Complex endovascular aortic aneurysm repair

Abstract

The use of EVAR in the management of complex aneurysms has expanded in recent years. For the purpose of this review, the term ‘complex aneurysm’ refers to aneurysms of the upper abdominal aorta that involve any combination of its visceral branches such as renal, superior mesenteric or coeliac vessels and, therefore, will mostly cover repair of juxta-renal and Type IV thoracoabdominal aneurysms. The advantages of endovascular techniques over the equivalent open repair include a reduction in blood loss and avoidance of the associated complications of laparotomy and aortic cross clamping. Although the long-term benefits are still under investigation, many vascular specialists believe that, due to rapidly advancing technology and increasing worldwide experience, it is likely that endovascular techniques will become a routine treatment option for patients with complex aneurysms. Improvements in three-dimensional thinslice CT imaging and fluoroscopy techniques, low-profile delivery systems that can negotiate tortuous iliac arteries, and the development of percutaneous techniques have further enhanced endovascular aneurysm repair. With such rapid technological advances and increasing operator experience, vascular specialists are taking on the challenge of managing complex aneurysms using endovascular techniques. The experience and ability to maintain perfusion to aortic branches and hence treat aneurysms involving the aortic arch, descending thoracic, peri-renal and iliac arteries is gathering pace. These advances have broadened the spectrum of patients who are eligible for intervention. Randomized trials have clearly demonstrated a reproducible benefit in terms of in-hospital mortality and morbidity after standard EVAR when compared with open repair. 2 Results pertaining to the endovascular repair of complex aneurysms are encouraging; however, there are no published randomized trials in ‘complex aneurysm’ repair and this treatment option therefore remains confined to the specialized vascular unit.