3DE assessment of the LV in a patient with transposition of great artery post-Mustard repair. (A) 3D volume rendering of the subpulmonary LV, systemic RV, and AV valves from ventricular perspective demonstrating semilunar shape of the LV cavity. (B) Flexi-slice display of subpulmonary LV demonstrating significant difference in LV diameters when 3D volume is being cropped from different echocardiographic planes. (C) 3D surface rendering of the subpulmonary LV and final result of volumetric analysis. Note the compressed semilunar shape of the LV with concave interventricular septum.