The Gore Excluder US multi-center trial: analysis of adverse events at 2 years

Using the Evaluating Devices Using Claims and RegisTry Data (EDUCATe) Plan within the Vascular Implant Surveillance and Interventional Outcomes Network (VISION) to Analyze the Long-Term Outcomes following Endovascular Aortic Aneurysm Repair

BACKGROUND

Implanted devices undergo clinical trials to assess their safety and effectiveness. However, pivotal device trials are limited in their follow-up while postmarket surveillance may incompletely capture late failure. Linking clinical trials to Medicare claims can address these limitations. This study matched patients from investigational device exemption (IDE) clinical trials for endovascular aortic aneurysm repair (EVAR) to Medicare claims-based registry data to compare long-term device outcomes between the 2 sources.

METHODS

Patient-level data from 2 industry-sponsored IDE trials of EVAR devices was provided by a single industry partner. Trial data were matched at the patient level to data from the Vascular Implant Surveillance and Interventional Outcomes Network (VISION), a registry that is a part of the Society for Vascular Surgery Patient Safety Organization. The primary outcomes analyzed were survival and freedom from aneurysm-related reintervention.

RESULTS

Of 159 clinical trial patients, 134 were eligible for claims-based matching and 115 (85.5%) were successfully matched to VISION registry data. For the matched cohort, the Kaplan-Meier estimated survival was 94.8% at 1 year, 82.6% at 3 years, and 68.1% at 5 years. Estimates for freedom from reintervention were 90% at 1 year, 82.4% at 3 years, and 78.1% at 5 years. The estimates for survival were nearly identical between the clinical trial data and that found in the VISION data (log-rank P = 0.89). Freedom from reintervention was similar between the groups, with IDE trial reported freedom from reintervention of 87.3% and 73.3%, compared to VISION of 92.6% and 83% at 1 and 5 years, respectively (log-rank P = 0.13).

CONCLUSIONS

Clinical trial patients who undergo EVAR can be successfully matched to claims-based registry data to improve long-term device surveillance and outcomes reporting. Claims-based results agreed well with IDE trial results for patients through 5 years, supporting the accuracy of claims-based data for longer-term surveillance. Linking clinical trial and claims-based registry data can lead to robust device monitoring.

A Systematic Review of the Recruitment and Outcome Reporting by Sex and Race/Ethnicity in Stent Device Development Trials for Endovascular Abdominal Aortic Aneurysm Repair

BACKGROUND

Women and racial/ethnic minority groups have been shown to experience poor outcomes after endovascular aortic aneurysm repair (EVAR). One potential reason is the rare inclusion of these populations in initial phases of device development. The objective of this systematic review is to understand enrollment and outcome reporting by sex and race/ethnicity in industry-funded EVAR device development trials.

METHODS

MEDLINE, PubMed, and Embase were searched from inception to January 2022 without language restrictions using the following terminology: "stent", "graft", "endograft", "device", and "abdominal aortic aneurysm" (AAA).

CLINICALTRIALS

gov was also searched from inception to January 2022 for "AAA." Two independent reviewers screened and extracted data. All phase I-III and postmarket evaluation trials that included patients ≥18 years of age, who underwent EVAR were assessed. Participation-to-prevalence ratios (PPRs) were calculated to estimate representation of participants by sex and race/ethnicity in trials compared with their share of disease burden.

RESULTS

Among the 4,780 retrieved articles, 55 industry-funded trials met inclusion criteria for this review. A total of 51 trials (93%) reported enrollment by sex/gender, and only 7 trials (13%) reported enrollment by race/ethnicity of the participants. A median of 19 (interquartile range [IQR]: 4.5, 51) women participants were recruited compared to 171 (IQR: 57, 311.5) men, and 17 (IQR: 7.5, 21.5) racial/minority patients were recruited compared to 241 (IQR: 123, 463.5) White participants. Women represent 16.6% of the disease population, and the median PPR is 0.62 (IQR: 0.42, 0.88), which has remained constant over time (Figure 1). None of the device trials reported outcomes based on sex/gender or race/ethnicity.

CONCLUSIONS

This systematic review highlights the disparities in recruitment and outcome reporting based on sex and race/ethnicity in EVAR device development trials. While most trials may be underpowered to study these differences, recent registry studies show differential outcomes based on sex and race/ethnicity of vascular patients. Therefore, it is imperative to include and report outcomes in these participants, starting from the initial device development phases to improve generalizability of device-use and understand sources of variation in device performance.

Long-term outcome results after endovascular aortoiliac aneurysm repair with the bifurcated EXCLUDER Endoprosthesis

OBJECTIVE

To report the long-term outcome of patients presenting with an aortic, aortoiliac, or isolated common iliac aneurysm treated with the bifurcated EXCLUDER Endoprosthesis. Furthermore, potential differences in late outcome results between the original- and low-permeability endoprosthesis were analyzed.

METHODS

A retrospective analysis of prospectively collected data of 182 patients who underwent endovascular aneurysm repair with the EXCLUDER Endoprosthesis between June 1998 and October 2015 in an academic, tertiary care center for aortic disease was performed. Patient follow-up was from 3 to 20 years (mean follow-up of 6.9 years). Primary end points were overall survival and reintervention-free survival. Secondary end points were device-related complications, endoleaks, and reinterventions.

RESULTS

Overall survival at 5, 10, and 15 years was 72.8%, 42.1%, and 12.2%, respectively, with no aneurysm-related mortality and no difference in overall survival between the original- vs low-permeability endoprosthesis group (P = .617). Freedom from type I endoleak at 5 years was 94.8%. No new type I endoleak was detected beyond the 5-year follow-up mark. No type III endoleak was identified. Reintervention-free survival was 83.6%, 66.7%, and 66.7% at 5-, 10-, and 15-year follow-up, respectively. There was a significant difference in intervention-free survival between the original- vs low-permeability endoprosthesis group (P = .029) and after the 5-year follow-up mark. In addition, patients with the low-permeability endoprosthesis showed significantly fewer device-related complications (P = .002) and endoleaks (P = .005).

CONCLUSIONS

Endovascular aneurysm repair using the EXCLUDER Endoprosthesis is effective and durable on long-term follow-up, with acceptably low device-related complications and reinterventions. The low-permeability endoprosthesis was associated with significantly fewer new device-related complications and endoleaks after 5 years of follow-up.

Epidemiology of abdominal aortic aneurysms

Abdominal aortic aneurysm (AAA) disease remains a major source of morbidity in developed countries and can progress to life-threatening rupture if left untreated, with exceedingly high mortality. The goal of AAA management is to identify and electively repair AAAs before rupture. AAA disease burden and outcomes have improved over time with declining tobacco use and advancements in care across patients' disease course. The introduction of endovascular AAA repair, in particular, has allowed for elective AAA repair in patients previously considered too high risk for open surgery and has contributed to lower rates of AAA rupture over time. However, these improved outcomes are not universally experienced, and disparities continue to exist in the detection, treatment, and outcomes of AAA by sex, race, and ethnicity. Mitigating these disparities requires enhanced, focused efforts at preventing disease, promoting health, and delivering appropriate care among an increasingly diverse patient population.

Endovascular Aneurysm Sealing is Associated with Higher Medium-Term Survival than Traditional EVAR

BACKGROUND

Endovascular aneurysm repair (EVAR) is the dominant treatment modality for abdominal aortic aneurysm (AAA). Periprocedural risks are low, and cardiovascular events are the principle determinants of long-term survival. Recently, the concept of endovascular aneurysm sealing (EVAS) has been introduced into clinical investigation. In previous cohort studies, EVAS has been associated with a lower all-cause mortality than expected despite device issues. We used a propensity weighted approach to investigate whether EVAS was associated with lower all-cause mortality after aneurysm repair.

METHODS

We compared 333 patients in the Nellix United States Investigational Device Exemption trial to 15,431 controls from the Vascular Quality Initiative between 2014 and 2016 after applying the exclusion criteria from the investigational device exemption (hemodialysis, creatinine > 2.0 mg/dL, or rupture). We calculated propensity scores and applied inverse probability weighting to compare risk adjusted medium-term survival using Kaplan-Meier and Cox regression.

RESULTS

After weighting, patients treated with the Nellix EVAS system experienced higher 3-year survival than controls from the Vascular Quality Initiative (93% vs. 88%, respectively). This corresponded to a 41% lower risk of mortality for EVAS compared with EVAR (HR 0.59 [0.38-0.92], P = 0.02). Subgroup analysis demonstrated that the association between EVAS and higher survival was strongest in the subgroup of patients with aneurysms over 5.5 cm (P for interaction < 0.001). In this subgroup, EVAS patients experienced half the rate of mortality as those patients treated with EVAR, with 3-year survival of 92% compared with 86% (HR 0.5 [0.3-0.9], P = 0.02).

CONCLUSIONS

In this select group of patients, EVAS was associated with higher medium-term survival than traditional EVAR. Although issues with the device have recently surfaced, this exploratory analysis shows that the concept of sac sealing may hold promise. Further study is needed to confirm this finding and determine whether EVAS is associated with lower rates of cardiovascular events.

Fascia Suture Technique and Suture-mediated Closure Devices: Systematic Review

Background  The aim of the present study is to review the available data on suture-mediated closure devices (SMCDs) and fascia suture technique (FST), which are alternatives for minimizing the invasiveness of percutaneous endovascular aortic aneurysm repair (p-EVAR) and reduce the complications related to groin dissections. Methods  The Medline, ClinicalTrials.gov, and Cochrane library - Cochrane Central Register of Controlled Trials (CENTRAL) databases were searched for publications regarding SMCD and FST between January 1999 and December 2016. Results  We review 37 original articles, 30 referring to SMCDs (Prostar XL and Proglide), which included 3,992 patients, and 6 articles referring to FST, which include 426 patients. The two techniques are compared only in one article (100 patients). The two types of SMCDs were Prostar and Proglide. In most studies on SMCDs, the reported technical success rates were between 89 and 100%, but the complication rates varied greatly between 0 and 25%. Concerning FST, the technical success rates were also high, ranging between 87 and 99%. However, intraoperative complication rates ranged between 1.2 and 13%, whereas postoperative complication rates varied from 0.9 to 6.2% for the short-term and from 1.9 to 13.6% for the long-term. Conclusions  SMCDs and FST seem to be effective and simple methods for closing common femoral artery (CFA) punctures after p-EVAR. FST can reduce the access closure time and the procedural costs with a quite short learning curve, whereas it can work as a bailout procedure for failed SMCDs suture. The few failures of the SMCDs and FST that may occur due to bleeding or occlusion can easily be managed.

Comparison of Endovascular Stent Grafts for Abdominal Aortic Aneurysm Repair in Medicare Beneficiaries

BACKGROUND

Increased renal complications have been suggested with suprarenal stent grafts, but long-term analyses have been limited. Therefore, the purpose of this study was to evaluate the effect of endograft choice on perioperative and long-term outcomes.

METHODS

We compared Medicare beneficiaries undergoing endovascular abdominal aortic aneurysms repair from 2005 to 2008 with endografts with infrarenal fixation and a single docking limb (AneuRx, Excluder) to those with suprarenal fixation and 2 docking limbs (Zenith), or a unibody configuration (Powerlink). Propensity score weighting accounted for differences in patient characteristics among the different graft formations, and perioperative mortality, complications, and length of stay and 4-year rates of survival, rupture, and reintervention were compared.

RESULTS

Forty-six thousand one hundred seventy-one Medicare beneficiaries were identified including 11,002 (24%) with suprarenal fixation, 32,909 (71%) with infrarenal fixation, and 2,260 (5%) with a unibody graft. After propensity score weighting, there were no significant differences in patients' baseline clinical and demographic characteristics. The suprarenal fixation patients had higher rates of perioperative mortality (1.7% vs. 1.3%, P < 0.01), renal failure (6.0% vs. 4.7%, P < 0.001), and mesenteric ischemia (0.7% vs. 0.4%, P < 0.01) and longer length of stay (3.4 days vs. 3.0 days, P < 0.001) compared with patients with infrarenal fixation. Unibody grafts had higher rates of renal failure (5.9% vs. 4.7%, P < 0.001), mesenteric ischemia (1.0% vs. 0.4%, P < 0.001), and conversion to open repair (0.7% vs. 0.1%, P < 0.001) compared to those with infrarenal fixation and single docking limbs. At 4 years, mortality remained slightly higher with suprarenal compared to infrarenal fixation (30% vs. 29%, P = 0.047), although these patients had fewer conversions to open repair (0.6% vs. 0.9%, P = 0.03) and aneurysm-related reinterventions (10% vs. 12%, P < 0.01). At 4 years, unibody grafts had more aneurysm-related interventions compared to infrarenal fixation grafts (15% vs. 12%, P < 0.01) but fewer conversions to open repair (0.4% vs. 0.9%, P = 0.02). Late rupture did not differ among the groups.

CONCLUSIONS

Compared to infrarenal fixation devices, patients who underwent EVAR with suprarenal fixation had higher perioperative mortality and renal complications but fewer reinterventions including conversion, while the unibody graft had more perioperative complications and aneurysm-related reinterventions, but fewer conversions to open repair. Although these differences could be explained by selection bias, these data suggest that further comparative effectiveness analyses should be performed to understand the outcomes following EVAR with suprarenal fixation and unibody grafts.

Midterm outcome of EndoAnchors for the prevention of endoleak and stent-graft migration in patients with challenging proximal aortic neck anatomy

PURPOSE

To explore the use of EndoAnchors as an adjunct to endovascular abdominal aortic aneurysm repair for prevention of proximal neck complications in patients with challenging neck anatomy.

METHODS

Over a 28-month period, 208 patients (159 men; mean age 72±8 years) were enrolled in the ANCHOR prospective, multicenter registry (ClinicalTrials.gov; identifier NCT01534819) for prophylaxis against proximal neck complications. Patients were eligible when, in the opinion of the investigators, they were at increased risk for type Ia endoleak or migration owing to a hostile neck (length <10 mm, diameter >28 mm, angulation >60°, mural thrombus or calcium >2 mm in thickness or >180° in circumference, or conical shape). Overall, 123/157 (78.3%) patients met the criteria for a hostile neck according to core laboratory assessment of 157 adequate preoperative computed tomographic (CT) images.

RESULTS

Implantation of EndoAnchors was technically successful in 204/208 (98.1%) patients. The frequency of fracture was 0.3% (3/1118); there were no clinical sequelae associated with the fractures. Over the mean 14-month follow-up, 95.2% of patients were alive, and no deaths were attributable to EndoAnchors. There were no ruptures, migrations, or open surgical conversions. Aneurysm-related reinterventions were performed in 8 (3.8%) patients. Among 130 patients with postprocedure contrast CT studies, core laboratory analysis identified 2 (1.5%) patients with type Ia endoleaks. Aneurysm sac diameter decreased >5 mm in 42.9% of patients with CT scans at or beyond 1 year; 1.6% of patients developed sac enlargement >5 mm.

CONCLUSION

Prophylactic EndoAnchor use for challenging aortic neck anatomy was associated with satisfactory midterm results.

Successful endovascular management of an aortic rupture following stent placement for severe atherosclerotic stenosis: A case report

Aortic rupture during endovascular procedures is a devastating complication that mandates expedient intervention. The present report describes a case in which endovascular treatment was used to successfully manage an aortic rupture following placement of a covered stent graft for severe infrarenal aortic stenosis. Successful management of this case was the result of the procedure being performed in an operating room under appropriate anesthesia and close hemodynamic monitoring. Bilateral common femoral arterial access and use of covered aortic stent grafts also contributed to a favourable outcome.

Endovascular treatment of peripheral vascular disease

Peripheral arterial disease (PAD) affects about 27 million people in North America and Europe, accounting for up to 413,000 hospitalizations per year with 88,000 hospitalizations involving the lower extremities and 28,000 involving embolectomy or thrombectomy of lower limb arteries. Many patients are asymptomatic and, among symptomatic patients, atypical symptoms are more common than classic claudication. Peripheral arterial disease also correlates strongly with risk of major cardiovascular events, and patients with PAD have a high prevalence of coexistent coronary and cerebrovascular disease. Because the prevalence of PAD increases progressively with age, PAD is a growing clinical problem due to the increasingly aged population in the United States and other developed countries. Until recently, vascular surgical procedures were the only alternative to medical therapy in such patients. Today, endovascular practice, percutaneous transluminal angioplasty with or without stenting, is used far more frequently for all types of lower extremity occlusive lesions, reflecting the continuing advances in imaging techniques, angioplasty equipment, and endovascular expertise. The role of endovascular intervention in the treatment of limb-threatening ischemia is also expanding, and its promise of limb salvage and symptom relief with reduced morbidity and mortality makes percutaneous transluminal angioplasty/stenting an attractive alternative to surgery and, as most endovascular interventions are performed on an outpatient basis, hospital costs are cut considerably. In this monograph we discuss current endovascular intervention for treatment of occlusive PAD, aneurysmal arterial disease, and venous occlusive disease.

Effects of study design and trends for EVAR versus OSR

Purpose:

To investigate if study design factors such as randomization, multi-center versus single center evidence, institutional surgical volume, and patient selection affect the outcomes for endovascular repair (EVAR) versus open surgical repair (OSR). Finally, we investigate trends over time in EVAR versus OSR outcomes.

Methods:

Search strategies for comparative studies were performed individually for: OVID’s MEDLINE, EMBASE, CINAHL, HAPI, and Evidence Based Medicine (EBM) Reviews (including Cochrane DSR, ACP Journal Club, DARE and CCTR), limited to 1990 and November 2006.

Results:

Identified literature: 84 comparative studies pertaining to 57,645 patients. These include 4 randomized controlled trials (RCTs), plus 2 RCTs with long-term follow-up. The other 78 comparative studies were nonrandomized with 75 reporting perioperative outcomes, of which 16 were multi-center, and 59 single-center studies. Of the single-center studies 31 were low-volume and 28 were high-volume centers. In addition, 5 studies had all patients anatomically eligible for EVAR, and 8 studies included high-risk patients only. Finally, 25 long term observational studies reported outcomes up to 3 years.

Outcomes:

Lower perioperative mortality and rates of complications for EVAR versus OSR varied across study designs and patient populations. EVAR adverse outcomes have decreased in recent times.

Conclusion:

EVAR highlights the problem of performing meta-analysis when the experience evolves over time.

Review of Interventional Repair for Abdominal Aortic Aneurysm

Abdominal aortic aneurysm is associated with high mortality rate. For over 50 years, open surgical repair was the standard approach for large aneurysms. However, over the past decade, endovascular aneurysm repair (EVAR) has emerged as a viable alternative. EVAR is associated with lower operative and short-term morbidity and mortality and similar long-term survival (up to 4 years) compared with surgical repair. Endoleak remains a significant limitation associated with aneurysm expansion and reintervention. With newer, more versatile endograft designs, improvements in durability, and better surveillance techniques, the utilization of EVAR is likely to continue to expand.

The Endowedge and Kilt Techniques to Achieve Additional Juxtarenal Seal during Deployment of the Gore Excluder Endoprosthesis

The proximal 4 mm of the Gore Excluder endoprosthesis are scalloped. Our purpose is to describe our initial experience of a novel technique, referred to as the "endowedge," that takes advantage of this scalloped configuration in aneurysms with short proximal necks. The technique utilizes a balloon in the renal artery to aid alignment of a scallop and allow additional juxtarenal seal. A retrospective review of aneurysms treated with the endowedge technique at our institution was initiated. Renal balloons were placed via the brachial approach. Excluder endografts were deployed by flowering the first one or two rings, then advancing upward against the inflated balloon during completion of deployment. In patients with dumbbell-shaped morphology, an aortic cuff was deployed in the distal seal zone prior to the main body (kilt technique). Eight patients were identified, three of whom underwent an adjuvant kilt procedure. Average preoperative proximal neck length was 8.5 mm (range 6-12). Average additional juxtarenal seal was 2.3 mm. Mean follow-up was 5 months (range 2.5 weeks to 9 months). There were no type I endoleaks. There were two type II endoleaks. Average aneurysm size decreased from 6.0 to 5.5 cm. No aneurysm has enlarged or ruptured. We conclude that the endowedge technique allows additional juxtarenal seal during endograft placement. Our early results suggest that this technique may allow for safe treatment of aneurysms with short necks.

The development of endotension is associated with increased transmission of pressure and serous components in porous expanded polytetrafluoroethylene stent-grafts: Characterization using a canine model

OBJECTIVE

This study used a canine model of abdominal aortic aneurysms (AAAs) to compare intra-aneurysmal pressure and thrombus formation after exclusion with Dacron and expanded polytetrafluoroethylene (ePTFE) stent-grafts.

METHODS

Prosthetic AAAs with implanted strain-gauge pressure transducers were treated by stent-graft exclusion using Food and Drug Administration-approved devices in 10 mongrel dogs: five Dacron (AneuRx) and five ePTFE (original Excluder). Intra-aneurysmal pressure was measured over 4 weeks after AAA exclusion and indexed to the systemic pressure, represented as a percentage of a simultaneously obtained systemic pressure (value = 1.0). Magnetic resonance imaging (MRI) of the intra-aneurysmal thrombus was performed at 1, 2, and 4 weeks after exclusion and expressed as a signal-to-noise ratio (S:N) to control for background signal intensity. Comparisons of pressures and S:N between the two stent-grafts was analyzed with the Student's t test. Intra-aneurysmal thrombus was characterized histologically.

RESULTS

In animals excluded with both Dacron and ePTFE stent-grafts, the intra-aneurysmal pressure was nonpulsatile and reduced to <30% of systemic pressure. Significantly greater pressure transmission was observed after AAA exclusion using ePTFE compared with Dacron stent grafts (systolic pressure: ePTFE, 0.28 +/- 0.12 vs Dacron, 0.11 +/- 0.02, P < .001; mean pressure: ePTFE, 0.16 +/- 0.08 vs Dacron, 0.06 +/- 0.02, P < .001). MRI confirmed the absence of perfusion in all aneurysms. The T1-weighted signal intensity remained persistently elevated (S:N at 1 week, 2.7 +/- 0.4 vs 2 weeks, 4.0 +/- 0.2 vs 4 weeks, 5.4 +/- 1.3) in ePTFE-treated intra-aneurysmal thrombus, suggesting an absence of thrombus organization. In contrast, progressive evolution of T1 signal intensity in aneurysms excluded by Dacron stent-grafts was consistent with maturation from intact red blood cells (S:N at 1 week, 3.3 +/- 0.4) to methemoglobin (S:N at 2 weeks, 6.1 +/- 0.8), and then hemosiderin and ferritin (S:N at 4 weeks, 2.4 +/- 0.5). Histologically, ePTFE-excluded aneurysms contained poorly organized thrombus with red blood cell fragments and haphazardly arranged fibrin deposition indicative of active remodeling and continued influx of transudated serum. In aneurysms excluded by Dacron stent-grafts, dense, mature collagenous connective tissue and organized fibrin were present, indicative of greater thrombus organization.

CONCLUSIONS

Stent-graft treatment reduces intra-aneurysmal pressure to <30% of systemic pressure when no endoleak is present; however, significantly greater pressure is present in aneurysms treated with porous ePTFE stent-grafts than Dacron grafts. Histologic and MRI imaging analysis suggest that active transudation of serous blood components may be contributing to this increased intra-aneurysmal pressure.

Fenestrated and Branched Endografts: Assessment of Proximal Aortic Neck Fixation

PURPOSE

To investigate proximal fixation characteristics of different aortic endograft designs: a suprarenally placed fenestrated endograft, a modular branched endograft, an infrarenal endograft with suprarenal bare stent fixation, and the gold standard, a conventional hand-sewn anastomosis.

METHODS

Ten human cadaveric aortas were obtained at autopsy and transected 20 mm below the renal arteries to mimic an infrarenal aneurysm neck. In random order, the infrarenal, fenestrated, and branched endografts were deployed into the aorta. Using a hydraulic material testing machine, longitudinal load was applied to the distal end of each endograft until migration occurred, thus defining the displacement force (DF). Subsequently, a hand-sewn infrarenal anastomosis was tested in a similar manner.

RESULTS

The median DF was 4.67 N (3.82-6.37) for the infrarenal endograft, 9.17 N (8.03- 10.81) for the fenestrated endograft, and 16.95 N (14.78-19.67) for the branched endograft. The differences in DF between the infrarenal and fenestrated endografts and between the fenestrated and branched designs were statistically significant (both p=0.005). The median force to dislodge the graft from the conventional anastomosis was 89.16 N (71.24-105.23).

CONCLUSIONS

Suprarenally placed endografts, especially with additional branch grafts, provide improved proximal fixation compared to an infrarenal endograft with suprarenal bare stent fixation. However, none of the tested endografts approached the optimal, time-proven fixation, the hand-sewn anastomosis.

Abdominal Aortic Aneurysm:. A Review of Endoluminal Treatment

Abdominal aortic aneurysm (AAA) carries a high mortality if left untreated. Until recently, most patients with AAA were treated with surgical repair. However, endoluminal graft treatment is rapidly becoming an alternative to surgical repair due to lower morbidity and comparable perioperative mortality rates. Despite this optimism patients and operators should keep in mind the palliative nature of these endovascular repairs and the lifelong need for surveillance, before embarking on these procedures. Endoleaks remain to be a significant problem leading to aneurysm expansion and occasionally rupture. Durability of the existing endograft devices remains to be seen. Careful patient selection is critical to success with these procedures. With future advancements in the endograft device technology, methods of patient surveillance, and patient care, there may be a shift from conventional surgical approaches to endovascular repair for the treatment of AAA.

Overview of success of EVAR: Progress to date

Endovascular aneurysm repair (EVAR) of abdominal aortic aneurysms has been challenged by a number of groups, and the shortcomings of this procedure have been documented in the scientific literature. However, patients and physicians continue to pursue this procedure as a viable means of treating abdominal aortic aneurysms. Both device evolution and advancement of technical skills have led to dramatic improvements in the outcomes of EVAR within the last decade. These improvements and accomplishments have also been chronicled in the literature. This review looks at the successes of EVAR, based on both US Food and Drug Administration trials and independent studies comparing conventional open repair and endovascular repair.

Late problems at the proximal aortic neck: Migration and dilation

Migration is a late-term complication of endovascular aneurysm repair (EVAR) evidenced by downward slippage of the endograft. The etiology of migration may be inherent to problems with endograft fixation, although aortic neck dilation may also play a role. Devices with active fixation (ie, hooks and barbs) possess an additional mechanism of fixation and may better resist migration. Aortic neck dilation after EVAR is significant in a subset of patients and may be related to neck degeneration. Excessive oversizing of endografts may contribute to dilation and migration and is, therefore, not recommended. Migration should be treated when the overlap between the endograft and aortic neck is less than 10 mm or when associated with clinically significant events such as type I endoleak or aneurysm expansion. Failure to treat migration could lead to repressurization and subsequent rupture of the aneurysm.

Endovascular Repair of Abdominal Aortic Aneurysms Using 3 Commercially Available Devices:Midterm Results

PURPOSE

To report the early and midterm results of 3 commercially available stent-grafts for abdominal aortic aneurysm (AAA) exclusion.

METHODS

Since fall 1999, 151 patients (137 men; mean age 74 years, range 54-88) have undergone AAA repair using 88 Ancure, 46 AneuRx, and 17 Excluder stent-grafts in elective procedures. All patients were followed clinically and underwent postoperative duplex ultrasound and/or computed tomographic angiography, which was repeated every 6 months.

RESULTS

The mean overall follow-up was 17 months (range 1-46). Initial technical failure was 3% (3/88) for Ancure versus 0% for AneuRx and Excluder. Primary endoleak occurred in 8% (7/88) of the Ancure patients versus 22% (10/46) for AneuRx and 6% (1/17) for Excluder (p=NS). Early (30-day) graft thrombosis (2/151, 1%) was seen only in the Ancure group. The perioperative complication rates (excluding endoleak and fever) were 22% (19/ 88) for Ancure, 15% (7/46) for AneuRx, and 0% for Excluder (p=NS). There was only 1 (0.7%) perioperative death in the series (Ancure patient). More ancillary procedures were performed in the Ancure group (p<0.05). Postoperatively, the size of the AAA decreased or remained unchanged in 76% for Ancure patients versus 75% for AneuRx and 64% for Excluder (p=NS). The incidences of late endoleak were 6% for Ancure, 2% for AneuRx, and 0% for Excluder (p=NS). The freedom from late endoleak at 3 years was 88% for Ancure and 97% for AneuRx (100% at 1 year for Excluder). Survival rates were similar. No AAA rupture was recorded.

CONCLUSIONS

The Ancure device has slightly higher overall perioperative complications and early technical failure than AneuRx or Excluder. All 3 devices are effective in preventing aneurysm rupture; the overall midterm survival rates, freedom of endoleak, and limb patency are somewhat similar.