# 4D-Flow MRI Characterization of Pulmonary Flow in Repaired Tetralogy of Fallot
## 3 Results
\begin{table}
\begin{tabular}{l c c c} \hline \hline  & **MPA Diameter** & \begin{tabular}{c} **Pulmonary Valve Peak** \\ **Velocity** \\ **(r, p-Value)** \\ \end{tabular} & \
\begin{tabular}{c} **Pulmonary Valve** \\ **Velocity** \\ **(r, p-Value)** \\ \end{tabular} &
\begin{tabular}{c} **Pulmonary Valve** \\ **Regurgitant Fraction (r, p-Value)** \\ \end{tabular} \\ \hline RVOT Peak Velocity & 0.520, 0.002 & 0.474, 0.003 & 0.478, 0.003 \\ RVOT Regurgitant Fraction & 0.480, 0.005 & 0.487, 0.002 & 0.787, 0.001 \\ Pulmonary Valve Peak Velocity & 0.544, 0.001 & - & 0.316, 0.056 \\ Pulmonary Valve Regurgitant Fraction & 0.497, 0.004 & 0.316, 0.056 & - \\ MPA Peak Velocity & 0.564, 0.001 & 0.886, 0.001 & 0.310, 0.062 \\ MPA Regurgitant Fraction & 0.661, 0.001 & 0.520, 0.001 & 0.724, 0.001 \\ Pre-bifurcation Peak Velocity & 0.495, 0.004 & 0.898, 0.001 & 0.263, 0.116 \\ Pre-bifurcation Regurgitant Fraction & 0.624, 0.001 & 0.522, 0.001 & 0.862, 0.001 \\ RPA Peak Velocity & 0.181, 0.322 & 0.520, 0.001 & 0.288, 0.084 \\ RPA Regurgitant Fraction & 0.423, 0.016 & 0.448, 0.005 & 0.844, 0.001 \\ LPA Peak Velocity & 0.287, 0.111 & 0.673, 0.001 & 0.407, 0.012 \\ LPA Regurgitant Fraction & 0.679, 0.001 & 0.454, 0.005 & 0.873, 0.001 \\ RVOT Average WSS & 0.262, 0.147 & 0.230, 0.170 & 0.330, 0.046 \\ Pulmonary Valve Average WSS & 0.395, 0.025 & 0.361, 0.028 & 0.478, 0.003 \\ MPA Average WSS & 0.224, 0.218 & 0.475, 0.003 & 0.316, 0.057 \\ Pre-bifurcation Average WSS & 0.377, 0.033 & 0.617, 0.001 & 0.426, 0.009 \\ RPA Average WSS & 0.260, 0.150 & 0.550, 0.001 & 0.288, 0.084 \\ LPA Average WSS & 0.310, 0.084 & 0.726, 0.001 & 0.558, 0.001 \\ Pre-bifurcation Maximum WSS & 0.180, 0.325 & 0.405, 0.013 & 0.190, 0.260 \\ RPA Maximum WSS & 0.074, 0.689 & 0.522, 0.001 & 0.357, 0.030 \\ LPA Maximum WSS & 0.117, 0.522 & 0.384, 0.019 & 0.051, 0.763 \\ RVOT Average axial WSS & 0.340, 0.057 & 0.340, 0.039 & 0.570, 0.001 \\ Pulmonary Valve Average axial WSS & 0.364, 0.040 & 0.511, 0.001 & 0.506, 0.001 \\ MPA Average axial WSS & 0.421, 0.016 & 0.724, 0.001 & 0.492, 0.003 \\ Pre-bifurcation Average axial WSS & 0.401, 0.023 & 0.672, 0.001 & 0.593, 0.001 \\ RPA Average axial WSS & 0.409, 0.020 & 0.769, 0.001 & 0.485, 0.002 \\ LPA Average axial WSS & 0.395, 0.025 & 0.755, 0.001 & 0.228, 0.174 \\ RVOT Average circumferential WSS & 0.362, 0.042 & 0.732, 0.001 & 0.377, 0.021 \\ Pulmonary Valve Average circumferential WSS & 0.634, 0.001 & 0.870, 0.001 & 0.492, 0.002 \\ MPA Average circumferential WSS & 0.524, 0.002 & 0.725, 0.001 & 0.264, 0.114 \\ Pre-bifurcation Average circumferential WSS & 0.662, 0.001 & 0.639, 0.001 & 0.392, 0.016 \\ RPA Average circumferential WSS & 0.367, 0.039 & 0.744, 0.001 & 0.403, 0.013 \\ LPA Average circumferential WSS & 0.584, 0.001 & 0.725, 0.001 & 0.521, 0.001 \\ \hline \hline \end{tabular}  
* PA: Pulmonary Artery; RVOT: Right Ventric Outflow Tract; MPA: Main Pulmonary Artery; RPA: Right Pulmonary Artery; LPA: Left Pulmonary Artery; WSS: Wall Shear Stress.  
\end{table} 
Table 4: Correlations with main pulmonary artery diameter, pulmonary valve peak velocity, and regurgitant fraction. Figure 8: Pressure drops along the pulmonary artery. Pulmonary valve, main pulmonary artery (MPA), pre-bifurcation, right pulmonary artery (RPA), and left pulmonary artery (LPA). The right ventricular outflow tract was used as the reference plane location. Panel (**A**) shows the assessment of maximum pressure drop (PD). Panel (**B**) shows the average PD. * indicates _p_-value \(\leq\) 0.05 between rTOF patients and controls. ** indicates _p_-value \(\leq\) 0.001 between rTOF patients and controls. Maximum EL was found significantly higher in the rTOF as compared to the controls along the PA (2.49 \(\pm\) 0.23 mW vs. 0.37 \(\pm\) 0.23 mW, \(p\) < 0.001). Most significant losses were observed at the pulmonary valve and bifurcation regions. The average EL was also found to be higher in the rTOF patients in comparison to controls (0.90 \(\pm\) 0.11 mW vs. 0.15 \(\pm\) 0.11 mW, \(p\) < 0.001).