A Review of Clinical Trials and Registries in Descending Thoracic Aortic Aneurysms

Aortic disease is a significant pathology, as it represents the 12th leading cause of overall death. Aneurysms of the descending thoracic aorta pose a small but significant part of this pathology. Traditional open descending thoracic aortic aneurysm (TAA) repair continues to be performed despite relatively high morbidity and mortality rates. As endovascular therapy to treat vascular disease has evolved, a paradigm shift has occurred such that likely most isolated TAAs are now repaired with an endovascular approach. Multiple, prospective trials have been performed comparing open and endovascular TAA repair with three company sponsored trials documenting clinical equipoise. In these studies, endovascular thoracic aortic aneurysm repair (ETAR) was mostly compared with historic controls or open repair from centers of excellence. While the trials all indicate that 30-day peri-operative morbidity and mortality is lower in the ETAR group, these trials were not designed to determine which patient is best served by an open versus an endovascular approach. In addition, long-term follow-up data is limited. Registry data of patients undergoing ETAR seems to mirror that of the aforementioned clinical trials and indicates acceptable morbidity and mortality profiles when compared to published open TAA repair results. Future prospective studies focused on patient selection likely will never be performed, as most believe the benefits of ETAR outweigh the lack of long term follow up data. This review will focus on repair of TAA, specifically clinical trial and registry data comparing open and endovascular repair.