Effect of false lumen partial thrombosis on repaired acute type A aortic dissection

Objective: Studies on the partial thrombosis of a false lumen after repairing a type A acute aortic dissection (TAAAD) have reported conflicting results. We investigated the effects of a partially thrombosed false lumen on the segmental growth rates, distal aortic reoperations, and long-term survival. Methods: The postoperative computed tomography scans of 67 patients were retrospectively reviewed. A false lumen was independently defined at 3 segments of the descending thoracic aorta (DTA) on the last follow-up computed tomography scan: the proximal segment near the aortic arch, the distal segment near the diaphragm, and the middle segment. Results: The segmental aortic growth rate of completely thrombosed, completely patent, and partially thrombosed false lumens was -0.10 +/- 0.31, 0.09 +/- 0.22, and 0.35 +/- 0.60 mm/mo at the proximal DTA (P = .001), -0.04 +/- 0.18, 0.12 +/- 0.19, and 0.28 +/- 0.28 mm/mo at the middle DTA (P < .001), and -0.02 +/- 0.13, 0.07 +/- 0.07, and 0.16 +/- 0.14 mm/mo at the distal DTA (P < .001), respectively. The corresponding freedom from reoperation rates for the proximal DTA at 10 years were 100%, 88%, and 62% (P = .013). The overall 10-year survival rate was 89% and was not significantly different among the study groups. Conclusions: Partial thrombosis at each segment of a residual false lumen after TAAAD repair correlated with a faster regional aortic growth rate and predicted a greater reoperation rate but did not affect long-term overall survival.