Invited commentary

Abstract

This is an important article about an endovascular tour de force: the development and implantation of branched endografts for complex aortoiliac anatomy. It should be clear that this is not a procedure for the faint of heart or those lacking state-of-the-art endovascular interventional skills. Even in the hands of highly skilled interventionalists who are worldwide leaders in the technique, fluoroscopy times averaged >60 minutes for the more straightforward iliac and suprarenal cases and a sobering 117 minutes for the thoracoabdominal cases. In the high-risk patient cohort for whom the procedure is desired, this minimally invasive procedure carries significant risk: of the 29 suprarenal and thoracoabdominal aneurysms, there were four aneurysm-related deaths and two cases of paraparesis and paraplegia. Thus, branched-graft endovascular aneurysm repair for thoracoabdominal aneurysms is not something that can or should be adopted by the average center in the very near future. To be sure, this report represents the learning curve of a very complex procedure performed in a difficult patient population. In the early 1990s, endovascular repair of typical infrarenal abdominal aortic aneurysms (AAAs) was challenging also, causing many to wonder whether it would ever be adopted on a wide scale. Despite this, clinical pioneers and early adopters worked with manufacturers to develop techniques and devices that work well, are applicable to most infrarenal AAAs, and produce one-third the mortality rate of open repair. Despite ongoing work to improve durability, the aneurysm-related mortality advantage for endovascular repair of conventional aneurysms persists out to 2 to 4 years in randomized, prospective trials.1Blankensteijn J. de Jong S. Prinssen M. van der Heim A. Buth J. van Sterkenburg S. Two-year outcomes after conventional or endovascular repair of abdominal aortic aneurysms.N Engl J Med. 2005; 352: 2398-2405Crossref PubMed Scopus (838) Google Scholar, 2EVAR TrialistsEndovascular aneurysm repair versus open repair in patients with abdominal aortic aneurysm (EVAR trial 1) randomised controlled trial.Lancet. 2005; 365: 2179-2186Abstract Full Text Full Text PDF PubMed Scopus (1335) Google Scholar This report by Greenberg et al is evidence that branched-endograft technology has a likely development pathway. Initially, the technology will be applied in the least challenging and least risky cases: branched endografts for maintaining internal iliac artery perfusion. In conjunction with simpler, single-vessel fenestrated endograft technology, highly experienced endovascular centers will advance their expertise further in this area by treating juxtarenal and suprarenal aortic aneurysms. As the methods and materials technology mature, branched endografts for more complex thoracoabdominal aortic aneurysms will likely expand to a relatively small number of centers in the context of clinical trials. Whether it will expand beyond that is anyone’s guess, but recent history makes it seem unwise to think that branched endograft technology will remain limited to only a handful of centers. On the other hand, the recent Endovascular Aneurysm Repair 2 (EVAR 2) trial3The EVAR TrialistsEndovascular aneurysm repair and outcome in patients unfit for open repair of abdominal aortic aneurysm (EVAR trial 2) randomised controlled trial.Lancet. 2005; 364: 2187-2192Google Scholar gives one pause to regard how broadly this technology should be applied, at least in thoracoabdominal aneurysms. Many of these high-risk patients have a relatively short life expectancy, but need to live long enough to benefit from aneurysm repair if this new procedure is to be considered. Thus, patient selection will become even more crucial in this patient cohort, where anatomic evaluation will obviously be more challenging than for conventional endografts. At least in the near term, this highly complex technology needs to be developed under the strict scrutiny of well-documented clinical trials sponsored by manufacturers or centers of expertise.