Intracardiac cardiovascular magnetic resonance velocity mapping: comparison of k-t BLAST and SENSE accelerated 4D acquisitions with 2D-flow at 1.5 T and 3 T

Methods Cardiac 4D-flow with k-tBLAST and SENSE and nonaccelerated 2D-flow measurements of the aorta and pulmonary trunk were obtained from 7 healthy volunteers (36 ± 15 years, 5 males) in a 1.5 T and 3 T Philips MRI Scanner. Typical 4D-flow parameters for k-t BLAST were: speedup factor 5, 15 time phases, TE/TR/flip: 3.7/7.6 ms/ 8°, and for SENSE: parallel imaging factor 2, 40 time phases, TE/TR/flip: 3.7/6.3 ms/8°. The voxel size was 3 × 3 × 3 mm3. 2D-flow was acquired with a PC-FFE sequence with TE/TR/flip: 5.3/8.6 ms/15°. 2D-flow was acquired with 35 time phases and voxel size 1.2 × 1.2 × 6 mm3. The different sequences for each volunteer were acquired in a random order during a single session. From the 4D datasets, 2D-images perpendicular to the aorta and pulmonary artery were reconstructed using in-house developed software. Flow was measured by outlining the aorta and pulmonary trunk in the velocity encoded 2D-images and these contours were transferred to the reconstructed 4Dimages. Stroke volumes (SV) and flow were compared using Wilcoxon's test, linear regression and Bland-Altman analysis.