In Patients with a Retrograde Type A Aortic Dissection, Does Treatment Like a Type B Aortic Dissection Improve Outcomes?

Abstract

Type A aortic dissection is a surgical emergency with mortality approaching 60 % when treated with medical therapy alone. Survival benefit has been consistently demonstrated with emergent surgical repair; however, overall mortality is still reported to be as high as 25 %. Type A aortic dissection most commonly arises from a primary intimal tear just distal to the coronary ostia, followed by primary aortic arch tear. Less commonly, retrograde type A dissection (RTAD) can arise from a primary intimal tear in the descending aorta with retrograde propagation into the ascending aorta. RTAD are categorized as spontaneous or iatrogenic. Spontaneous RTAD account for approximately 10 % of all acute type A dissections. Iatrogenic RTAD have become a topic of increased interest due to their occurrence after thoracic endovascular aortic repair (TEVAR) for type B descending thoracic aortic (DTA) dissections and aneurysms. In addition, open surgical repair of RTAD carries increased perioperative morbidity and mortality due to the necessity of replacing the aortic arch in order to cover the primary dissection flap. Some clinicians have advocated treating RTAD in a similar fashion to type B dissection where the mainstay of treatment is medical management with or without TEVAR. Studies comparing medical and surgical therapies have demonstrated improved medium term outcomes RTAD compared to antegrade dissections. The studies suggest that medical management may be suitable in select patients who have (1) no malperfusion syndromes, (2) false lumen thrombosis, (3) no aneurysmal disease, and (4) no rupture. No long term data is available comparing retrograde versus antegrade aortic dissection, thus, the true natural history is unclear. In this report, we review the current literature on the management strategies of RTAD and provide our institutional approach in treating this complex aortic pathology