Transoesophageal echocardiographic measurement of the commissural angle of the non-fused cusp prior to valve repair. Applicable to similar tomographic views obtained using cardiac computed tomography and cardiac magnetic resonance, after careful visualization of the systolic and diastolic motion (Video 6) of this regurgitant fused-type right–left cusp fusion bicuspid aortic valve, the non-fused commissures are identified, and a line is drawn from the position of the commissures to the centre of the valve in diastole (left). The angle of the non-fused cusp (N) is then carefully measured at approximately 162° on the protractor to the right, suggesting a good chance for repair. Modified from Michelena et al. [6] with permission from Elsevier.