Editorial Comment: The Borst elephant trunk technique is not lethal!

Abstract

The paper by Kondoh et al. [1] describes the results of total arch replacement with a long elephant trunk ending at the level of T6–T8. This technical modification simultaneously differs to, and matches, the classic Borst technique, or a variations of, in a number of ways. What are the similarities? First, the portion of the prosthesis, the trunk, extending into the descending aorta is non-stented and free floating. The length of the trunk is longer than in the classic elephant trunk technique, where it is generally limited to only 5–10 cm (although it has always been a matter of debate as to what the ideal trunk length should be). What are the differences? The proximal anastomosis of the elephant trunk is now located in the distal ascending aorta at the origin of the innominate artery leaving the arch untouched and even unopened. This makes it possible to arrest body circulation only for a brief time period (25 min). The distal end of the elephant trunk is located at the level of T6–T8. Kondoh’s technique also differs from the frozen elephant trunk technique in that the trunk diameter is undersized rather than oversized and, of course, non-stented. In dissection patients it is introduced in the true lumen and the false lumen is not obliterated anymore as in the frozen elephant trunk technique. The fixation of the trunk is also located more proximally. The body arrest temperatures (25°C) are lower than contemporary series, which have described their results with the frozen elephant trunk. Antegrade selective cerebral perfusion is used as in every total arch replacement perfusing both axillary arteries and the left common carotid artery to protect the brain. What could be the advantages of this new technique? The body arrest time is short, all anastomoses can be reached easily, making it obvious that no patient required a re-exploration for bleeding. In-hospital mortality (9 of 127, 7%) is acceptable but not extremely low. What could be the disadvantages? There are still 3.2% spinal cord injuries which is comparable with the frozen elephant trunk but substantially higher than in the classic elephant trunk technique. In-hospital mortality of the second stage is rather high (2 of 12, 16%). As in thoracic endografting, it is understandable that the longer the graft, the higher the risk of paraplegia. During follow-up, there are a high number of aorto-enteric fistulizations, a well-known and almost lethal complication after the frozen elephant trunk but something that has almost never been described after the classic elephant trunk. It is important to stress that, despite the undersizing of the diameter of the graft, the authors found a thromboexclusion in the majority (86%) of the patients treated. This number is even higher than in the frozen elephant trunk. Apparently aortic arch aneurysms extending into the descending thoracic aorta for various lengths, but not below the diaphragm, can nowadays be treated surgically by a multitude of different alternatives. Roughly speaking, one can prefer a one-step approach to a two-step procedure. Of course, the one-step approach offers the advantage of solving the problem in one operation and is theoretically devoted with a morbidity and mortality that is limited to this single procedure. The two-step approach offers the advantage that the repair can be extended below the diaphragm if necessary, but obviously includes a substantial dual risk. In recent years, endovascular techniques, be they pure or hybrid procedures, have been added to the surgical armamentarium, making choices not only more numerous but also more difficult. The question is no longer can we solve the problem, it is rather a matter of choosing the best strategy taking into account patient-, surgeon-, procedureand hospital-related factors. The authors advocating this new technique cannot convince me with this new approach. We are making hardly any progress. On the contrary, I believe that we have rather taken a step back: more paraplegia and paraparesis, more fistulizations in the long run, a high mortality rate, taking into account both steps. The wave of frozen elephant trunks that has overwhelmed us in the last few years and has been embraced by a lot of surgeons as the ultimate solution, has apparently not resulted in better results. The total arch replacement, herein described, with the long elephant trunk has not either. So, clearly, the classic elephant trunk technique is not so bad still, and is not lethal. New techniques come and go, but they will only stay if their results exceed those of previously established procedures. This critical comment does not mean that the authors should not be congratulated for their courage in creating a modification