Transesophageal echocardiogram of descending aortic dissection

Aortic dissection is characterized by the formation of an "intimal flap" seen as a hyperechoic line extending across the vessel delimiting two distinct lumens (A). Color flow Doppler (B) depicts higher (orange) blood flow velocity and intraluminal velocity in the inferior of the two lumens, but does not provide definitive information regarding which is the true lumen and false lumen.