Invited Commentary

Abstract

Transient or permanent neurologic deficits remain the major cause of morbidity and mortality after complex aortic arch reconstruction. Neuroprotective strategies during aortic arch surgery include hypothermic arrest (HCA) alone, HCA in conjunction with retrograde cerebral perfusion (RCP), or antegrade cerebral perfusion (ACP), moderate hypothermia with ACP, and even normothermic complete arch replacement without circulatory arrest. The ideal method of arterial cannulation and cerebral and systemic protection remain undefined. Several reports document the safety and efficacy of these various approaches. However, large clinical series and laboratory data have suggested several limitations of RCP in aortic arch surgery. Svensson and colleagues [1Svensson L.G. Nadolny E.M. Penney D.L. et al.Prospective randomized neurocognitive and S-100 study of hypothermic circulatory arrest, retrograde brain perfusion, and antegrade brain perfusion for aortic arch operations.Ann Thorac Surg. 2001; 71: 1905-1912Abstract Full Text Full Text PDF PubMed Scopus (108) Google Scholar] have documented that the brain is incompletely perfused when using RCP. Okita and colleagues [2Okita Y. Minatoya K. Tagusari O. et al.Prospective comparative study of brain protection in total aortic arch replacement: deep hypothermic circulatory arrest with retrograde cerebral perfusion or selective antegrade cerebral perfusion.Ann Thorac Surg. 2001; 72: 72-79Abstract Full Text Full Text PDF PubMed Scopus (203) Google Scholar] found that the prevalence of transient neurologic dysfunction was significantly higher using RCP when compared with ACP. A recent survey of major aortic centers found 50% preferred selective ACP, 38% used a combination of techniques, and 6% used both HCA and RCP [3Stein L.H. Elefteriades J.A. Protecting the brain during aortic surgery: an enduring debate with unanswered questions.J Cardiothorac Vasc Anesth. 2009 July 29; ([Epub ahead of print])Google Scholar]. Numerous arterial perfusion techniques have been described that allow ACP during aortic arch surgery. These techniques include selective cannulation of the ostium of the innominate artery (IA) or left carotid artery (or both of these arteries), cannulation of the axillary artery, cannulation of the innominate artery, and construction of an arch first graft. Huang and colleagues [4Huang F.J. Wu Q. Ren C.W. et al.Cannulation of the innominate artery with a side graft in arch surgery.Ann Thorac Surg. 2010; 89: 800-804Abstract Full Text Full Text PDF PubMed Scopus (26) Google Scholar] have described a method of innominate artery perfusion using an 8-mm vascular graft in conjunction with the use of HCA for aortic arch surgery. The majority of patients in this series had type A dissections (34 of 46 patients), 4 patients required surgery for type B dissection, and the remainder had aneurysmal disease of the ascending aorta and arch. The operative mortality rate for this complex set of patients was a respectable 6.5%. Interestingly, there were no reported neurologic complications of either transient or permanent neurologic dysfunction. Although the methods and techniques used by Huang and colleagues [4Huang F.J. Wu Q. Ren C.W. et al.Cannulation of the innominate artery with a side graft in arch surgery.Ann Thorac Surg. 2010; 89: 800-804Abstract Full Text Full Text PDF PubMed Scopus (26) Google Scholar] have largely been described elsewhere for ACP during aortic arch surgery, the novel idea of attaching a side-arm graft to the innominate artery is unique. The authors suggest that a side-arm graft is preferential to direct cannulation for the following reasons: less risk of damage to the innominate artery, less requirement for manipulation of a cannula, and less risk of stenosis of the IA after tying down the pursestring sutures after de-cannulation. Perhaps these reasons are based more on surgeon preference, as many centers report excellent results with direct cannulation. Indeed, the main benefit of direct IA perfusion is the rapidity in which it may be accomplished in an urgent or emergent situation, which requires aortic arch reconstruction (ie, dissection surgery). In addition, the use of a side-biting clamp, as the authors describe, may be more traumatic to the IA than direct cannulation. Therefore, a side-arm graft may be an over complicated method for ACP for most patients. The authors did illustrate one example in which a side-arm graft would be necessary (ie, those patients with small IA diameters). The authors should be commended on their early series of a unique method to supply ACP during complex aortic arch reconstruction. The absence of any neurologic complications is remarkable in this challenging patient population, and the authors' work contributes to the expanding experience of refining aortic arch surgery. Cannulation of the Innominate Artery With a Side Graft in Arch SurgeryThe Annals of Thoracic SurgeryVol. 89Issue 3PreviewThe purpose of this study was to examine the safety and efficacy of cannulation of the innominate artery with a side graft in arch surgery. Full-Text PDF