Invited commentary

Abstract

The current manuscript addresses the concept of “adequate” seal zones to treat blunt thoracic aortic injury (BTAI). All thoracic endograft devices currently available in the United States recommend a proximal seal zone of 20 mm as well as distal seal zones of 20 mm. It is well known that these devices were designed, tested, and validated for the treatment of thoracic aorta aneurysms. Conceptually, the boundary conditions to achieve endograft seal are different for aortic dissection, penetrating ulcers, saccular aneurysms, and BTAI. However, we know very little about those boundary conditions other than our collective clinical experience in treating these conditions with thoracic endovascular aortic repair. In the case of BTAI, it is foreseeable that simply covering the acute tear with 5 mm of seal may be enough to protect the patient from aortic rupture and death. The difference in 5 mm and 20 mm of seal zone may require coverage of the left subclavian artery and may advance the endograft into a landing zone with more angulation. In the current series, none of the cases that required coverage of the left subclavian artery required revascularization, although it is possible that arm malperfusion may occur later in life. Two of the seven patients with left subclavian coverage required additional endografts to treat malpositioning of the proximal stent on the lesser curvature. The authors report a 100% technical success rate for patients treated with 20 mm of proximal seal and 93% for patients with <20 mm of seal. The authors believed the reduced technical success rate was due to inadequate sizing of devices and not related to the shorter seal zone. The authors' experience adds to our knowledge of treating BTAI and demonstrated good clinical outcomes with both strategies of treatment. The decision to select a shorter seal zone for BTAI will be dictated by the surgeon's ability to adequately identify the location of the aortic tear and effectively to achieve seal in an emergent setting. For these concerns, the TRANSFIX study investigators and the Gore C-Tag trial chose a 20-mm proximal seal zone for inclusion criteria in treating BTAI.1Starnes B.W. Dwivedi A.J. Giglia J.S. Woo K. TRANSFIX Study InvestigatorsEndovascular repair for blunt thoracic aortic injury using the Zenith Alpha low-profile device.J Vasc Surg. 2015; 62: 1495-1503Abstract Full Text Full Text PDF PubMed Scopus (12) Google Scholar, 2Farber M.A. Giglia J.S. Starnes W.B. Stevens S.L. Holleman J. Chaer R. et al.TAG 08-02 clinical trial investigatorsEvaluation of the redesigned conformable GORE TAG thoracic endoprosthesis for traumatic aortic transection.J Vasc Surg. 2013; 58: 651-658Abstract Full Text Full Text PDF PubMed Scopus (34) Google Scholar Both trials yielded a 100% technical success rate, which parallels the experience in the current manuscript. Short-term results of left subclavian artery salvage in blunt thoracic aortic injury with short proximal landing zonesJournal of Vascular SurgeryVol. 68Issue 4PreviewThoracic endovascular aortic repair (TEVAR) is the standard treatment of blunt thoracic aortic injury (BTAI). The concept of seal was derived from the treatment of aneurysms and has been adopted for BTAI. Given the location of injury in BTAI, left subclavian artery (LSA) coverage is sometimes necessary. In these often healthier aortas, a shorter proximal landing zone may be acceptable and beneficial in avoiding some complications. Current practice patterns vary, and long-term effects of LSA coverage remain unknown. Full-Text PDF Open Archive