M.R.H.M. van Sambeek

Early Results from the ENGAGE Registry: Real-world Performance of the Endurant Stent Graft for Endovascular AAA Repair in 1262 Patients

OBJECTIVE The ENGAGE registry was undertaken to examine the real-world outcome after endovascular abdominal aortic aneurysm (AAA) repair (EVAR) with the Endurant Stent Graft in a large, contemporary, global series of patients. METHODS From March 2009 to April 2011, 1262 AAA patients (89.6% men; mean age 73.1 years, range 43-93 years) were enrolled from 79 sites in 30 countries and treated with Endurant. Results are described following the reporting standards for EVAR. Follow-up data were tabulated for all 1262 patients at a 30-day follow-up and for the first 500 patients at a 1-year follow-up. RESULTS Intra-operative technical success was achieved in 99.0% of cases. Within 30 days, adverse events were reported in 3.9% of patients, including a 1.3% mortality rate. Type-I or -III endoleaks were identified in 1.5% of cases. Estimated overall survival, aneurysm-related survival and freedom from secondary interventions at 1 year were 91.6%, 98.6% and 95.1%, respectively. At 1 year, aneurysm size increased ≥ 5 mm in 2.8% and decreased ≥ 5 mm in 41.3% of cases. CONCLUSION Early results from this real world, global experience are promising and indicate that endovascular AAA repair with the Endurant Stent Graft is safe and effective across different geographies and standards of practice. Longer-term follow-up is necessary to assess durability of these results.

DISSECT: A New Mnemonic-based Approach to the Categorization of Aortic Dissection

OBJECTIVE/BACKGROUND Classification systems for aortic dissection provide important guides to clinical decision-making, but the relevance of traditional categorization schemes is being questioned in an era when endovascular techniques are assuming a growing role in the management of this frequently complex and catastrophic entity. In recognition of the expanding range of interventional therapies now used as alternatives to conventional treatment approaches, the Working Group on Aortic Diseases of the DEFINE Project developed a categorization system that features the specific anatomic and clinical manifestations of the disease process that are most relevant to contemporary decision-making. METHODS AND RESULTS The DISSECT classification system is a mnemonic-based approach to the evaluation of aortic dissection. It guides clinicians through an assessment of six critical characteristics that facilitate optimal communication of the most salient details that currently influence the selection of a therapeutic option, including those findings that are key when considering an endovascular procedure, but are not taken into account by the DeBakey or Stanford categorization schemes. The six features of aortic dissection include: duration of disease; intimal tear location; size of the dissected aorta; segmental extent of aortic involvement; clinical complications of the dissection, and thrombus within the aortic false lumen. CONCLUSION In current clinical practice, endovascular therapy is increasingly considered as an alternative to medical management or open surgical repair in select cases of type B aortic dissection. Currently, endovascular aortic repair is not used for patients with type A aortic dissection, but catheter-based techniques directed at peripheral branch vessel ischemia that may complicate type A dissection are considered valuable adjunctive interventions, when indicated. The use of a new system for categorization of aortic dissection, DISSECT, addresses the shortcomings of well-known established schemes devised more than 40 years ago, before the introduction of endovascular techniques. It will serve as a guide to support a critical analysis of contemporary therapeutic options and inform management decisions based on specific features of the disease process.

Systematic review and meta-analysis of sex differences in outcome after intervention for abdominal aortic aneurysm

The aim of this study was to assess possible differences in mortality between men and women with an abdominal aortic aneurysm (AAA) treated either by elective repair or following aneurysm rupture.

The Influence of Wall Stress on AAA Growth and Biomarkers

OBJECTIVES This study investigated the relation between abdominal aortic aneurysm (AAA) wall stress, AAA growth rate and biomarker concentrations. With increasing wall stress, more damage may be caused to the AAA wall, possibly leading to progression of the aneurysm and reflection in up- or downregulation of specific circulating biomarkers. Levels of matrix metalloproteinase-9, tissue inhibitor of matrix metalloproteinase-1, C-reactive protein and alpha 1-antitrypsin were therefore evaluated. METHODS Thirty-seven patients (maximum AAA diameter 41-55mm) with two, three or four consecutive computed tomography angiography (CTA) scans were prospectively included. Diameter growth rate in mm/year was determined between each pair of two sequential CTA scans. AAA wall stress was computed by finite element analysis, based on the first of the two sequential CTA scans only (n=69 pairs). Biomarker information was determined in 46 measurements in 18 patients. The relation between AAA diameter and wall stress was determined and the AAAs were divided into three equally sized groups (relative low, medium and high stress). Growth rate and biomarker concentrations were compared between these groups. Additionally, correlation coefficients were computed between absolute wall stress, AAA growth and biomarker concentrations. RESULTS A relative low AAA wall stress was associated with a lower aneurysm growth rate. Growth rate was also positively related to MMP-9 plasma concentration (r=0.32). The average MMP-9 and CRP concentrations increased with increasing degrees of relative wall stress, although the absolute and relative wall stress did not correlate with any of the biomarkers. CONCLUSION Although lower relative wall stress was associated to a lower AAA growth rate, no relation was found between biomarker concentrations and wall stress. Future research may focus on more and extensive biomarker measurements in relation to AAA wall stress.

Epidemiology, Aetiology, Risk of Rupture and Treatment of Abdominal Aortic Aneurysms: Does Sex Matter?

OBJECTIVES To unravel the extent to which gender plays a role in the epidemiology, aetiology, risk of rupture and treatment of abdominal aortic aneurysms (AAAs) and to give an overview of these factors. DESIGN, MATERIALS AND METHODS A literature review was performed in the Medline database and Cochrane Library for gender-specific articles on epidemiology, aetiology, risk of rupture and treatment of AAAs. RESULTS Our literature review suggests that the prevalence of AAA in women is underestimated. Regarding aetiology, an oestrogen-mediated reduction in macrophage MMP-9 production seems to be an important mechanism causing gender-related differences in AAA development. We found consensus in the literature that women run a greater risk of rupture compared to men under the current management rules for AAAs. Their treatment mortality also seems to be higher for both elective and ruptured repair. CONCLUSIONS Gender-specific guidelines should be put into place for the management of AAAs and awareness for this disease should be increased, both in women themselves and in their doctors.

Carotid stenting versus carotid endarterectomy: evidence basis and cost implications.

OBJECTIVE Carotid Angioplasty combined with Stenting (CAS) is increasingly performed because of its presumed benefits. A study was performed to identify key factors that determine the cost-effectiveness as compared to conventional carotid endarterectomy (CEA). METHODS The incremental cost-effectiveness of CAS over CEA for different scenarios was estimated using a modeling approach. Treatment costs were based on actual costs of successful procedures whereas costs of complications were taken from the literature. Patient survival was modeled using the endarterectomy patients from the ECST trial. RESULTS Procedural costs of CAS are higher than those of CEA, mainly as a result of the high material costs. Cost-effectiveness of CAS primarily depends on major stroke rates. One percent increase in the peri-operative major stroke rate causes a cost increase of 1051 euros and a loss of 0.06 quality adjusted life years. CONCLUSIONS At present CAS is at best non-inferior to CEA in terms of clinical outcome. Cost savings due to shorter admission are offset by the high costs associated with catheter-based interventions. At present CAS should be restricted to controlled settings until clinical trials have shown a substantial clinical benefit.

Editor's Choice - Use of Disposable Radiation-absorbing Surgical Drapes Results in Significant Dose Reduction During EVAR Procedures

OBJECTIVES Because of the increasing number of interventional endovascular procedures with fluoroscopy and the corresponding high annual dose for interventionalists, additional dose-protecting measures are desirable. The purpose of this study was to evaluate the effect of disposable radiation-absorbing surgical drapes in reducing scatter radiation exposure for interventionalists and supporting staff during an endovascular aneurysm repair (EVAR) procedure. MATERIALS This was a randomized control trial in which 36 EVAR procedures were randomized between execution with and without disposable radiation-absorbing surgical drapes (Radpad: Worldwide Innovations & Technologies, Inc., Kansas City, US, type 5511A). Dosimetric measurements were performed on the interventionalist (hand and chest) and theatre nurse (chest) with and without the use of the drapes to obtain the dose reduction and effect on the annual dose caused by the drapes. RESULTS Use of disposable radiation-absorbing surgical drapes resulted in dose reductions of 49%, 55%, and 48%, respectively, measured on the hand and chest of the interventionalist and the chest of the theatre nurse. CONCLUSIONS The use of disposable radiation-absorbing surgical drapes significantly reduces scatter radiation exposure for both the interventionalist and the supporting staff during EVAR procedures.

EVAR Suitability is not a Predictor for Early and Midterm Mortality after Open Ruptured AAA repair

OBJECTIVE The reported mortality reduction of emergency endovascular aneurysm repair (eEVAR) compared with open repair in patients with a ruptured abdominal aortic aneurysm (rAAA), as observed in observational studies, might be flawed by selection bias based on anatomical suitability for eEVAR. In the present study, we compared mortality in EVAR suitable versus non-EVAR-suitable patients with a ruptured AAA who were all treated with conventional open repair. MATERIALS AND METHODS In all patients presenting with a suspected rAAA, computed tomography angiography (CTA) scanning was performed. All consecutive patients with a confirmed rAAA on preoperative CTA scan and treated with open repair between April 2002 and April 2008 were included. Anatomical suitability for eEVAR was determined by two blinded independent reviewers. Outcomes evaluated were mortality (intra-operative, 30-day, and 6-month), morbidity, complications requiring re-intervention and length of hospital stay. RESULTS A total of 107 consecutive patients presented with a rAAA and underwent preoperative CTA scanning. In 25 patients, eEVAR was performed. In the 82 patients who underwent open repair, CTA showed an EVAR-suitable rAAA in 33 patients (41.8%) and a non-EVAR-suitable rAAA in 49 patients. Thirty-day and 6-month mortality rate was 15/33 (45.5%; 95% confidence interval (CI) 28.1-63.7) and 18/33 (54.5%; 95% CI 36.4-71.9) in the EVAR-suitable group versus 24/49 (49.0%; 95% CI 34.4-63.7) (P=0.75) and 29/49 (59.2%; 95% CI 44.2-73.0) (P=0.68) in the non-EVAR-suitable group, respectively. CONCLUSIONS The present study suggests that anatomical suitability for EVAR is not associated with lower early and midterm mortality in patients treated with open ruptured AAA repair. Therefore, the reported reduction in mortality between eEVAR and open repair is unlikely due to selection bias based on anatomical AAA configuration.

Challenging the Evidence for Pre-emptive Coil Embolisation of the Internal Iliac Artery during Endovascular Aneurysm Repair

OBJECTIVES We retrospectively analysed the results of a strategy in which coverage of the internal iliac artery (IIA) during endovascular aneurysm repair (EVAR) was routinely performed without coil embolisation. METHODS From January 2010 until May 2012, 32 patients (96.9% men; mean age 73.0 years, range 52-89 years) underwent EVAR with stent grafts extended into the external iliac artery (EIA), all without prior coil embolisation. Aneurysm morphology was determined on preoperative computed tomography (CT) images. During follow-up, patients were interviewed about buttock claudication, and the occurrence of endoleaks and evolution of aneurysm diameter were recorded. RESULTS At baseline, the mid-common iliac artery (CIA) diameter was 33.5 ± 16.8 mm and seven patients presented with ruptured aneurysms. Mean follow-up was 14.3 ± 7.4 months. There were eight deaths, none related to IIA coverage. Buttock claudication occurred in seven (22.6%) patients, which persisted after 6 months in two cases of bilateral IIA coverage. No Type-I or -II endoleaks occurred related to IIA coverage. Aneurysm growth was not observed. CONCLUSION Endovascular treatment of aortoiliac and iliac aneurysm without pre-emptive coil embolisation of the IIA appears safe and effective. No IIA-related endoleaks or re-interventions occurred in our series. This approach saves operating time, contrast load and costs and may reduce complications. However, a larger population and longer follow-up is required to confirm our findings.

Treatment of Post-implantation Aneurysm Growth by Laparoscopic Sac Fenestration: Long-term Results

OBJECTIVES Sac growth after endovascular aneurysm repair (EVAR) is an important finding, which may influence prognosis. In case of a type II endoleak or endotension, clipping of side branches and subsequent sac fenestration has been presented as a therapeutic alternative. The long-term clinical efficacy of this procedure is unknown. METHODS The study included eight patients who underwent laparoscopic aortic collateral clipping and sac fenestration for enlarging aneurysms following EVAR. Secondary interventions and clinical outcome were retrieved from hospital records. Sac behaviour was evaluated measuring volumes on periodical computed tomography angiography (CTA) imaging using dedicated software. RESULTS Follow-up had a median length of 6.6 (range 0.6-8.6) years. During this time, only three patients successfully achieved durable aneurysm shrinkage (n = 2) or stability (n = 1). The remaining patients suffered persistent (n = 2) or recurrent sac growth (n = 3), all regarded as failure of fenestration. A total of six additional interventions were performed, comprising open conversion (n = 2), relining (n = 1) and implantation of iliac extensions (n = 3). All additional interventions were successful at arresting further sac growth during the remainder of follow-up. CONCLUSIONS Despite being a less invasive alternative to conversion and open repair, the long-term outcome of sac fenestration is unpredictable and additional major procedures were often necessary to arrest sac growth.