Right ventricular (RV) dysfunction is a common cause of heart failure in patients with congenital heart defects and often leads to impaired functional capacity and premature death. The current surgical approach, which includes pulmonary valve replacement/insertion (PVR), has yielded mixed results. MRI-based patient-specific RV/LV/Patch combination models which included fluid-structure interactions (FSI), anisotropic material properties and two-layer construction with fiber orientations were introduced to test the hypothesis that a PVR surgical design with a smaller patch and more aggressive scar tissue trimming would lead to improved RV cardiac function recovery.??Results from our models validated by pre-operation data indicated that the small patch design had 10% improvement in RV function as measured by RV ejection fraction, compared to the conventional patch.??Maximum Stress-P1 value from the anisotropic model was 149.6% higher than that from the isotropic model.???Computational RV volume predictions agreed well with CMR-measured volume data (error <3%).