Aneurysms and dissections of aortic arch and thoracoabdominal aorta: Single centre experience with hybrid treatment

Aim. In the last decade, several "off-label" indications for thoracic endovascular aortic repair (TEVAR), have modified the way that most surgeons approach thoracic aortic disease. Among these is the so-called hybrid (open and endo) repair. Methods. From 1998 through 2012, 231 aortic arch repairs and 467 thoraco-abdominal aortic repairs were performed at our centre. From 2001 we categorized, according to Ishimaru's classification, a total of 167 aortic arch aneurysms (66.5% atherosclerotic and 33.5% dissecting) as zone 0 (48), zone 1 (37), or zone 2 (82) and, according to Crawford's classification, a total of 52 thoraco-abdominal aortic aneurysms (57% atherosclerotic and 43% dissecting) as type I (20), type II (six), type III (10), type IV (six) or aneurysms of the visceral aortic patch (10) who underwent hybrid repair by means of aortic arch / visceral aortic debranching followed by TEVAR. The most of these patients were selected for hybrid repair having increased surgical risk defined as age > 75 yrs, and/or EF < 20%, and/or FEV1<50%, and/or severe unbeatable CAD. Results. In the group of aortic arch pathologies, the initial clinical success rate was 84.3% (zone 0), 85.3% (zone 1), and 90.9% (zone 2). The 30-day mortality rate was 8.3% (zone 0), 2.7% (zone 1), and 2.4% (zone 2). Zone 0 deaths were associated with intraoperative stroke in three cases and to an aortic rupture for an acute retrograde dissection in one case. In the group of thoracoabdominal aortic pathologies, no intraoperative deaths were observed, and the technical success rate was 97.9%. Two patients died in the interprocedural period. We recorded a perioperative mortality rate of 14.9% (including deaths from multiple-organ failure, respiratory failure, and coagulopathy) and a perioperative morbidity rate of 31.9% (including morbidity from paraplegia, renal failure, respiratory failure, and pancreatitis). At a median follow-up of 21.5 months, 1 patient died from visceral graft occlusion; there were 3 type II endoleaks and 1 incident of endograft migration, none of which resulted in death. Seven patients died as a consequence of unrelated events. Hybrid repair, by avoiding thoracotomy, is particularly advantageous in high risk patients, especially, who have had previous thoracic surgery with reduced respiratory function. Furthermore, by its avoidance of thoracic aortic cross-clamping and extracorporeal circulation, has an advantage in elderly patients with poor cardiac function and valvulopathy. However, both in treatment of aneurysms and dissections, several controversial issues are still under debate. Among these, are the ideal timing between aortic debranching and TEVAR, the patency and safety of debranching grafts in the long term, the durability of aortic arch endografts, and the risks of stent-graft induced new entry tears and retrograde dissection, especially in the treatment of dissecting aneurysms. Conclusion. In selected patients with aortic arch disease, early and midterm outcomes of hybrid repair are promising and might have practical implications for the ongoing evolution of hybrid repair as well as for eventual application to patients who are fit for traditional surgery. Conversely, the complications typical of thoracoabdominal open surgery have not been reduced by hybrid repair, so the mortality and morbidity rates remain substantial. At present, hybrid repair of thoracoabdominal aortic aneurysm is, at our center, no more than an alternative to simple observation in patients who are unsuited for conventional open repair, he occurrence of aortic dissection did not negatively affect the overall outcomes of our series of hybrid repair in either group.