Residual flow in false lumen of chronic descending aortic dissection

A 58-year-old male patient has a history of a Stanford type A aortic dissection running up to the left common iliac artery for which a composite aortic valve graft replacement was performed approximately three years ago. This time, the patient presented with fever and chills. We performed a transesophageal echocardiography (TEE), which excluded vegetations. Upon retracting the TEE probe, the descending aorta showed two compartments (Fig. 1a) separated by a dissected intimal layer (Fig. 1a, arrow heads); the largest compartment is the false lumen (Fig. 1a, hash). Colour Doppler imaging showed laminar flow through the true aortic lumen (Fig. 1a, asterisk). In the false aortic lumen, slow rotating blood flow existed (online video). This phenomenon was not present more proximally in the descending aorta at the aortic arch (Fig. 1b). Residual blood flow may persist in the false lumen years after aortic dissection because of multiple fenestrations in the dissected intimal layer providing entry and exit locations for blood flow. In approximately 70% of patients with acute type A aortic dissection, the dissection extends beyond the ascending aorta [1–3]. After repair, these patients show an increased risk of developing postdissection aortic aneurysm mainly through false lumen di-