Implementing Models for Mechanical Circulatory Support Presurgical Assessment in Congenital Heart Disease Treatment

To assess if a 3D printed cardiac model improves visualization of VAD and cannula placement sites in CHD-HF patients as compared to 2D imaging. The investigators will prospectively enroll CHD-HF patients at multiple centers and randomize to group A (3D printed models will be used for pre-VAD planning) or Group B (controls).