Total arch replacement with an open stent graft for acute type A aortic dissection: fate of the false lumen.

Objective: To describe the fate of the false lumen remaining in the descending thoracic aorta after extensive primary repair of the thoracic aorta by the modified elephant trunk technique with a stent graft for acute type A aortic dissection, particularly the changes of the false lumen on enhanced CT scanning.

Methods: The subjects were 65 consecutive patients who received arch replacement with an open stent graft for type A acute aortic dissection. CT scanning was performed at 1, 3, 12, 36, and 60 months postoperatively to detect thrombus formation, absorption of thrombus, and obliteration of the false lumen after its exclusion by the stent graft. The aorta was measured at four levels, which were the distal border of the stent graft, the middle and distal parts of the descending thoracic aorta, and the origin of the superior mesenteric artery.

Results: Obliteration was recognized in all patients at the distal border of the stent graft and absorption of thrombus was seen in 90% at the middle of the descending thoracic aorta within 1 year after surgery. However, the false lumen remained patent at the superior mesenteric artery (SMA) level in 50% of the patients.

Conclusions: In patients with acute type A aortic dissection, it is possible to perform extensive primary repair of the thoracic aorta with relative safety by stent grafting, and this method may reduce the necessity for further operations to manage a residual false lumen.