Schematic of fused BAV phenotypes as seen by parasternal short-axis transthoracic echocardiography. Applicable to similar tomographic views by cardiac computed tomography and cardiac magnetic resonance, the figure demonstrates the 3 fused BAV phenotypes as zoomed views of the base of the heart (black square) for anatomical landmark correlation. Note that all fused BAVs have 3 distinguishable aortic sinuses. Note the oval (American football shape) systolic opening of these 3 valves as opposed to the triangular opening of a tricuspid aortic valve. (1) Right–left cusp fusion (most common) with visible raphe, 2 different size/shape functional cusps [the non-fused cusp (non-coronary) is commonly of larger ‘compensatory’ size than the others]. (2) Right non-cusp fusion with visible raphe, 2 different size/shape functional cusps [the non-fused cusp (left) is larger than the others]. (3) Left non-cusp fusion with a visible raphe (least common), 2 different size/shape functional cusps [the non-fused cusp (right) is larger than the others]. It is important to note that these short-axis imaging views do not correspond to the surgeon’s intraoperative view. Note how, in diastole, the commissural angle of the non-fused cusp of these 3 asymmetrical BAVs is <170–180° (see Fig. 9); in systole, the right–left commissures are at 10 and 4 o’clock (1: yellow arrows), right non-commissures at 1 and 7 o’clock (2: yellow arrows) and left-non-commissures at 2 and 8 o’clock (3: yellow arrows) (see Fig. 7). These 3 fused phenotypes may not have a visible raphe and may also have symmetrical non-fused cusp angle (see Fig. 8). BAV: bicuspid aortic valve; IAS: interatrial septum; LC: left cusp; NC: non-coronary cusp; RC: right cusp; RV: right ventricle; TV: tricuspid valve. Modified from Michelena et al. [10] with permission from Elsevier.