Type A Acute Aortic Dissection: Why Does the False Channel Remain Patent After Surgery?

Purpose: To understand why the false channel (FC) remains patent after surgery of type A acute aortic dissection (TAAAD). Materials and Methods: Postoperative contrast-enhanced computed tomography scans of 129 patients operated for TAAAD were analyzed, and a color-Doppler ultrasound examination (CDUS) of the supra-aortic vessels (SAVs) was performed in 12 patients. Results: The FC remained patent in 107 (82.9%) patients. The entry site was situated near the distal anastomosis in 43 (40.2%) patients and far from it in 44 (41.1%) patients. In 10 (9.35%) patients, an entry site was observed only in the SAVs. In 10 (9.35%) patients, no entry site was seen. Of the 12 patients explored with CDUS, a retrograde filling of the FC was observed in 11 patients. Conclusion: The frequent postoperative circulating aortic FC can be explained by the persistence of the primary entry tear, the presence of iatrogenic tears, and/or a retrograde filling in the SAVs.