The UK EndoVascular Aneurysm Repair (EVAR) trials: randomised trials of EVAR versus standard therapy

Predicting aortic complications after endovascular aneurysm repair

Background

Lifelong surveillance is standard after endovascular repair of abdominal aortic aneurysm (EVAR), but remains costly, heterogeneous and poorly calibrated. This study aimed to develop and validate a scoring system for aortic complications after EVAR, informing rationalized surveillance.

Methods

Patients undergoing EVAR at two centres were studied from 2004 to 2010. Preoperative morphology was quantified using three-dimensional computed tomography according to a validated protocol, by investigators blinded to outcomes. Proportional hazards modelling was used to identify factors predicting aortic complications at the first centre, and thereby derive a risk score. Sidak tests between risk quartiles dichotomized patients to low- or high-risk groups. Aortic complications were reported by Kaplan–Meier analysis and risk groups were compared by log rank test. External validation was by comparison of aortic complications between risk groups at the second centre.

Results

Some 761 patients, with a median age of 75 (interquartile range 70–80) years, underwent EVAR. Median follow-up was 36 (range 11–94) months. Physiological variables were not associated with aortic complications. A morphological risk score incorporating maximum aneurysm diameter (P < 0·001) and largest common iliac diameter (measured 10 mm from the internal iliac origin; P = 0·004) allocated 75 per cent of patients to a low-risk group, with excellent discrimination between 5-year rates of aortic complication in low- and high-risk groups at both centres (centre 1: 12 versus 31 per cent, P < 0·001; centre 2: 12 versus 45 per cent, P = 0·002).

Conclusion

The risk score uses commonly available morphological data to stratify the rate of complications after EVAR. The proposals for rationalized surveillance could provide clinical and economic benefits.

Abdominal aortic aneurysms: endovascular options and outcomes - proliferating therapy, but effective?

Abdominal aortic aneurysm (AAA) has a reported prevalence rate of 1.4% in the US. AAA rupture accounts for an estimated 15,000 deaths per year, rendering it the 10th leading cause of death in men over the age of 55. Endovascular repair (EVR) has proliferated in the last two decades as an increasingly popular alternative to traditional open surgery, and is now the default treatment in the majority of centres worldwide. This review article outlines the evidence supporting this stance. The development of EVR is reviewed, alongside trends in utilisation of this therapy over time. The evidence for the relative short-term and long-term outcomes of EVR and open AAA repair is discussed, and ongoing controversies surrounding the use of EVR are considered.

Ten-year results of endovascular abdominal aortic aneurysm repair from a large multicenter registry

OBJECTIVE

To assess outcomes after endovascular abdominal aortic aneurysm repair (EVAR) in an integrated health care system.

METHODS

Between 2000 and 2010, 1736 patients underwent EVAR at 17 centers. Demographic data, comorbidities, and outcomes of interest were collected. EVAR in patients presenting with ruptured or symptomatic aneurysms was categorized as urgent; otherwise, it was considered elective. Primary outcomes were mortality and aneurysm-related mortality (ARM). Secondary outcomes were change in aneurysm sac size, endoleak status, major adverse events, and reintervention.

RESULTS

Overall, the median age was 76 years (interquartile range, 70-81 years), 86% were male, and 82% were Caucasian. Most cases (93.8%) were elective, but urgent use of EVAR increased from 4% in the first 5 years to 7.3% in the last 5 years of the study period. Mean aneurysm size was 5.8 cm. Patients were followed for an average of 3 years (range, 1-11 years); 8% were lost to follow-up. Intraoperatively, 4.5% of patients required adjunctive maneuvers for endoleak, fixation, or flow-limiting issues. The 30-day mortality rate was 1.2%, and the perioperative morbidity rate was 6.6%. Intraoperative type I and II endoleaks were uncommon (2.3% and 9.3%, respectively). Life-table analysis at 5 years demonstrated excellent overall survival (66%) and freedom from ARM (97%). Postoperative endoleak was seen in 30% of patients and was associated with an increase in sac size over time. Finally, the total reintervention rate was 15%, including 91 instances (5%) of revisional EVAR. The overall major adverse event rate was 7.9% and decreased significantly from 12.3% in the first 5 years to 5.6% in the second 5 years of the study period (P < .001). Overall ARM was worse in patients with postoperative endoleak (4.1% vs 1.8%; P < .01) or in those who underwent reintervention (7.6% vs 1.6%; P < .001).

CONCLUSIONS

Results from a contemporary EVAR registry in an integrated health care system demonstrate favorable perioperative outcomes and excellent clinical efficacy. However, postoperative endoleak and the need for reintervention continue to be challenging problems for patients after EVAR.

Stent graft types for endovascular repair of abdominal aortic aneurysms

BACKGROUND

The UK prevalence of abdominal aortic aneurysm (AAA) is estimated at 4.9% in over 65-year olds. Progressive and unpredictable enlargement can lead to rupture. Endovascular repair of AAAs involves a stent graft system being introduced via the femoral artery and manipulated within the aorta under radiological guidance. Following endograft deployment, a seal is formed at the proximal and distal landing zones to exclude the aneurysm sac from the circulation. With the increasing popularity of endovascular repair there has been an increase in the number of commercially available stent graft designs on the market.

OBJECTIVES

This review aimed to assess the different stent graft types for endovascular repair of AAA.

SEARCH METHODS

The Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator (TSC) searched the Specialised Register (last searched November 2012) and CENTRAL (2012, Issue 10). Trial databases were searched by the TSC for details of ongoing and unpublished studies.

SELECTION CRITERIA

All published and unpublished randomised controlled trials (RCTs) of stent graft types in the repair of AAAs were sought without language restriction and in consultation with the Peripheral Vascular Disease Group TSC.

DATA COLLECTION AND ANALYSIS

We planned to conduct data collection and analysis in accordance with the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

No studies were identified that met the inclusion criteria.

AUTHORS' CONCLUSIONS

Unfortunately, no data exist regarding direct comparisons of the performance of different stent graft types. Therefore, this review cannot recommend guidance to clinicians in their selection of stent graft types. High quality randomised controlled trials evaluating stent graft types in abdominal endovascular aneurysm repair are required.

The role of mandatory lifelong annual surveillance after thoracic endovascular repair

Thoracic endovascular aortic repair (TEVAR) has become an attractive and well-accepted option for the management of the various thoracic aortic pathologies that vascular surgeons are confronted with. As in the abdominal aorta, current management trends include the treatment of younger patients with longer life expectancies, raising the issue of postoperative surveillance. There are several relevant differences between these anatomic areas when it comes to surveillance, including the relative inaccessibility of the thoracic aorta to ultrasound interrogation and the increased variability of thoracic aortic pathologies and post-TEVAR complications. In addition, concerns regarding radiation-induced carcinogenesis and contrast-induced nephropathy reduce the enthusiasm of many surgeons for regular computed tomography surveillance. Most agree that surveillance is important after TEVAR, but the method, duration, and frequency of that surveillance is much less clear and is the topic of this debate.

Role of pre-operative multiple gated acquisition scanning in predicting long-term outcome in patients undergoing elective abdominal aortic aneurysm repair

OBJECTIVE

To determine whether resting pre-operative left ventricular ejection fraction (LVEF) estimated by multiple gated acquisition scanning (MUGA) predicts long-term survival in patients undergoing elective abdominal aortic aneurysm (AAA) repair.

METHODS

A retrospective study of MUGA scans which were performed to estimate pre-operative resting LVEF in 127 patients [106 (83 %) males, mean age 74 ± 7.6 years] who underwent elective AAA repair over a period of 4 years from March 2007. We compared outcomes and long-term survival between patients who had a pre-operative LVEF ≤ 40 % (Group 1, n = 60) and LVEF > 40 % (Group 2, n = 67).

RESULTS

Overall 19 (15 %) patients died during the follow-up period (13 patients in group 1 and 6 patients in group 2). 30-day mortality was 8 %. There was no significant difference between group 1 and 2 in terms of patients' mean age or median length of hospital stay (8 days for both groups, p = 0.61). However, group 2 had more females than group 1(18 vs. 3, p = 0.001). Median survival for patients in group 2 was significantly higher than patients in group 1 (1,258 days vs. 1,000 days, p = 0.03). In a Cox regression model which included age, sex, smoking status and LVEF as covariates, only smoking status and LVEF predicted survival [Hazard ratio (HR) = 1.06, p = 0.04 and HR = 0.93, p = 0.00, respectively].

CONCLUSION

This study shows that there is a role for pre-operative MUGA scan assessment of resting LVEF in predicting long-term survival post elective AAA repair and that the lower the pre-operative LVEF the poorer the long-term outcome.

The impact of abdominal aortic aneurysm surgery on intensive care unit resources in an Irish tertiary centre

BACKGROUND

The potential impact of surgical service reconfiguration on intensive care unit (ICU) resources needs to be assessed.

AIMS

To determine the resources required to provide post-operative ICU care to patients undergoing open abdominal aortic aneurysm (AAA) repair or endovascular aneurysm repair (EVAR) at a specialist centre in the HSE South area

METHODS

For 198 patients, we calculated: (1) ICU bed-days; (2) organ support required; and (3) monetary cost of ICU care.

RESULTS

In total, 82.8% (101/122) of patients undergoing open AAA repair required post-operative ICU care (52 emergency and 49 elective). Emergency cases required more ICU bed-days (median 4.2 vs. 1.9, p<0.0005) and were more likely to require ventilation (odds ratio, OR 11.7, p<0.0001), inotropes (OR 3.1, p=0.01) or enteral nutrition (OR 23.3, p<0.0001). Mean cost per patient was €3,956 for elective cases and €16,419 for emergency cases. No patient required ICU admission after EVAR (n=76).

CONCLUSIONS

Open AAA surgery places significant demands on ICU resources. The planned reconfiguration of surgical services in Ireland must provide for parallel investment in ICU facilities and expertise.

Abdominal aortic aneurysm: an often asymptomatic and fatal men's health issue

Men are more likely than women to develop an abdominal aortic aneurysm (AAA), a disease that is often asymptomatic and has up to a 90% risk of mortality if the aneurysm ruptures. What many men do not know is that an AAA can easily be identified through an ultrasound screening, and if the aneurysm is >5.5 cm, it can be surgically repaired to prevent a life-threatening rupture. Although current AAA screening recommendations focus on men between the ages of 65 and 75 years, who have ever smoked, recent evidence suggest many men of ages 50 to 80 years, regardless of smoking status, may also be at risk for developing an AAA. This article presents a comprehensive overview of AAA disease and summarizes current evidence-based diagnostic and treatment guidelines, the importance of educating men about this health issue, and the need for more widespread AAA ultrasound screening opportunities.