Amanda L DiCarlo1, Justin Baraboo1,2, Patrick McCarthy3, Rishi Arora4, Rod Passman4, Philip Greenland4, Daniel C Lee1,4, Daniel Kim1,2, and Michael Markl1,2
1Radiology, Northwestern University, Chicago, IL, United States, 2Biomedical Engineering, Northwestern University, Chicago, IL, United States, 3Cardiac Surgery, Northwestern University, Chicago, IL, United States, 4Cardiology, Northwestern University, Chicago, IL, United States
1Radiology, Northwestern University, Chicago, IL, United States, 2Biomedical Engineering, Northwestern University, Chicago, IL, United States, 3Cardiac Surgery, Northwestern University, Chicago, IL, United States, 4Cardiology, Northwestern University, Chicago, IL, United States
Left atrial flow stasis and reduced peak
velocity, measured with 4D flow MRI were associated with elevated heart rate
variability in patients with atrial fibrillation.
Figure 1: A) Workflow for segmentation and registration of 4D flow
and CE-MRA data. From left to right: the LA was segmented from the 4D flow PC-MRA
and the LA and LAA were segmented from the CE-MRA. The left atria are registered
together, and the resulting transform is applied to the LA and LAA of the
CE-MRA. Flow quantifications (stasis, peak velocities) are then quantified. B)
Sample of the RR signal extracted from a continuously acquired real time phase
contrast sequence and RR histogram
Figure 3: Box plots illustrating
differences in mean stasis (top row) and peak velocity (bottom row) for the LA
(left) and LAA (right) between low (n=21) and high (n=27) heart rate
variability groups. *p<0.05
