaging in mice, allowing for accurate assessment of subtle left ventricular diastolic dysfunction.
To assess left ventricular (LV) diastolic function in mice with Cine MRI, a high frame rate (>60 frames per cardiac cycle) is required. For conventional electrocardiography-triggered Cine MRI, the frame rate is inversely proportional to the pulse repetition time (TR). However, TR cannot be lowered at will to increase the frame rate because of gradient hardware, spatial resolution, and signal-to-noise limitations. To overcome these limitations associated with electrocardiography-triggered Cine MRI, in this paper, we introduce a retrospectively triggered Cine MRI protocol capable of producing high-resolution high frame rate Cine MRI of the mouse heart for addressing left ventricular diastolic function. Simulations were performed to investigate the influence of MRI sequence parameters and the k-space filling trajectory in relation to the desired number of frames per cardiac cycle. An optimized protocol was applied in vivo and compared with electrocardiography-triggered Cine for which a high-frame rate could only be achieved by several interleaved acquisitions. Retrospective high frame rate Cine MRI proved superior to the interleaved electrocardiography-triggered protocols. High spatial-resolution Cine movies with frames rates up to 80 frames per cardiac cycle were obtained in 25 min. Analysis of left ventricular filling rate curves allowed accurate determination of early and late filling rates and revealed subtle impairments in left ventricular diastolic function of diabetic mice in comparison with nondiabetic mice.
Coolen et al. (Thu,) conducted a other in Left ventricular diastolic function in mice. Retrospectively triggered Cine MRI protocol vs. Electrocardiography-triggered Cine MRI was evaluated on Left ventricular filling rate curves (early and late filling rates). Retrospectively triggered Cine MRI achieved up to 80 frames per cardiac cycle in 25 minutes, proving superior to interleaved electrocardiography-triggered protocols for assessing murine diastolic function.