Background: For patients with complicated acute thoracic aortic syndromes, endovascular treatment, when feasible, is preferred over open surgery. However, there are limited data on the long-term benefits of endovascular treatment in complicated acute aortic syndromes affecting the descending thoracic aorta. Hypothesis: The endovascular treatment is expected to have more favorable long-term mortality and fewer late reintervention in complicated acute thoracic aortic syndromes. Methods: Of 155 consecutive patients with acute aortic syndromes, 94 met the inclusion criteria of the study; 63 underwent endovascular repair (group 1) and 31 underwent open repair (group 2). Patients with a diagnosis of acute aortic syndrome localized in the descending thoracic aorta distal to the emergence of the left subclavian artery, complicated by rupture, malperfusion syndrome, and/or acute aortic expansion, were included. Indications for repair of the descending thoracic aorta included impending rupture in 70.2%, malperfusion syndrome in 29.8%, and persistence of pain with aortic expansion (aortic diameter >40 mm) in 2 patients. Results: During the follow-up period (63.0 ± 24.6 months), the cumulative survival free from cardiovascular death rates at 5 years was 92.0% and 51.4% in group 1 and 2, respectively (log rank P = 0.0001). Late mortality related to the aorta was 1.6% with thoracic endovascular aortic repair and 0% with surgical treatment. Conclusions: Endovascular treatment in patients with complicated acute thoracic aortic syndromes localized at the descending thoracic aorta is feasible and safe, with a lower rate of early complications and similar long-term benefits when compared with surgical treatment.