Abstract 17817: Does a Repaired Type A Dissection Turn into a Medical Type B Dissection? Lessons From IRAD
Background: Following complete arch replacement, many Type A acute aortic dissection (TAAAD) patients exhibit a residual false lumen in their descending and/or abdominal aorta. Medically-managed Type B (TBAAD) patients with descending thoracic involvement resemble these post-operative TAAAD cases. We sought to examine whether outcomes differed between these two groups with anatomically-similar remaining dissection flaps.
Methods: We analyzed 1017 patients enrolled in the International Registry of Acute Aortic Dissection. Of these, 241 (23.7%) had TAAAD with complete arch replacement; 776 (76.3%) were medically-managed TBAAD patients with most proximal extension in the descending aorta.
Results: TAAAD patients were younger (58.0 ± 13.2 v. 64.9 ± 13.7 years, p<0.001) and more often male (80.1% v. 60.3%, p<0.001). Of the 418 (45.4%) with intimal tear identified, the tear was located in the descending aorta and therefore not resected in 4.1% of TAAAD patients, versus 39.9% of their TBAAD counterparts. Additionally, Type A patients had larger descending aortic diameters on presentation (5.0 ± 6.4 v. 4.8 ± 5.3 cm, p<0.001) but smaller abdominal aortic dimensions (2.4 ± 0.6 v. 3.0 ± 1.0 cm, p<0.001). In-hospital mortality was higher in the TAAAD cohort (24.9% v. 8.9%, p<0.001). However, a Kaplan-Meier analysis of five-year mortality showed no significant difference between groups.
Conclusions: The increased in-hospital mortality of Type A patients likely reflects the higher risks and more complicated clinical course associated with surgical repair. No long-term differences in mortality were seen between groups, despite the younger age of Type A patients and lower prevalence of a prevailing intimal tear. Further studies are warranted to determine whether aortic growth or other post-discharge outcomes differ between cohorts.
- © 2013 by American Heart Association, Inc.