Best surgical option for thoracoabdominal aneurysm repair - the open approach.

Abstract

Open thoracoabdominal aneurysm (TAAA) repair is a complex surgical procedure that requires efficient replacement of diseased aorta, limitation of ischemia to the various and multiple vascular beds, and intraoperative protection of the heart, central nervous system and abdominal viscera in a patient population with multiple comorbidities. Techniques of TAAA repair have evolved from the original “clamp and sew” technique to modern perfusion-assisted techniques with varying degrees of hypothermia. In experienced aortic centers, the morbidity and mortality of TAAA repair is quite good with mortality 5.0% to 8.0%, paralysis 2.3% to 3.8%, and renal failure requiring hemodialysis 1.5% to 5.6%. Open repair is durable and the long-term survival is well-defined and acceptable. In our hands, the 10 year survival of open descending thoracic and thoracoabdominal aneurysm repair is 53.5%. The applicability of open TAAA repair to the myriad of aortic pathologies, anatomy and connective tissue disorders (CTDs) is unlimited. Thoracic endovascular aortic repair (TEVAR) is a less invasive method for repairing descending thoracic and thoracoabdominal aneurysms. Currently, the approved indication is repair of descending thoracic atherosclerotic aneurysms with adequate proximal and distal landing zones, although these devices are used to treat all aortic pathologies. The applicability of TEVAR to the transverse arch and visceral abdominal aorta has been extended using extraanatomical bypasses (hybrid techniques) or branched and/or fenestrated devices. Long-term durability of these repairs extended beyond the descending thoracic aorta is unknown. Furthermore, the application of TEVAR in patients with CTDs is not recommended in the STS guidelines for thoracic and thoracoabdominal aneurysm repair. As the next generation of devices become available (some with FDA indications other than atherosclerotic descending thoracic aneurysm) and as more data accumulates regarding the long-term efficacy of TEVAR, we may gain more insight into the specific clinical scenarios in which TEVAR may be superior to open repair. Currently, we believe that open repair in the hands of experienced surgeons is superior to TEVAR for thoracoabdominal aneurysms in a variety of aortic pathologies including: chronic aortic dissection, aortic aneurysm or dissection in patients with CTDs, mycotic pseudoaneurysm and infected aortic grafts. TEVAR has distinct advantages in other aortic pathologies, including acute complicated type B aortic dissection, blunt traumatic aortic injury (BTAI) and anatomically suitable ruptured descending thoracic aneurysm. Intimate knowledge of and facility in applying both techniques is paramount in deciding how to intervene in specific patient scenarios. The remainder of this commentary will discuss our opinion on open vs. endovascular repair of specific pathologies of the thoracoabdominal aorta.