Fate of descending aorta after acute type A aortic dissection repair.

Background: Reports on the residual descending aortic dissection (AD) after acute type A AD (TAAD) repair has been limited. Therefore, we evaluated the fate of descending aorta in patients who underwent acute TAAD repair.

Methods: We reviewed 299 patients (mean: 60.4 years, 51.5% male) patients who received acute TAAD repair between 2009 and 2018, except genetic aortopathy and concomitant surgeries for the descending aorta. Subjects are categorized into classic TAAD (Classic, n=226), retrograde extension of TAAD from the intimal tear in the descending aorta (Retro, n=31), and intramural hematoma (IMH, n=42) types of AD. Interested outcome was expansion rate of descending aorta. Secondary outcome was descending aorta events including surgical repair, interventions, and aortic rupture. To reduce selection bias, baseline variables were adjusted. Multivariable risk analyses were performed to find risk factors of the study outcomes.

Results: In crude analysis, descending aorta in Retro [beta, 2.260; standard error (SE), 0.559] and Classic (beta, 1.542; SE, 0.233) groups expanded faster than IMH (beta, 0.443; SE, 0.491) group. Unadjusted risk of aortic event was significantly higher in the Retro group compared with the IMH [hazard ratio (HR) =4.80; 95% confidence interval (CI): 1.56-14.7] and Classic (HR =2.36; 95% CI: 1.24-4.49) groups. Baseline adjustment did not alter these findings. In multivariable analyses, the presence of intimal tear in the upper thoracic descending aorta (above 7th thoracic vertebra) was significantly associated with the aortic expansion (beta, 2.06; SE, 0.61) and events (HR =8.74; 95% CI: 4.34-17.6).

Conclusions: The descending aorta growth was faster in Retro and Classic than IMH and related with the tear location. Careful assessment on the descending is warranted.