Aneurysm Diameter and Proximal Aortic Neck Diameter Influence Clinical Outcome of Endovascular Abdominal Aortic Repair: A 4-Year EUROSTAR Experience

ERA OF ENDOVASCULAR AORTIC ANEURYSM REPAIR IS LINKED TO PREOPERATIVE ANATOMIC SEVERITY AND PERIOPERATIVE PATIENT OUTCOMES

OBJECTIVE

Varying opinions on optimal elective and emergent surgical management of infrarenal AAAs are expressed by the most recent Society for Vascular Surgery (SVS), European Society for Vascular Surgery (ESVS), versus NICE (National Institutes for Health and Care Excellence, UK) guidelines. The NICE guidelines propose that open surgical repair (OSR) serve as the default treatment for infrarenal AAA. The rationale for this approach relied on data from the early era of endovascular aneurysm repair (EVAR), and are in contrast to the more balanced approaches of the SVS and ESVS. We hypothesize that significant differences in patient selection, management, and postoperative outcome are related to the era in which treatment was undertaken, contextualizing the outcomes reported in early era EVAR RCTs.

METHODS

Retrospectively, two cohorts representing all EVAR patients from "early", n= 167 (2008-2010) and "late" n=129 (2015-2017) periods at a single treating institution, were assembled. Primary outcomes of era-related changes in preoperative demographics, anatomy, and intraoperative events were assessed; anatomy was compared using the Society for Vascular Surgery Anatomic Severity Grading (ASG) system. These era-related differences were then placed in the context of early perioperative outcomes and at follow-up to one year.

RESULTS

Choice of surgical strategy differed by era, despite the same patient preoperative comorbidities between EVAR groups. Preoperative anatomic severity was significantly worse in the early cohort (p<.001), with adverse proximal and distal seal zone features (p<·001). Technical success was 16·2% higher in the late cohort, with significantly fewer type 1A/B endoleaks perioperatively (p<.001). In-hospital complications, driven by higher acute kidney injury and surgical site complications in the early cohort, resulted in a 16·5% difference between cohorts (p<0·05). At one year of follow-up, outcome differences persisted; late era patients had fewer 1A endoleaks, fewer graft complications, and better reintervention-free survival.

CONCLUSIONS

From a granular dataset of EVAR patients, we found an impact of EVAR repair era on early clinical outcome; late cohort infrarenal (IR) EVAR patients had less severe preoperative anatomy, and improved perioperative and follow-up outcomes to one year, suggesting that the results of early EVAR RCTs may no longer be generalizable to modern practice.

The Effect of Abdominal Aortic Aneurysm Size on Endoleak, Secondary Intervention and Overall Survival Following Endovascular Aortic Aneurysm Repair

OBJECTIVE

The purpose of this study was to identify the effect of abdominal aortic aneurysm (AAA) size on endoleak development and secondary intervention after endovascular repair (EVAR), as well as to examine the effect on overall survival and cause of mortality.

METHODS

Retrospective analysis was performed on all non-ruptured AAA treated by elective EVAR using FDA-approved endografts in our facility from July 2004 to December 2017. Patients were grouped into 3 cohorts based on preoperative aneurysm size: Group I (<5.5 cm), Group II (5.5-6.4 cm), and Group III (≥ 6.5 cm). Occurrences of endoleak, secondary intervention and overall survival underwent univariate and multivariate analysis. Cause of death data on deceased patients was similarly examined.

RESULTS

A total of 517 patients were analyzed. There was no difference between size groups in the rate of endoleak (Group I 48/277, 17.3%; Group II 33/160, 20.6%; Group III 18/80, 22.5%; p = 0.46) or time until endoleak development. Univariate analysis showed no difference in the rate of secondary intervention (Group I 36/277, 13.0%; Group II 24/160, 15.0%; Group III 18/80, 22.5%; p = 0.11), time until intervention or number of interventions performed. Multivariate analysis showed an association with shorter time to secondary intervention for both Group III aneurysms (HR 2.03, 95% CI 1.11-3.73; p = 0.02) and female patients (HR 1.79, 95% CI 1.02-3.13; p = 0.04). There was no difference in overall survival, aneurysm-related mortality or overall cause of mortality.

CONCLUSION

AAA diameter prior to EVAR was not associated with any differences in rates of endoleak or secondary intervention, and was not associated with poorer overall survival or greater aneurysm-related mortality. Patients with suitable anatomy for EVAR can be considered for this intervention without concern for increased complications or poorer outcomes related to large aneurysm diameter alone.

Endoluminal Management of Infra-renal Aortic and Aorto-iliac Aneurysms

This paper reviews the development of endovascular aneurysm repair (EVAR) of infra-renal aortic and iliac artery aneurysms and considers the current status and best treatment options. The vast majority of devices are bifurcated and exclude the aneurysm utilizing the same techniques for fixation and seal. The modern EVAR procedure is usually performed in a hybrid operating theatre, utilizing image fusion and other radiation-reducing techniques and using optimized procedural techniques, including percutaneous access. The best outcomes are achieved in patients whose anatomy is within device "instructions for use", but these are most commonly breached due to "hostile" neck anatomy. Endovascular options for these cases include the use of fenestrated endografts, chimney grafts and endoanchors. Concomitant iliac artery aneurysms often occur with abdominal aortic aneurysms, and endovascular options include limb extensions with internal iliac embolization as well as iliac branch devices. The durability of EVAR has recently been called into question by long-term results from early EVAR randomized trial. Findings such as infra-renal neck dilatation and aneurysm sac expansion are relatively common and associated with adverse outcomes. This durability concern mandates regular and long-term imaging and clinical surveillance. It also indicates that EVAR technology is not fully evolved with a need for further development to improve patient applicability and long-term durability.

Multicentre randomised controlled trial to evaluate the efficacy of pre-emptive inferior mesenteric artery embolisation during endovascular aortic aneurysm repair on aneurysm sac change: protocol of Clarify IMA study

INTRODUCTION

Type II endoleak (EL) is frequently seen after endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA) and is often considered responsible for aneurysm sac enlargement if it persists. In order to reduce type II EL and consequent sac enlargement, pre-emptive embolisation of the inferior mesenteric artery (IMA), which is a main source for persistent type II EL, has been introduced in many vascular centres. At present, there is a lack of robust evidence to support the efficacy of pre-emptive embolisation of IMA on reduction of persistent type II EL with subsequent sac shrinkage.

METHOD AND ANALYSIS

This multicentre, randomised controlled trial will recruit 200 patients who have fusiform AAA ≥50 mm/rapidly enlarging fusiform AAA, with patent IMA, and randomly allocate them either to a pre-emptive IMA embolisation group or non-embolisation control group in a ratio of 1:1. The primary endpoint is the difference of aneurysm sac volume change assessed by CT scans between the pre-emptive IMA embolisation group and the control group at 12 months after EVAR. The secondary endpoints are defined as change of aneurysm sac volume in both groups at 6 and 24 months, freedom from sac enlargement at 12 and 24 months after EVAR, prevalence of type II EL at 1, 6, 12 and 24 months evaluated by contrast-enhanced CT, reintervention rate, aneurysm related mortality, overall survival, perioperative morbidity, volume of contrast media used during EVAR and dosage of radiation.

ETHICS AND DISSEMINATION

The protocol has been reviewed and approved by the ethics committee of Nara Medical University (No. 2113). The findings of this study will be communicated to healthcare professionals, participants and the public through peer-reviewed publications, scientific conferences and the University Hospital Medical Information Network Clinical Trials Registry home page.

TRIAL REGISTRATION NUMBER

UMIN000035502.

Prognostic significance of large diameter proximal aortic neck in endovascular aneurysm repair

Background: Adverse morphological features of the proximal aortic neck have been identified as culprits for late failure after endovascular aneurysm repair (EVAR). Our objective was to investigate the prognostic role of wide proximal aortic neck in EVAR. Methods: We conducted a review of the literature in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to identify studies comparing outcomes of EVAR in patients with large versus small proximal aortic neck. A meta-analysis of time-to-event data was performed with the inverse-variance method and the results were reported as summary hazard ratio (HR) and 95 % CI. We applied random-effects models of meta-analysis. Results: We identified 9 observational studies reporting on a total of 7,682 patients (1,961 with large diameter and 5,721 with small diameter neck). The hazard of death (HR 1.57, 95 % CI 1.23-2.01; P = 0.0003), aneurysm-related reintervention (HR 2.06, 95 % CI 1.23-3.45; P = 0.006), type Ia endoleak (HR 6.69, 95 % CI 4.39-10.20; P < 0.001), sac expansion (HR 10.07, 95 % CI 1.80-56.53; P = 0.009), aneurysm rupture (HR 2.96, 95 % CI 2.00-4.38; P < 0.0001), and neck-related adverse events (HR 10.33, 95 % CI 4.95-21.56; P < 0.0001) was higher in patients with large diameter proximal aortic neck than in those with small neck. Conclusions: Patients with a large proximal aortic neck were found to have poorer outcomes than those with small neck. This finding has implications in decision making when selecting methods for aneurysm treatment and in EVAR surveillance for aneurysm-related complications in this cohort of patients.

Anatomic predictors for late mortality after standard endovascular aneurysm repair

OBJECTIVE

Abdominal aortic aneurysm (AAA) management involves a decision process that takes into account anatomic characteristics, surgical risks, patients' preferences, and expected survival. Whereas larger AAA diameter has been associated with increased mortality after both standard endovascular aneurysm repair (EVAR) and open repair, it is unclear whether survival after EVAR is influenced by other anatomic characteristics. The purpose of this study was to determine the importance of baseline anatomic features on survival after EVAR.

METHODS

All patients treated at a tertiary teaching center with EVAR for intact standard infrarenal AAA from 2000 to 2014 were included. The civil data registry was queried to determine survival status; causes of death were obtained from death certificates. The primary study end point was to determine the impact of baseline morphologic features on all-cause and cardiovascular mortality after EVAR.

RESULTS

This study included 404 EVAR patients (12.1% women; mean age, 73 years) with a median follow-up of 5.8 years (interquartile range, 3.1-7.4 years). The 5- and 10-year overall survival rates for the entire population after EVAR were 70% (95% confidence interval [CI], 66%-75%) and 43% (95% CI, 37%-50%), respectively. Only AAA diameter >70 mm (hazard ratio [HR], 1.75; 95% CI, 1.20-3.56) was identified as an independent anatomic predictor of all-cause mortality. Death due to cardiovascular causes occurred in 60 (38.5%) patients. Aneurysm-related mortality was responsible for six of the cardiovascular-related deaths. In multivariable analysis, both neck diameter ≥30 mm (HR, 2.16; 95% CI, 1.05-4.43) and AAA diameter >70 mm (HR, 2.45; 95% CI, 1.34-4.46) were identified as independent morphologic risk factors for cardiovascular mortality, whereas >25% circumferential neck thrombus (HR, 0.32; 95% CI, 0.13-0.77) was protective.

CONCLUSIONS

This study suggests that patients with AAA diameters >70 mm are at increased risk of all-cause and cardiovascular mortality. In addition, patients with infrarenal neck diameters ≥30 mm have a greater risk of cardiovascular mortality, although AAA-related deaths were not more frequent in this group of patients. Consequently, a more aggressive management of cardiovascular medical comorbidities may be warranted to improve survival after standard EVAR in these patients.

Survival and Reintervention Risk by Patient Age and Preoperative Abdominal Aortic Aneurysm Diameter after Endovascular Aneurysm Repair

BACKGROUND

Endovascular aneurysm repair (EVAR) has become the standard of care for abdominal aortic aneurysm (AAA), but questions remain regarding the benefit in high-risk and elderly patients. The purpose of this study was to examine the effect of age, preoperative AAA diameter, and their interaction on survival and reintervention rates after EVAR.

METHODS

Our integrated health system's AAA endograft registry was used to identify patients who underwent elective EVAR between 2010 and 2014. Of interest was the effect of patient age at the time of surgery (≤80 vs. >80 years old), preoperative AAA diameter (≤5.5 cm vs. >5.5 cm), and their interaction. Primary endpoints were all-cause mortality and reintervention. Between-within mixed-effects Cox models with propensity score weights were fit.

RESULTS

Of 1,967 patients undergoing EVAR, unadjusted rates for survival at 4 years after EVAR was 76.1%, and reintervention-free rate was 86.0%. For mortality, there was insufficient evidence for an interaction between age and AAA size (P = 0.309). Patient age >80 years was associated with 2.53-fold higher mortality risk (hazard ratios [HR] = 2.53; 95% confidence intervals [CI], 1.73-3.70; P < 0.001), whereas AAA > 5.5 cm was associated with 1.75-fold higher mortality risk (HR = 1.75; 95% CI, 1.26-2.45; P = 0.001). For reintervention risk, there were no significant interactions or main effects for age or AAA diameter.

CONCLUSIONS

Age and AAA diameter are independent predictors of reduced survival after EVAR, but the effect is not amplified when both are present. Age >80 years or AAA size >5.5 cm did not increase the risk of reintervention. No specific AAA size, patient age, or combination thereof was identified that would contraindicate AAA repair.

Collected Transatlantic Experience From the PERICLES Registry: Use of Chimney Grafts to Treat Post-EVAR Type Ia Endoleaks Shows Good Midterm Results

Purpose: The aim of this retrospective analysis was to evaluate the performance of the chimney (ch) technique in the treatment of type Ia endoleaks after standard endovascular aneurysm repair (EVAR). Methods: Between January 2008 and December 2014, 517 chEVAR procedures were performed in 13 US and European vascular centers (PERICLES registry). Thirty-nine patients (mean age 76.9±7.1 years; 33 men) were treated for persistent type Ia endoleak and had computed tomography angiography or magnetic resonance angiography follow-up at >1 month. Endurant abdominal stent-grafts were used in the 20 cases. Single chimney graft placement was performed in 18 (46%) patients and multiple in 21 (54%). Overall, 70 visceral vessels were targeted for revascularization. Results: Technical success was achieved in 35 (89.7%) cases; 3 persistent type Ia endoleaks and 1 chimney graft occlusion were detected within the first 30 days. Thirty-day mortality was 2.6%. Two other deaths (not aneurysm related) occurred during a mean follow-up of 21.9 months (0.23–71.3). Primary patency of the chimney grafts was 94.3% at 36 months. In a subgroup analysis comparing Endurant to other stent-grafts, no significant differences were observed regarding persistent endoleak [1/20 (5%) vs 2/19 (11%), p=0.6] or reintervention [1/20 (5%) vs 0/19 (0%)]. Conclusion: The present series demonstrates that chEVAR in the treatment of post-EVAR type Ia endoleaks has satisfactory results independent of the abdominal and chimney graft combinations. Midterm results show that chEVAR is an effective method for treating type Ia endoleaks.

Outcomes of using endovascular aneurysm repair with active fixation in complex aneurysm morphology

OBJECTIVE

The ideal treatment option for patients with complex aneurysm morphology remains highly debated. The aim of this study was to investigate the impact of endovascular aneurysm repair (EVAR) with active fixation on outcomes in patients with complex aneurysm morphology.

METHODS

There were 340 consecutive patients who underwent EVAR using active fixation devices, 234 with active infrarenal fixation (AIF; Gore Excluder; W. L. Gore & Associates, Flagstaff, Ariz) and 106 with active suprarenal fixation (ASF; 85 Medtronic Endurant [Medtronic, Santa Rosa, Calif] and 21 Cook Zenith [Cook Medical, Bloomington, Ind]). Demographics, comorbidities, anatomic features, and outcomes were analyzed for patients receiving devices with active fixation. Outcomes of using active fixation in necks with <15-mm neck lengths, >60-degree infrarenal neck angle (β), >30-mm infrarenal neck diameter, severe aortic neck calcification or thrombus, and nonstraight neck morphology were evaluated.

RESULTS

Of the 340 patients, 106 (78 men; mean age, 74.5 ± 9.3 years at the time of surgery) received implants with ASF and 234 (191 men; mean age, 74.6 ± 8.9 years at the time of surgery) received implants with AIF. In comparing AIF and ASF devices, patients in the suprarenal fixation group had significantly shorter follow-up time (25 ± 17 months vs 44.3 ± 32 months; P < .0001). Patients in the ASF group had shorter aortic neck lengths (25.5 ± 15.1 mm vs 28.6 ± 14.9 mm; P = NS) and significantly larger infrarenal neck diameters (25.9 ± 6.3 mm vs 23.4 ± 3.2 mm; P < .0001) and aneurysm diameters (59.9 ± 11.6 mm v. 55.9 ± 10.0 mm; P = .002). Outcomes were similar between groups, with no significant differences in reintervention, proximal endoleak, sac growth, abdominal aortic aneurysm-related death, or rupture. Of the complex anatomic neck features investigated, neck diameter >30 mm and nonstraight neck morphology had the highest rates of reintervention in ASF devices.

CONCLUSIONS

In cases of hostile infrarenal neck morphology, ASF appears to be used more frequently. Our data suggest that ASF may be useful for certain patients but may be unfavorable for others, such as those with wide necks or several difficult neck features. Nevertheless, further research is needed to evaluate more optimal treatment options, such as fenestrated EVAR, branched EVAR, and endovascular adjuncts such as EndoAnchors (Aptus Endosystems, Sunnyvale, Calif), in dealing with high-risk anatomic characteristics that may not be optimally managed with standard EVAR devices with active fixation.

Challenging Anatomy Predicts Mortality and Complications After Endovascular Treatment of Ruptured Abdominal Aortic Aneurysm

Purpose: To analyze the effects of aortic anatomy and endovascular aneurysm repair (EVAR) inside and outside the instructions for use (IFU) on outcomes in patients treated for ruptured abdominal aortic aneurysms (rAAA). Methods: All 112 patients (mean age 73 years; 102 men) treated with standard EVAR for rAAA between 2000 and 2012 in 3 European centers were included in the retrospective analysis. Patients were grouped based on aortic anatomy and whether EVAR was performed inside or outside the IFU. Data on complications, secondary interventions, and mortality were extracted from the patient records. Cox regression analysis was performed to assess predictors of mortality and complications; results are presented as the hazard ratio (HR) with 95% confidence interval (CI). Survival was analyzed using the Kaplan-Meier method. Results: Of the 112 patients examined, 61 (54%) were treated inside the IFU, 43 (38%) outside the IFU, and 8 patients lacked adequate preoperative computed tomography scans for determination. Median follow-up of those surviving 30 days was 2.5 years. Mortality at 30 days was 15% (95% CI 6% to 24%) inside the IFU vs 30% (95% CI 16% to 45%) outside (p=0.087). Three-year mortality estimates were 33.8% (95% CI 20.0% to 47.5%) inside the IFU vs 56% (95% CI 39.7% to 72.2%) outside (p=0.016). At 5 years, mortality was 48% (95% CI 30% to 66%) inside the IFU vs 74% (95% CI 54% to 93%) outside (p=0.015). Graft-related complications occurred in 6% (95% CI 0% to 13%) inside the IFU and 30% (95% CI 14% to 42%) outside (p=0.015). The rate of graft-related secondary interventions was 14% (95% CI 4% to 22%) inside the IFU vs 35% (95% CI 14% to 42%) outside (p=0.072). In the multivariate analysis, neck length <15 mm (HR 8.1, 95% CI 3.0 to 21.9, p<0.001) and angulation >60° (HR 3.1, 95% CI 1.0 to 9.3, p=0.045) were independent predictors of late graft-related complications. Aneurysm neck diameter >29 mm (HR 2.5, 95% CI 1.1 to 5.9, p=0.035) was an independent predictor of overall mortality. Conclusion: Long-term mortality and complications after rEVAR are associated with aneurysm anatomy. The role of adjunct endovascular techniques and the outcome of open repair in cases with challenging anatomy warrant further study.

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.

Sealing zones have a greater influence than iliac anatomy on the occurrence of limb occlusion following endovascular aortic aneurysm repair

Limb occlusion is a well-known complication following endovascular aortic aneurysm repair (EVAR), and it very often leads to reoperation. The aim of this study is to identify predictive factors for limb occlusion following EVAR. Two hundred and twenty-four patients undergoing EVAR between 2004 and 2012 were included in this retrospective study. Demographics, anatomic, and follow-up data were compared between two groups (with or without thrombosis). Preoperative anatomy was analyzed with a dedicated workstation, using the Society of Vascular Surgery reporting standards. Eleven (4.9%) patients presented with a limb occlusion during follow-up (46 ± 12 months). Univariate analyses were first performed to investigate the influence of preoperative variables on limb occlusion. Then, variables with a p value <0.1 were included in the multivariate analysis and showed that in the occlusion group there was a greater rate of chronic renal failure (18.2% vs. 3.8%, p = 0.012), a more frequent occurrence of distal landing zones in the external iliac artery (15.4% vs. 2.1%, p = 0.006), and a smaller aortic neck diameter (21.0 ± 2.9 mm vs. 23.6 ± 3.3 mm, p = 0.014). Although iliac anatomy does not appear to have a significant influence on limb occlusion rate in the multivariate analysis, proximal and distal sealing zones appear to be involved in this complication.

Endovascular repair with chimney technique of abdominal aortic aneurysm with hostile aortic neck

Abdominal aortic aneurysm (AAA) with hostile aortic neck is not a good candidate for conventional endovascular aneurysm repair (EVAR), and a recent paper showed that EVAR with chimney technique (Ch-EVAR) yielded reasonable outcome. We report here a case of successful Ch-EVAR treatment of AAA with hostile neck. An 81-year-old man presented with a 71-mm AAA during evaluation of a gastric ulcer. Aortic neck was 30 mm in diameter, 10-15 mm in length and angulated by 100°. EVAR was performed with chimney stenting to both renal arteries, and the patient recovered after transient hematuria. At one-year follow-up, AAA had increased by 7 mm with delayed type I endoleak control without renal insufficiency. The patient needed close follow-up.

Aortic rupture and sac expansion after endovascular repair of abdominal aortic aneurysm

Background

Long-term concerns about the durability of endovascular aortic aneurysm repair (EVAR) remain after the publication of controlled trials. Increased expertise in endograft technology, case selection and postoperative reintervention has created a need for reappraisal of the longer-term efficacy of EVAR using contemporary data.

Methods

Patients undergoing infrarenal EVAR between 2004 and 2010 were studied prospectively. Morphological compliance with manufacturers' instructions for use (IFU) was established using three-dimensional computed tomography. The primary outcome measures were all-cause and aneurysm-related mortality, postoperative rupture, reintervention and sac expansion. These adverse events were reported using Kaplan–Meier survival analysis, with comparison within, or outside IFU by the log rank test.

Results

Some 478 patients of median age 76 years had a median aneurysm diameter of 62·9 mm. Median follow-up was 44 (range 11–94) months; 198 (41·4 per cent) were compliant with IFU. The 30-day mortality rate was 2·1 per cent (10 of 478 patients): nine (2·0 per cent) of 455 patients who had elective and one (4 per cent) of 23 patients who had non-elective surgery. Aneurysm-related mortality was 0·897 deaths per 100 person-years, and all-cause mortality was 8·558 deaths per 100 person-years, with significantly lower survival outside IFU (P = 0·012). Two patients had a late rupture (0·138 per 100 person-years), of whom one died. There were 6·120 reinterventions per 100 person-years, with no difference for aneurysms treated outside IFU (P = 0·136). Primary sac expansion occurred in 6·721 per 100 person-years and secondary sac expansion in 4·142 per 100 person-years.

Conclusion

In this series EVAR had a lower aneurysm-related mortality rate than demonstrated in early controlled trials, and with lower sac expansion rates than reported from image repositories. Data from earlier studies should be applied to current practice with caution.

Composite stent-grafts are not associated with increased endoleak or reintervention rates after endovascular abdominal aneurysm repair

BACKGROUND

Although present-generation endografts have expanded the indications for endovascular abdominal aneurysm repair, arterial anatomy frequently dictates the use of a combination of commercially available endografts and components for successful aneurysm repair. This study sought to determine whether there was an increase in endoleak or secondary intervention rates in individuals treated with composite endografts compared with noncomposite, or standard, endografts.

METHODS

From 1999 to 2009, 421 endovascular abdominal aneurysm repairs were performed at a single institution. A total of 384 patients met criteria for inclusion, with at least one follow-up imaging study. Patients were then identified as having had a composite endograft, defined as any combination of two or more different commercially available endograft or stent components, versus a standard endograft. Primary outcomes measured were freedom from endoleak and secondary intervention.

RESULTS

During the study period, 60 composite endograftings and 324 standard endograftings were performed. The groups were well matched for demographics, including age, gender, comorbidities, emergent need for procedure, and 30-day mortality (1.64% vs. 1.54%, nonsignificant). Median follow-up was 16.3 months (range, 19 days to 8.5 years) and 10.2 months (range, 4 days to 8.7 years) for composite and standard endografts, respectively. There was no significant difference between the groups in either endoleak or secondary intervention rates. Median time to endoleak detection was 2.0 months (range, 2 days to 3.9 years) for composite endografts and 2.8 months (range, 2 days to 6.9 years) for standard endografts. Median time to secondary intervention was 7.0 months (range, 4 days to 6.9 years) for composite endografts and 6.7 months (range, 1 day to 6.7 years) for standard endografts.

CONCLUSIONS

Composite endografts, namely, the combination of different commercially available endografts or stents used for the treatment of aortic aneurysms, are not associated with increased mortality, endoleak, or secondary intervention rates compared with noncomposite endografts.

Long-term outcomes of endovascular aneurysm repair for challenging aortic necks using the Talent endograft

The aim of the present paper is to evaluate the long-term outcomes of endovascular aneurysm repair (EVAR) for challenging aortic necks. Subgroup analyses were performed on 156 patients from the prospective multicenter Talent eLPS (enhanced Low Profile Stent Graft System) trial. Patients with high-risk aortic necks (length < 15 mm or diameter ≥28 mm) were compared with the remaining patients. Patients with high-risk (n = 86) and low-risk necks (n = 70) had similar age and gender distribution. Despite similar prevalences of co-morbidities, the high-risk group had higher Society for Vascular Surgery scores. The high-risk group also had larger maximum aneurysm diameters (56.6 versus 53.0 mm, P < 0.02). There were lower freedoms from major adverse events (MAEs) for the high-risk group at 30 days (84.9 versus 95.7%; P < 0.04) and 365 days (73.4 versus 89.2%; P = 0.02). Effectiveness endpoints at 12 m showed no significant differences. Freedom from all-cause mortality at 30 days (96.5 versus 100%) and aneurysm-related mortality at 365 days (96.0 versus 100%) were similar. At five years, there were no differences in endoleaks or change in aneurysm diameter. All migrations occurred in the high-risk group. The five-year freedom from aneurysm-related mortality for the high- and low-risk groups was 93.2 and 100%, respectively. In conclusion, despite a higher rate of MAEs within the first year and higher migration rates at five years, EVAR in aneurysms with challenging aortic necks can be treated with acceptable long-term results.

Clinical outcomes for hostile versus favorable aortic neck anatomy in endovascular aortic aneurysm repair using modular devices

BACKGROUND

Endovascular aneurysm repair (EVAR) is not generally recommended for patients with hostile neck anatomy. This study analyzed the clinical implications of various clinical features of proximal aortic neck anatomy.

METHODS

Prospectively collected data from 258 EVAR patients using modular devices were analyzed. Patients were classified as having favorable neck anatomy (FNA) or hostile neck anatomy (HNA). HNA was defined as any or all of length of <10 mm, angle of >60°, diameter of >28 mm, ≥50% circumferential thrombus, ≥50% calcified neck, and reverse taper. Univariate, multivariate, and Kaplan-Meier analyses were used to compare early and late clinical outcomes.

RESULTS

FNA was present in 37% and HNA was present in 63%. Clinical and demographic characteristics were comparable. Technical success was 99%. Mean follow-up was 22 months (range, 1-78 months). Perioperative complication rates were 3% for FNA vs 16% for HNA (P = .0027). Perioperative deaths were 0% for FNA and 3% for HNA (P = .2997). Proximal type I early endoleaks (intraoperative) occurred in 9% of FNA vs 22% for HNA (P = .0202). Intraoperative proximal aortic cuffs were used to seal endoleaks in 9% of FNA vs 22% of HNA (P = .0093). At late follow-up, abdominal aortic aneurysm expansion was noted in 6% of FNA vs 7% of HNA (P = .8509). Rates of freedom from late type I endoleaks at 1, 2, 3, and 4 years were 97%, 97%, 97%, and 90% for FNA vs 89%, 89%, 89%, and 89% for HNA (P = .1224); rates for late interventions were 95%, 90%, 90%, and 90% for FNA vs 95%, 93%, 91%, and 85% for HNA (P = .6902). Graft patency at 1, 2, and 3 years was 99%, 99%, and 99% for FNA vs 97%, 92%, and 90% for HNA (P = .0925). The survival rates were 93%, 84%, 76%, and 76% for FNA vs 88%, 82%, 74%, and 66% for HNA (P = .2631). Reverse taper was a significant predictor for early type I endoleak (odds ratio [OR], 5.25, P < .0001), reverse taper (OR, 5.95; P < .0001) and neck length (OR, 4.15; P = .0146) were for aortic cuff use; circumferential thrombus (OR, 2.44; P = .0448), and neck angle (OR, 3.38; P = .009) were for perioperative complications.

CONCLUSIONS

Patients with HNA can be treated with EVAR, but with higher rates of early (intraoperative) type I endoleak and intervention. The midterm outcomes are similar to FNA.

Predictors of reintervention after endovascular repair of isolated iliac artery aneurysm

The objective of this study was to identify factors predicting the need for reintervention after endovascular repair of isolated iliac artery aneurysm (IIAA). We reviewed prospectively collected database records of all patients who underwent endovascular repair of IIAA between 1999 and 2008. Detailed assessment of the aneurysms was performed using computed tomography angiography (CTA). Follow-up protocol included CTA at 3 months. If this showed no complication, then annual duplex scan was arranged. Multivariate analysis and analysis of patient survival and freedom from reintervention were performed using Kaplan-Meier life tables. Forty IIAAs (median diameter 44 mm) in 38 patients were treated (all men; median age 75 years), and median follow-up was 27 months. Endovascular repair of IIAA was required in 14 of 40 aneurysms (35%). The rate of type I endoleak was significantly higher with proximal landing zone (PLZ) diameter >30 mm in the aorta or >24 mm in the common iliac artery or distal landing zone (DLZ) diameter >24 mm (P = 0.03, 0.03, and 0.0014, respectively). Reintervention rate (RR) increased significantly with increased diameter or decreased length of PLZ; increased DLZ diameter; and endovascular IIAA repair (P = 0.005, 0.005, 0.02, and 0.02 respectively); however, RR was not significantly affected by length of PLZ or DLZ. Freedom-from-reintervention was 97, 93, and 86% at 12, 24, and 108 months. There was no in-hospital or aneurysm-related mortality. Endovascular IIAA repair is a safe treatment option. Proper patient selection is essential to decrease the RR.

Five-year results for the Talent enhanced Low Profile System abdominal stent graft pivotal trial including early and long-term safety and efficacy

OBJECTIVES

The pivotal trial of the Talent enhanced Low Profile System (eLPS; Medtronic Vascular, Santa Rosa, Calif) stent graft evaluated short and long-term safety and efficacy of endovascular aneurysm repair (EVAR). These data and a confirmatory group assessing the performance of the CoilTrac delivery system supported the United States premarket approval application for the device.

METHODS

The pivotal trial was a prospective, nonrandomized study conducted at 13 sites from February 2002 to April 2003. The study group (n = 166) underwent EVAR using the Talent eLPS stent graft. The control group (n = 243) underwent open surgical AAA repair. Data for this group were obtained from the Society for Vascular Surgery Endovascular AAA Surgical Controls project. Outcomes were compared at 30 days and 12 months. Additional 5-year follow-up was obtained for the eLPS group. A single-center cohort of 137 patients was the confirmatory group for the assessment of the clinical performance of the CoilTrac delivery system, with analysis of outcomes <or=30 days from the procedure.

RESULTS

AAA anatomy with neck length as short as 3 mm and maximum neck diameter of 32 mm were included in the eLPS group. EVAR was superior to open repair for periprocedural outcomes, including mean procedure duration (167.3 vs 196.4 minutes, P < .001), blood transfusion (18.2% vs 56.8%, P < .001), median intensive care unit stay (19.3 vs 74.3 hours, P < .001), and mean hospital stay (3.6 vs 8.2 days, P < .001). Freedom from major adverse events was 89.2% for EVAR at 30 days vs 44.0% (P < .001) and 81.3% vs 42.4% at 1 year (P < .001). Freedom from all-cause mortality and aneurysm-related mortality (ARM) was 93.7% and 98.2% for EVAR vs 92.4% and 96.7% for the controls. Through 5 years for the EVAR group, rates of freedom from all-cause mortality, ARM, aneurysm rupture, and conversion to surgery were 69.8%, 96.5%, 98.2%, and 99.1%, respectively, with one conversion to surgery, 25 secondary reinterventions, and five site-reported instances of stent graft migration. The technical success rate for the CoilTrac confirmatory group was 100%, with no aneurysm rupture or conversion to open repair at 30 days. The 30-day all-cause mortality rate was 1.5% (2 of 137).

CONCLUSIONS

In a population with challenging anatomic characteristics, EVAR with the Talent eLPS and use of the CoilTrac delivery system compared favorably with open repair through 1 year. Sustained protection from ARM, with minimal reinterventions, was attained through 5 years.

Thoracic Endograft for Abdominal Aortic Aneurysms, an Unusual Application for Severe Neck Angulation: Case Report and Literature Review

Our goal was to achieve complete proximal sealing in severe aortic neck angulation (SNA) during endovascular aneurysm repair (EVAR) of a patient with an abdominal aortic aneurysm (AAA) unfit for surgery. An 82-year-old patient with an infrarenal AAA of 9.8 cm with an SNA of 90° was admitted for acute coronary syndrome. Following coronary treatment, the patient was considered unfit for surgery and therefore was evaluated for EVAR. Aneurysm sac exclusion was obtained with the deployment of a Powerlink bifurcated graft (Endologix Inc, Irvine, CA) inside a Relay thoracic endograft (Bolton Medical, Florida) placed just below the most distal renal artery. At 6 months, computed tomographic angiography confirmed correct graft placement, complete aneurysm exclusion, and a reduction in the aneurysmal sac. In AAA patients with an SNA at high risk of EVAR failure, the adaptability of a thoracic endograft could be considered for proximal sealing.

AAA stent-grafts: past problems and future prospects

Endovascular aneurysm repair (EVAR) has quickly gained popularity for infrarenal abdominal aortic aneurysm repair during the last two decades. The improvement of available EVAR devices is critical for the advancement of patient care in vascular surgery. Problems are still associated with the grafts, many of which can necessitate the conversion of the patient to open repair, or even result in rupture of the aneurysm. This review attempts to address these problems, by highlighting why they occur and what the failings of the currently available stent grafts are, respectively. In addition, the review gives critical appraisal as to the novel methods required for dealing with these problems and identifies the new generation of stent grafts that are being or need to be designed and constructed in order to overcome the issues that are associated with the existing first- and second-generation devices.

The proximal fixation strength of modern EVAR grafts in a short aneurysm neck. An in vitro study

OBJECTIVES

The study aims to measure the strength of the proximal fixation of endografts in short and long necks.

DESIGN

Three types of endografts were compared: Gore Excluder, Vascutek Anaconda and Medtronic Endurant.

MATERIALS AND METHODS

The proximal part of the stent grafts was inserted in bovine arteries and the graft was then attached to a tensile testing machine. The force to obtain dislodgement (DF) from the aorta was recorded for each graft at proximal seal lengths of 10 and 15 mm.

RESULTS

The median DF (interquartile range, IQR) for the Excluder, the Anaconda and the Endurant with a seal length of 15 mm was: 11.8 (10.5-12.0) N, 20.8 (18.0-30.1) N and 10.7 (10.4-11.3) N. With the shorter proximal seal of 10mm, DF was, respectively: 6.0 (4.5-6.6) N, 17.0 (11.2-36.6) N and 6.4 (6.1-12.0) N.

CONCLUSIONS

The proximal fixation of the Anaconda is superior to the Excluder and the Endurant at short necks of 10 and 15 mm in an experimental set-up. There is a statistically significant decrease of proximal fixation for the Excluder stent graft, when decreasing the length of the proximal neck from 15 to 10 mm.

Can Laboratory Tests Predict the Prognosis of Patients after Endovascular Aneurysm Repair? Current Status and Future Directions

The purpose of this study was to determine what laboratory values predict the prognosis of patients after endovascular aneurysm repair (EVAR). MEDLINE and Cochrane Library databases were searched. This resulted in 13 relevant articles. Data were pooled, and meta-analyses were performed. A meta-analysis including 5,655 patients showed that preoperative serum creatinine > 1.5 mg/dL was a significant risk indicator for increased 30-day mortality (relative risk 3.0, 95% confidence interval 2.3–4.1, p < .0001). Four other studies showed that other cutoff values of creatinine or glomerular filtration rate can predict mortality and complications following EVAR. One study suggested that reduced preoperative hemoglobin is a risk indicator for reduced long-term survival. Increased serum creatinine, reduced glomerular filtration rate, and reduced hemoglobin are significant and strong predictors of mortality and complications after EVAR. Current evidence remains limited, and further research is needed to determine conclusively additional laboratory values that may predict the outcome of patients following EVAR.

Secondary Endovascular and Conversion Procedures for Failed Endovascular Abdominal Aortic Aneurysm Repair: Can We Still Be Optimistic?

The purpose of this study was to evaluate the incidence, etiology, and outcome of secondary endovascular and “open” conversion procedures after failed endovascular abdominal aortic aneurysm repair (EVAR). From January 1997 until December 2005, 625 patients with an infrarenal abdominal aortic aneurysm were treated by elective EVAR, with 98.7% ( n = 617) primary EVAR success. The mean follow-up of the 617 patients was 46.7 ± 11.2 months. One hundred of these patients (16.2%) required secondary endovascular or peripheral procedures, and 39 (6.3%) patients underwent a secondary abdominal conversion. There were 5 acute conversions (0.8%) and 34 elective conversions (5.5%). The pre-EVAR anatomic suitability data, the main cause of the secondary procedure, and stent graft type were compared between patients with primary EVAR success, patients in need of a secondary endovascular or peripheral procedure, and patients with abdominal conversion. The overall main causes for reinterventions were proximal migration ( n = 60; 9.7%), progressive kinking of the stent graft ( n = 59; 9.6%), and late type III endoleak ( n = 12; 1.9%). Multivariate logistic regression analysis showed that factors significantly correlated with secondary procedures were the abdominal aortic aneurysm's maximum diameter, the proximal neck's width and length, and particularly the commercial withdrawal of the stent graft ( p < .001). The morbidity and mortality rates of secondary endovascular or peripheral interventions were 0%. The mortality rate of acute secondary conversions was 20% ( n = 1) and of elective secondary conversions was 8.8% ( n = 3). The morbidity rates for acute and elective conversions were 0% and 65%, respectively. The aneurysm-related mortality rate in our series was below 1%. Abdominal conversion surgery still carries a high mortality rate, but the overall EVAR-related mortality rate remains low. Early pitfall detection and proper reintervention are crucial to long-term EVAR success.