Impact of pulmonary artery flow distribution on Fontan hemodynamics and flow energetics

Figures

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  Fig. 1. Flow distribution measurement. The IVC and SVC emitter volumes (purple and green, respectively) as well as manually placed analysis planes are shown in (a). Black arrows indicate the direction of flow within the total cavopulmonary connection. Pathlines at two progressive time points are shown in (b)–(c). Patient shown was 16 year-old male, status post extracardiac Fontan. Native anatomy included double outlet right ventricle and pulmonary valve atresia. Images depict segmentations derived from a phase contrast angiogram calculated from 4D flow MRI

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  Fig. 2. Voxel-wise analysis pipeline. Centerlines are automatically calculated (a), and planes are placed to denote the regions of interest (b). Example quantitative maps for all metrics are shown in (c)–(g). Patient shown was 20-year-old male, status-post lateral tunnel Fontan. Native anatomy included double outlet right ventricle and mitral atresia. Coronal magnitude images from 4D flow MRI are shown. EL, energy loss

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  Fig. 3. Flow distribution from the IVC (a) and SVC (b) for all 10 patients at baseline and follow-up. Gray box indicates region of equal flow distribution and dashed line marks exactly equal flow distribution. FD, flow distribution; BL, baseline; FU, follow-up

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  Fig. 4. Voxel-wise hemodynamics. ΔPeak velocity (a), ΔKinetic energy (b), Δmean energy loss (c), and Δtotal energy loss (d) stratified by baseline flow distribution (FD) from the IVC (unequal vs equal, n = 5 in each group). Patients with unequal flow distribution at baseline tended to show larger increases in all 3 metrics in the IVC. FD, flow distribution; BL, baseline; FU, follow-up; EL, energy loss; KE, kinetic energy

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  Fig. 5. Change in EL and peak velocity in the caval veins. Linear regression relates total changes normalized to follow-up duration in total energy loss with peak velocity (a) and changes in mean energy loss with peak velocity (b) in the caval veins. Model reported included both SVC and IVC measurements. EL, energy loss