Total aortic arch replacement in 2013: where do we go from here?

Abstract

In the last 10–15 years, substantial progress has been made in the surgical treatment of patients who require open repair or replacement of the aortic arch. A number of technological advances have contributed to the improved outcomes. These include better methods of brain and myocardial protection, improved cardiopulmonary bypass circuits, impregnated polyester grafts, use of biological glues, and better identification and management of coagulopathies. Enhanced understanding of the pathophysiology and limitations of hypothermic circulatory arrest has also played a major role in the improved results. Using a variety of techniques, highly satisfactory outcomes have been achieved for patients who require partial (hemi-arch) repair, which requires relatively short periods of circulatory arrest. Total arch replacement has traditionally been associated with higher risks. However, recent reports on total arch replacement from experienced centres document operative mortality rates and stroke rates <10% for both outcomes [1–6]. These studies have included, to a variable extent, patients with acute aortic dissection who required emergent operation (2.4–19% prevalence), and it is well recognized that early mortality and morbidity are increased in this subset of patients. Some form of antegrade cerebral perfusion for brain protection was used for all of the patients in these studies, and there is emerging consensus that this represents the optimal method for brain protection. Spinal-cord ischaemic injury, in the absence of extensive resection of the descending thoracic aorta, has occurred rarely. With the advent of endovascular stent-grafting of the thoracic aorta, alternative methods for management of disorders, involving the aortic arch, have been explored. Hybrid procedures have been developed that consist of transposition of the brachiocephalic arteries, followed by synchronous or metachronous stentgrafting of the aortic arch and adjacent descending thoracic aorta with either an antegrade or retrograde approach. It was hypothesized that this technique would be a safer, less-extensive procedure with less mortality and morbidity than conventional open repair and would be particularly applicable to ‘high-risk’ patients (i.e. those considered to be at substantial risk or noncandidates for open repair).