Figure 1:  Linear method for the measurement of aortic override, as viewed from the left ventricle. The crest of the muscular ventricular septum was taken as the boundary for the aortic leaflets supported by the ventricular structures (red stars). The proportion of the circumference of the aortic root supported by the left ventricle is the sum of the red dashed lines and that supported by the right ventricle is the yellow dashed line.