Invited Commentary

Abstract

Traditional surgical approaches for repair of the aortic arch, including hypothermic circulatory arrest, are under attack. The standard surgical paradigm for addressing complex arch pathologies is being challenged by less-invasive alternatives. The catalysts for this uprising are endovascular technologies that leave the aortic arch in tact and “exclude” the diseased aortic segment from pressurized arterial flow. This is in contradistinction to the fundamental surgical principles of “resecting” the diseased aortic arch segment and replacing it with an interposition synthetic graft. A new branch of aortic surgery has subsequently evolved, termed hybrid repair, which involves combining the advantages of open surgery with the less-invasive principles of endovascular repair. It is this marriage of contrasting principles that is challenging the tenets of established aortic disease management and treatment. The real question is whether this a marriage of convenience is doomed to failure or if this is a match made in heaven? There is some disagreement as to how to best combine surgical repair of the aortic arch with endovascular technologies. At its root, there are two different techniques that have evolved, and a new nomenclature for hybrid arch repair has been developed to facilitate appropriate classification of these different approaches [1Kouillias G.J. Wheatley G.H. State-of-the-art of hybrid arch procedures: a meta-analysis.Ann Thorac Surg. 2010; 90 (689–7)Google Scholar]. The nomenclature is based on whether the arch is resected or left intact. Type I hybrid arch repair involves standard elephant trunk repair with downstream placement of the endovascular stent-graft into the distal elephant trunk graft. Type II hybrid arch repair involves extra-anatomic revascularization of the great vessels and endovascular stent-graft exclusion of the diseased aortic arch. The article by Lee and colleagues [2Lee C.W. Beaver T.M. Klodell C.T. et al.Arch debranching versus elephant trunk procedures for hybrid repair of thoracic aortic pathologies.Ann Thorac Surg. 2011; 91: 465-471Abstract Full Text Full Text PDF PubMed Scopus (39) Google Scholar] compares the outcomes of type I hybrid arch repair versus type II hybrid arch repair. At the heart of the discussion is whether the type II approach adequately treats the aortic pathology and whether extra-anatomic revascularization of the great vessels provides adequate preservation of cerebral blood flow. In this single-center study, 21 patients underwent elephant trunk reconstruction of the aortic arch and 37 patients underwent extra-anatomic reconstruction of the great vessels. There were no differences in complication rate between either group for the first stage to the hybrid repair. During the second stage endovascular repair, the elephant trunk group had a 3-fold higher complication rate. After appropriate comparisons were made between the two groups, there were no statistical differences between the groups in terms of outcomes, but the combined length of hospital stays were statistically shorter in the type II hybrid arch repair group. In a small series study of patients, this article has confirmed that type II hybrid arch repair is a viable alternative to type I repair. Outcomes for both groups were equivalent at 12 months. Although longer-term follow-up and comparisons will be necessary, it seems that based on this study, along with others, the less-invasive type II hybrid arch repair is a safe alternative. At this point, it is possible that type II hybrid arch repair may be more appropriate in higher-risk surgical patients, although this study did not select which patients would receive type I versus type II repair, based on comorbidities. Additional studies will be needed to validate the hybrid arch repair paradigm. Arch Debranching Versus Elephant Trunk Procedures for Hybrid Repair of Thoracic Aortic PathologiesThe Annals of Thoracic SurgeryVol. 91Issue 2PreviewWe compared outcomes of arch debranching (AD) and elephant trunk (ET) techniques when used with thoracic endovascular aortic repair. Full-Text PDF