M-mode echocardiographic failure to consistently identify the equally bicuspid aortic valve: correlation with orifice-view aortography.

The M-mode echocardiogram is considered a satisfactory diagnostic tool for the determination of the presence of a bicuspid aortic valve. M-mode echocardiographic failure to determine this condition is occasionally encountered and has been suggested to be due to the anatomic configuration wherein the two aortic valve leaflets are nearly equal in size. By employing a specific angiographic study (orifice-view aortography), it has been shown that accurate identification of aortic valve anatomy is possible. Ten patients having orifice-view aortographic findings of an aortic valve having two essentially equally sized leaflets have been studied both by this technique and M-mode echocardiography. Five of these had M-mode echographic evidence of a bicuspid aortic valve. However, 3 exhibited no criteria diagnostic of a bicuspid valve and 2 had only suggestive criteria. The results confirm that M-mode echocardiography alone is insufficient to determine reproducibly the presence of an aortic valvular malformation with or without stenosis when the anatomy is that of an equally bicuspid aortic valve.