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Background: Endovascular aneurysm repair has been criticised for high rates of technical failure and secondary intervention. Second generation stent-grafts have been developed in an attempt to reduce these problems. The results of a UK multi-centre experience with a second generation device (Zenith) are presented., Methods: Data were collected retrospectively from five experienced UK vascular centres in patients undergoing endovascular aneurysm repair with the Zenith stent-graft., Results: A total of 269 patients underwent attempted aneurysm repair with the Zenith device. Median aneurysm diameter was 65 (interquartile range 52-78) mm. There were no conversions to open repair. Peri-operative mortality was 4.1% (11/269). On the initial post-operative scan, 94.1% of aneurysms were successfully excluded. During a median follow-up of 363 (interquartile range 154-720) days there were 19 secondary interventions and two aneurysm ruptures., Conclusions: Second generation endovascular stent-graft designs such as the Zenith are associated with low rates of intra-operative technical complications. Few secondary interventions have been necessary during follow-up; however, surveillance is essential to ensure they continue to perform.

Endovascular aneurysm repair (EVAR) has rapidly expanded since its introduction in the early 1990s. Early experiences were understandably associated with relatively high rates of complications including conversion to open repair. Soon, perioperative morbidity and mortality results improved but these concerns were replaced by questions over the long-term effectiveness of the endovascular method highlighted by the increasing numbers of secondary interventions and even reports of aneurysm rupture. A better understanding of the behaviour of stent-grafts in the aorta and the response of aortic aneurysms to endovascular repair has been forged by observations both in vitro and in vivo. It was only relatively recently that terms such as migration and endoleak were coined. Only now that we are beginning to fully understand the causes and consequences of such problems can further developments be made. The following paper outlines some of the concepts and discusses the controversies and challenges facing clinicians involved in endovascular aneurysm surgery today.

Introduction: Endovascular aneurysm repair (EVAR) has been suggested as a technique to improve outcome of ruptured abdominal aortic aneurysm (AAA). Whether this technique becomes an established treatment will depend, in part, on the anatomy of ruptured AAA., Methods: The anatomy of intact and ruptured AAA seen in a university department of vascular surgery over 5 years was reviewed. Aneurysm anatomy was assessed with spiral computed tomographic angiography. Suitability for EVAR was assessed from the dimensions of the proximal neck and common iliac arteries. Neck length less than 15 mm, neck width greater than 30 mm, and common iliac artery diameter greater than 22 mm were declared unsuitable for EVAR., Results: Three hundred sixty-three patients with intact AAA and 46 with ruptured AAA were identified. Larger intact aneurysms were significantly associated with longer renal artery-bifurcation distance and more complex proximal neck architecture. In this sample, patients with ruptured AAA were more likely to have larger aneurysms with shorter and narrower proximal necks. Significantly more intact aneurysms were morphologically suitable for endovascular repair compared with ruptured AAA (78% vs 43%; P <.001)., Conclusions: Ruptured AAA are less likely to be suitable for endovascular repair than are intact AAA, most probably because of larger diameter at presentation. Open repair will likely remain the treatment of choice in most patients with ruptured AAA, because of current morphologic constraints of endovascular repair.

Introduction: abdominal aortic dilatation can occur above the graft following repair of infra-renal abdominal aortic aneurysm (AAA). This study aimed to determine the incidence and possible aetiological associations of recurrent juxta-anastomotic aneurysms following open repair of AAA., Methods: the diameter of the infra-renal aorta above the graft of 135 patients who had previously undergone open AAA repair was determined using ultrasound. In those where the diameter was greater than 40 mm a CT scan was undertaken. Co-morbid and operative details were determined from the patients and their clinical notes., Results: seven patients had true juxta-anastomotic aneurysms (>40 mm) in the residual infra-renal abdominal aorta, the occurrence of which was associated with tobacco smoking and hypertension. There was no association with other co-morbid factors, surgical operative details or the development of iliac aneurysms (which occurred in 3% of patients)., Conclusions: true juxta-anastomotic aneurysms develop in the residual infra-renal neck of patients following open repair of abdominal aortic aneurysm. Tobacco smoking and hypertension are significant factors associated with the development of these aneurysms. This group of patients may warrant surveillance to prevent aneurysm rupture.

Endovascular aneurysm repair (EVAR) is a controversial technique, which remains the subject of a number of prospective randomised trials. Although questions remain regarding its long-term durability objective evidence exists which demonstrates its reduced physiological impact compared with conventional open repair. If this technique could be used in patients with ruptured abdominal aortic aneurysm (AAA) it may reduce the high peri-operative mortality. A review of the literature identified a limited experience with EVAR of ruptured AAA. Only a small number of case series with selected patients exist. The majority of patients were haemodynamically stable. However, the selective use of aortic occlusion balloons allowed successful endovascular management in a small number of unstable cases. All investigators had access to an "off the shelf" endovascular stent-graft (EVG). Per-operative mortality ranged from 9 to 45% and may reflect increasing experience and patient selection. A number of patients who underwent successful EVAR were turned down for open repair. A number of important lessons have been learned from these studies but questions remain regarding patient suitability and staffing issues. If these difficulties can be surmounted then the technique may offer an alternative to open repair.

Introduction: Endovascular aneurysm surgery (EVAR) was introduced a decade ago. Early results are promising, however, there remain concerns regarding the longer-term durability of this technique. Consequently, the national multi-centre EVAR trial has been commenced to define the role of endovascular surgery in the management of abdominal aortic aneurysm., Discussion: Successful EVAR requires accurate pre-operative assessment of aneurysm morphology. Current stent-grafts allow 60% of all infra-renal AAA to be treated. Reduced physiological stress and low peri-operative morbidity and mortality rates have been demonstrated with this technique when compared to open repair. Endoleak is an Achilles heel of EVAR, although in itself does not accurately predict outcome. First and second generation devices are estimated to have a 1% per year risk of rupture., Conclusions: Increased understanding of the issues surrounding aneurysm morphology and successful stent-grafting have allowed a major reduction of early type I endoleak. Late endoleak and graft migration remain problematic. Type I and III endoleaks are risk factors for subsequent rupture although the significance of type II endoleak remains uncertain. More robust indicators of outcome success/failure are required so that follow-up may be rationalised.

Introduction: The mortality from ruptured abdominal aortic aneurysm (AAA) remains in the region of 50% despite advances in critical care. Endovascular repair of AAA has been shown to be associated with reduced physiological stress in the elective setting. It is hypothesised that the reduced physiological stress associated with EVAR may improve the outcome in patients with ruptured AAA., Methods: A feasibility study of endovascular repair of ruptured AAA was undertaken at the University Hospital, Nottingham, U.K. between 1994 and 2000. Patients admitted with ruptured AAA were assessed by a team familiar with endovascular techniques for elective repair of AAA. After giving informed consent patients underwent spiral computed tomographic angiography (CTA) in the majority of cases. Patients were then transferred to the operating theatre for EVAR., Results: Twenty patients underwent repair of ruptured AAA. Of these 20 patients, seven were referred from another hospital. Eight patients were considered unfit for open repair. The median duration of procedure was 180 min (range 120-480) and median blood loss was 1200 ml (range 750-2000 ml). The overall peri-operative mortality was 45%. A number of intra-operative and peri-operative procedures (both open and endovascular) were required to ensure aneurysm exclusion and to deal with the complications of endovascular surgery., Conclusions: Ruptured AAA remains a particularly hazardous condition to treat. There are a number of advantages of EVAR in this condition. A number of the problems early in the experience of EVAR have been addressed, but further experience is required to demonstrate its efficacy when compared with open repair., (Copyright 2001 Harcourt Publishers Limited.)