Five-year results of endovascular abdominal aortic aneurysm repair with the Ovation abdominal stent graft

Use of the GORE Conformable Excluder Device in Highly Angulated Aortic Neck Anatomy: Mid-term Outcomes

INTRODUCTION

Patients with complex aortic anatomy require meticulous surgical planning to optimize intraoperative and postoperative outcomes. The GORE Excluder Conformable Abdominal Aortic Aneurysm Endoprosthesis (CEXC Device, WL Gore and Associates, Flagstaff, AZ) allows for endovascular treatment of highly angulated and short proximal neck abdominal aortic aneurysms (AAA). Owing to its recent approval, short-term clinical outcomes of this device remain scarce.

REPORT

In this report, we present a case series of 3 patients who underwent endovascular aortic repair using the GORE Excluder Conformable device with highly angulated (>70°) aortic neck anatomy. Endografts were deployed in a radiology suite using standard 2D angiography in conjunction with a CYDAR Medical (Wilmington, Delaware) reconstructed 3D overlay. The patients' ages were 85, 67, and 85 years. The mean abdominal aortic aneurysm diameter in these cases was 6.9 cm. The mean proximal neck length was 2.1 cm, proximal mean neck angulation was 83°. The mean operative time, total fluoroscopy time, and contrast used were 208 minutes, 28.3°minutes, and 94.5 milliliters, respectively. No adjunctive procedures, such as proximal cuff or endo-anchors, were performed at the time of index procedure.

DISCUSSION

Type Ia endoleak was observed in 1 patient post-operatively but after treatment with an aortic cuff there was no evidence of enlarging aneurysm sac. The GORE Excluder Conformable Endoprosthesis expands access to endovascular management of AAAs. Our early experience with this device demonstrated excellent patient and clinical outcomes in a highly angulated neck anatomy.

Five-Year Results for Abdominal Aortic Aneurysm Repair with the GORE® EXCLUDER® Device: Insights from the Gore Global Registry for Endovascular Aortic Treatment (GREAT)

BACKGROUND

The early postoperative benefits of endovascular aneurysm repair (EVAR) have been well established but questions remain regarding its durability at mid-term and long-term time points. Long-term results in real-world use of EVAR outside of randomized trial data are limited. This study used the Global Registry for Endovascular Aortic Treatment registry to explore the 5-year outcomes with the GORE EXCLUDER device in real-world clinical circumstances.

METHODS

All patients within the Global Registry for Endovascular Aortic Treatment registry who underwent an infrarenal abdominal aortic aneurysm repair with the GORE EXCLUDER device were included in this study. Baseline characteristics and demographic information of the cohort were collected. End points included mortality (all-cause and aneurysm-related), serious endoleaks, aneurysm sac diameter, endograft integrity (fracture, compression, migration), post-EVAR aortic rupture, device-related reintervention, conversion to open repair, graft explantation, and major adverse cardiovascular events.

RESULTS

A total of 3,216 patients were included in this analysis. The cohort reflected a significantly comorbid population with 46% of patients reaching a Charlson Comorbidity Index score of ≥5. Follow-up at 5 years was 60% of eligible participants. The freedom from aortic-related mortality was at 98.8% and overall survival was 71.2%. Postoperative major adverse cardiovascular events occurred in 49 (1.5%) patients. Device-related intervention through 5 years was 7.2% and the overall serious endoleak rate was 6.8%. Less than 1% of patients required an open conversion/revision and aortic rupture following device placement occurred in 15 (0.5%) patients. Aneurysm sac regression was achieved in 58.1% of patients at 5 years, and stability/absence of growth was observed in 83.6% at 5 years.

CONCLUSIONS

This study supports the durability of the GORE EXCLUDER device through 5 years with negligible incidence of graft integrity compromise and low aortic/device-related reintervention rates. Furthermore, the efficacy of the device is highlighted with low aortic-related mortality and high sac regression/stability diameter through 5 years.

The Impact of Proximal Neck Anatomy on the 5-Year Outcomes Following Endovascular Aortic Aneurysm Repair With the Ovation Stent Graft

PURPOSE

Hostile proximal neck anatomy has historically been associated with worse outcomes for endovascular aortic aneurysm repair (EVAR) of abdominal aortic aneurysms (AAA). We investigated the impact of proximal neck anatomy on the outcomes following EVAR with the Ovation abdominal stent graft (Endologix, Irving, Calif).

METHODS

We used prospectively collected data from the Effectiveness of Custom Seal with Ovation: Review of the Evidence database, compromised of pooled data from 6 clinical trials and the European Post-Market Registry of patients undergoing elective infrarenal EVAR (2009-2017). We investigated the impact of short neck length (<10 mm), wide neck diameter (≥28 mm), reverse taper shape (>10%), and neck angulation (>45°) on the outcomes. The primary outcome was type IA endoleak. Secondary outcomes included any type I/III endoleak, sac expansion, aneurysm-related reinterventions, and all-cause and aneurysm-related mortality, and a combined endpoint of type IA endoleak, graft migration, AAA-related reintervention, conversion, and aneurysm rupture. We used Kaplan-Meier analysis and Cox proportional hazards models to estimate the 30 day and 5 year rates and assess univariate and risk-adjusted differences.

RESULTS

Of the 1020 patients, 60 patients had a short neck, 113 had a wide neck diameter, 279 were reverse taper shaped, and 99 had neck angulation >45°. Wide proximal neck was associated with higher 5 year type IA endoleak estimates compared with favorable neck anatomy (7.1% vs 4.3%; p=0.02). No association with 5 year type IA endoleak was found for short neck length (1.7% vs 4.3%; p=0.52), reverse taper shape (3.2% vs 4.3%; p=0.99), or neck angulation (6.1% vs 4.3%; p=0.13). A wide neck diameter compared with favorable anatomy was also associated with higher 5 year estimates of graft migration (3.8% vs 0.4%; p=0.03) and the combined neck-related adverse outcome endpoint (16% vs 9.5%; p=0.002). The estimates of aneurysm sac expansion, rupture, and overall and aneurysm-related mortality were similar between the hostile proximal neck anatomy cohorts and favorable anatomy.

CONCLUSION

Wide proximal neck is associated with higher 5 year type IA endoleak rates for patients treated with the Ovation stent graft. However, short neck length, reverse taper shape, and neck angulation are not associated with higher 5 year type IA endoleak rates.

CLINICAL IMPACT

Hostile proximal neck anatomy has historically been associated with worse outcomes for endovascular aortic aneurysm repair of abdominal aortic aneurysms. The Ovation stent graft platform uses a different proximal sealing method using a polymer inflatable ring, aiming to improve sealing between the graft and aortic wall. This study demonstrated that short, angulated, and reverse taper-shaped neck anatomy did not result in increased type IA endoleak estimates in patients treated with the Ovation stent graft platform. Potentially, the different sealing mechanisms played a role in mitigating the historically worse outcomes in patients with short, angulated, and reverse taper-shaped neck anatomy.

Low profile endografts for the endovascular treatment of abdominal aortic aneurysms

INTRODUCTION

Favorable midterm outcomes have been reported with the use of low-profile endografts (LPE), but long-term data is still needed. Furthermore, it is unclear if each of these LPE may have advantages over the other, which may, in turn, affect the outcomes. We systematically reviewed the literature about complications and reintervention rates of patients submitted to endovascular aneurysm repair (EVAR) of abdominal aortic aneurysm (AAA) using LPE.

MATHERIALS AND METHODS

A literature search was conducted including articles that reported 30-days and follow-up mortality, complications, and reintervention rates of patients treated with EVAR using Incraft (Cordis), Zenith LP/Alpha (Cook Medical Inc) and Ovation (Endologix) endografts.

RESULTS

36 papers were evaluated, reporting results of 582 patients treated with Zenith device, 1211 with Incraft and 3449 with Ovation. During follow up, similar survival and freedom from reintervention rates were reported among the various types of endograft both at 1 and 3 years. The incidence of limb stenosis/kinking was significantly higher in patients treated with Zenith LP/Alpha (2.1%, P = 0.008), while the Incraft device had a significantly lower proportion of type III endoleaks (P < 0.001).

CONCLUSIONS

Long-term survival and freedom from reintervention rates were comparable among the three LPEs. The Cook Zenith device had the highest rates of limb stenosis/kinking, while the Incraft device had the lowest occurrence of type III endoleak.

PROSPERO

Registration number: CRD42022315875.

Pre-Emptive Embolization of the Aneurysm Sac or Aortic Side Branches in Endovascular Aneurysm Repair: Meta-Analysis and Trial Sequential Analysis of Randomized Controlled Trials

BACKGROUND

To investigate outcomes of pre-emptive embolization of the aneurysm sac or aortic side branches in endovascular aneurysm repair (EVAR).

METHODS

The review was reported as per Preferred Reporting Items for Systematic reviews and Meta-Analyses 2020 with a preregistered protocol. Bibliographic sources (MEDLINE, Embase, and CENTRAL) were searched using subject headings and free text terms. Randomized controlled trials comparing EVAR with versus without embolization were included. Pooled estimates of dichotomous outcomes were calculated using odds ratio (OR) or risk difference (RD) and 95% confidence interval (CI) applying the Mantel-Haenszel method. Continuous outcomes were summarized using mean difference (MD) and 95% CI applying the inverse variance method. The certainty of evidence was appraised with the Grading of Recommendations Assessment, Development, and Evaluation framework. Version 2 of the Cochrane tool was used to assess the risk of bias. Trial sequential analysis assumed alpha = 5% and power = 80%.

RESULTS

Four randomized controlled trials were included. No significant difference was found in aneurysm-related mortality (RD 0.00, 95% CI -0.03 to 0.03), overall mortality (OR 1.85, 95% CI 0.42-8.13), aneurysm rupture (RD 0.00, 95% CI -0.03 to 0.03), type II endoleak-related reintervention (RD -0.07, 95% CI -0.21 to 0.06), procedure time (MD 20.12, 95% CI -11.54 to 51.77), or fluoroscopy time (MD 11.17, 95% CI -11.22 to 33.56). Patients with pre-emptive embolization had significantly lower odds of type II endoleak (OR 0.45, 95% CI 0.26-0.78) and sac expansion (OR 0.19, 95% CI 0.07-0.52). The risk of bias was high for all outcomes. The certainty of evidence was very low for all outcomes, except for type II endoleak, for which it was low. Trial sequential analysis showed an inconclusive result for overall mortality and type II endoleak-related reintervention but confirmed the advantage of embolization in reducing type II endoleak and sac expansion.

CONCLUSIONS

Limited, low certainty data suggest pre-emptive embolization confers no clinical benefits in EVAR.

One-year safety and effectiveness of the Alto abdominal stent graft in the ELEVATE IDE trial

OBJECTIVE

This study reports the results of a prospective, multicenter trial designed to evaluate the safety and effectiveness of the polymer based Endologix Alto Stent Graft System in treating abdominal aortic aneurysms (AAAs), with sealing 7 mm below the top of the fabric in aortic neck diameters from 16 to 30 mm.

METHODS

Seventy-five patients were treated with Alto devices between March 2017 and February 2018 in 16 centers in the United States for infrarenal AAAs (max diameter ≥5.0 cm in diameter or size increase by 0.5 cm in 6 months or diameter ≥1.5 times the adjacent normal aorta). Patients were followed for 30 days, 6 months, and 1 year by clinical evaluation and computed tomography and abdominal x-ray imaging. Treatment success was defined as technical success and freedom from AAA enlargement, migration, type I or III endoleak, AAA rupture or surgical conversion, stent graft stenosis, occlusion, kink, thromboembolic events, and stent fracture attributable to the device requiring secondary intervention through 12 months. Preoperative characteristics, perioperative variables, follow-up clinical evaluations, and radiographic examination results through the first 1 year were analyzed.

RESULTS

The mean patient age was 73 years, with 93% of patients being male. The 30-day major adverse event rate was 5.3%. At 1 year, the primary endpoint was met with a treatment success rate of 96.7%. Through 1-year post-treatment, all-cause mortality was 4.0%. No AAA-related mortality occurred. AAA enlargement was 1.6%, type I endoleak rate was 1.4%, with 100% freedom from type III endoleaks, device migration, device fracture, stent occlusion, or AAA rupture. The device-related secondary intervention rate was 2.7%.

CONCLUSIONS

This prospective study demonstrates the Endologix Alto is safe and effective in treating AAAs with appropriate anatomy at 1 year. The safety endpoint is met by a 5.3% 30-day major adverse event rate, whereas the effectiveness endpoint is met by a treatment success rate of 96%.

Endografts for the treatment of abdominal aortic aneurysms with a hostile neck anatomy: A systematic review

Background

Endovascular aortic repair (EVAR) of abdominal aortic aneurysms (AAAs) has emerged as a better alternative to conventional open surgery for AAAs. The purpose of the review is to define the improvement in the clinical management of the patient with hostile neck AAAs due to the introduction of new endografts while giving a thorough description of their instructions for use (IFUs), main characteristics and part sizing, reporting their outcomes from clinical studies and categorizing their usability.

Methods

A MEDLINE search was conducted using keyword-specific combinations. Clinical studies were searched via the clinicaltrials.gov website. Relevant articles' references were also hand-searched.

Results

We retrieved 640 records describing Alto, Ovation iX, Treovance, Aorfix, Anaconda, Conformable, and Endurant II/IIs endografts. Aortic necks >60° can be managed with Anaconda, Aorfix, and Conformable, which can treat up to 90° necks requiring ≥15 mm (Anaconda ≥20 mm), and Treovance, which is eligible for necks ≤75° with ≥15 mm length. Ovation's innovation of combining polymer-filled O-rings with integral anchors can treat conical necked AAAs giving Ovation iX and Alto an advantage. Short-necked AAAs can be treated with Alto, eligible for necks as short as 7 mm, and Endurant II, which can treat ≥10 mm necks or 4 mm if used in conjunction with the EndoAnchors system, respectively. Alto and Conformable report a 100% technical success rate, absence of AAA-related death, migration, ruptures, and limb occlusion during follow-up. Endurant II and Ovation iX report >99% technical success rate and are almost free from the AAA mortality rate, ruptures, migration, and limb occlusion, while Ovation iX has a high rate of sac dilation (15.5%) in a 5-year follow-up. Anaconda is slightly better than Aorfix and Treovance, which are related to the lowest technical success rates, 98.3%, 96.3%, and 96%, respectively. Aorfix has the highest AAA mortality rate, 4% in a 60 month follow-up.

Conclusion

Most new generation endografts described have comparable results. They broaden the eligibility of patients for EVAR due to their unique technical characteristics described. There is a lack of comparative studies for newer endografts and postmarket clinical studies with long-term results concerning the most recently approved devices described, Alto and Conformable.

"Aortic Balloon-Molding" (ABM) During Ovation Endograft Implantation Expands Graft Use for Hostile Neck Anatomy

BACKGROUND

Challenging aortoiliac anatomy such as short neck and narrow access vessels is responsible for EVAR ineligibility in up to 50% of cases. The Ovation stent-graft helped widen the range of AAAs suitable for EVAR thanks to its low-profile delivery system and polymer-filled sealing rings. However, its advantages are offset by a tight sizing chart that can lead to increased risk of type Ia endoleak or endograft infolding from under or oversizing, respectively. We sought to assess the safety and efficacy of a novel endovascular technique developed to expand the use of the Ovation endograft while avoiding these issues.

METHODS

We conducted a retrospective review of all patients who underwent EVAR with the Ovation endograft at our institution between March 2019 and December 2020. "Aortic Balloon Molding" or ABM is a novel endovascular technique in which the graft is pre-cannulated and a compliant aortic balloon is inflated at the site of the graft's sealing rings during polymer administration. The technique was preferentially performed in patients with hostile neck anatomy (HNA) defined as any or all of angulation>60°, reverse taper configuration, ≥50% circumferential thrombus or calcification. Patients undergoing traditional deployment were compared to those in whom ABM was performed. Endpoints included neck-related adjunctive procedures, technical success, type Ia endoleak at completion angiogram and 1-year freedom from type Ia endoleak and migration.

RESULTS

A total of 43 patients were included in the study, of which, 26 (60.5%) were treated with the ABM technique. Mean follow-up was 7.9±6 months. Patients in the ABM group were more likely to have a reverse taper neck (61.5% vs. 41.2%, P=0.1), to have significant circumferential thrombus or calcium (23.1% vs. 5.9%, P=0.1) and to be treated outside of the Ovation IFU regarding anatomic characteristics (65.4% vs. 41.2%, P=0.1). Technical success was achieved in 100% of cases. However, patients in the ABM group were less likely to require a neck-related adjunctive procedure (7.7% vs. 23.5%, P=0.1). Only one type Ia endoleak was observed at completion angiogram in a patient treated without ABM. At one-year, freedom from type Ia endoleak or migration was 100% for both groups.

CONCLUSIONS

Aortic Balloon Molding proves to be a safe and effective adjunctive technique for the treatment of AAAs with hostile neck anatomy using the Ovation stent-graft. This may allow optimal endograft sizing to achieve adequate seal in complex aortic anatomies. Further research is warranted to evaluate the long-term outcomes of this technique.

Profile of the Ovation ALTO abdominal stent graft for the treatment of abdominal aortic aneurysms: overview of its safety and efficacy

INTRODUCTION

The Ovation ALTO is the next generation aortic stent graft from Endologix for the treatment of infra-renal abdominal aortic aneurysms. The device uses polymer-injected rings to create a proximal seal at the aneurysm neck.

AREAS COVERED

Results from the first clinical study of the ALTO graft are analyzed and the potential benefits of the graft in minimizing post-treatment aneurysmal neck dilation discussed. The implications of the ALTO's Instructions-For-Use (IFU) and low-profile delivery system are also reviewed.

EXPERT OPINION

The re-positioning of the sealing rings higher on the graft and an integrated compliant balloon are the most significant improvements on the Ovation iX, facilitating accurate placement of the proximal sealing ring and prompt balloon dilation of the polymer rings. The expansion the IFU to include neck lengths of ≥7 mm will mean more patients are eligible for infra-renal EVAR within IFU with the ALTO device. The published data on the device to date is limited. With over 1000 implants worldwide we would hope for more published data to become available. If this demonstrates similar mid-term results to that seen with the Ovation iX in arguably more hostile neck anatomy, then the Ovation ALTO is likely to be more widely used.

Long-term results of low-profile stent grafts for treatment of infrarenal aortic aneurysms: Results from a retrospective multicenter registry

OBJECTIVE

In recent years, manufacturers have developed new stent grafts with lower profiles to increase the endovascular aneurysm repair applicability. As reported by the current European Society for Vascular Surgery guidelines, long-term evaluation of such low-profile platforms is strongly recommended. This study aims to report outcomes beyond 5 years from a multicenter registry, including a real-world cohort of patients electively treated with low-profile stent grafts.

METHODS

A retrospective data collection of patients who had undergone elective implantation of low-profile endograft ≤16 Fr. (Zenith LP, Ovation, Incraft) was performed in nine centers. The primary endpoint was a long-term primary clinical success. Secondary endpoints were survival rate, freedom from abdominal aortic aneurysm (AAA)-related death, freedom from type I to III endoleak, limb patency, and freedom from all reinterventions. The Kaplan-Meier curves were stratified for investigative devices. A multivariate analysis evaluated predictors of primary clinical success and reintervention rate.

RESULTS

A total of 619 patients were enrolled (Ovation, n = 373; Incraft, n = 111; and Zenith LP, n = 135), with a mean follow-up of 56.8 ± 22.8 months. The overall primary and the secondary clinical success rate at 8 years was 72.1% and 93.8%, respectively. At 8 years, overall survival was 53.2%, freedom from AAA-related death was 94.4%, freedom from reintervention was 74%, freedom from type I/III endoleak was 86.9%, and limb patency was 90.4%. A significantly worse primary clinical success of the Zenith LP was recorded as dependent on more limb-related events. No differences between platforms were registered in the rate of AAA-related deaths, open conversion, sac enlargement, and type I/III endoleaks (P = .26). Multivariate analysis identified iliac tortuosity (hazard ratio, 2.053) and Zenith LP (hazard ratio, 3.818) as significant independent predictors of clinical failure and reintervention.

CONCLUSION

Low-profile stent grafts have acceptable long-term outcomes. Overall survival and AAA-related death were in line with those reported for traditional devices. Long-term surveillance and reintervention, when necessary, remain crucial to guarantee durability.

ePTFE-based biomedical devices: An overview of surgical efficiency

Polytetrafluoroethylene (PTFE) is a ubiquitous material used for implants and medical devices in general because of its high biocompatibility and inertness: blood vessel, heart, table jawbone, nose, eyes, or abdominal wall can benefit from its properties in case of disease or injury. Its expanded version, ePTFE is an improved version of PTFE with better mechanical properties, which extends its medical applications. A material as frequently used as ePTFE with these exceptional properties deserves a review of its main uses, developments, and possibility of improvements. In this systematic review, we examined clinical trials related to ePTFE-based medical devices from the literature. Then, we excluded all trials using ePTFE as a control to test other devices. ePTFE-coated stents, hemodialysis and bypass grafts, guided bone and tissue regeneration membranes, hernia and heart repair and other devices are reviewed. The rates of success using these devices and their efficiency compared to other materials used for the same purposes are reported. ePTFE appears to be more or just as efficient compared to them. Some success rates remain low, suggesting the need of improvement ePTFE for medical applications.

Polymer based endografts have improved rates of proximal aortic neck dilatation and migration

BACKGROUND

Proximal aortic neck dilatation (PND) affects a considerable proportion of patients undergoing endovascular aneurysm repair (EVAR) and is associated with increased rates of type I endoleak (EL1), migration, and reinterventions. Although there are numerous studies investigating PND following the placement of endografts that utilize self-expanding stent (SES) technology, there are few reports for patients treated with endografts that utilize polymer-filled rings. The purpose of this study is to examine PND and graft migration after EVAR with the Ovation stent graft.

METHODS

The study comprised patients who underwent EVAR as part of the prospective, international, multicenter Ovation stent graft trial. A clinical events committee adjudicated adverse events through 1 year, an independent imaging core laboratory analyzed imaging through 5 years, and a data safety and monitoring board provided study oversight. Neck diameter was measured at the level of the lowest renal artery. PND was defined as neck enlargement of 3 mm or more. Graft migration was defined as distal movement >10 mm or movement ≤10 mm when resulting in secondary intervention.

RESULTS

A total of 238 patients received this device during the study period. Patients were predominantly male (81%), with a mean age of 73 ± 8 years. Median follow-up was 58 months (IQR 36-60). Almost half the patients (110 patients, 46%) had challenging anatomy; defined as outside the instructions for use (IFU) with other commercially available stent grafts. 41 patients (17.2%) had a proximal neck length <10 mm and 93 (39%) had a minimum access vessel diameter <6 mm. The technical success rate was 100%. The 1-, 3- and 5-year overall survival rates were 96.6%, 86.2% and 74.9%, respectively. The immediate postoperative proximal neck diameter ranged from 16 mm to 31 mm with a mean of 22.4 ± 3 mm. During follow-up, ten patients (4.2%) developed PND. Freedom from PND estimates at 1, 3 and 5 years were 97.7%, 96%, and 93.6%, respectively. None of the patients developed endograft migration.

CONCLUSIONS

The use of the Ovation stent graft was associated with low rates of PND despite challenging neck anatomy in 17% of patients. No graft migration was observed. The design of this endograft may explain its superiority to SES in preventing neck dilatation and migration even in patients with challenging neck anatomy. This is important, as we continue to see significant late failures of EVAR due to proximal neck degeneration.

The Polymer-Based Technology in the Endovascular Treatment of Abdominal Aortic Aneurysms

An abdominal aortic aneurysm (AAA) is a dilatation of the abdominal aorta that progressively grows until it ruptures. Treatment is typically recommended when the diameter is more than 5 cm. The EVAR (Endovascular aneurysm repair) is a minimally invasive procedure that involves the placement of an expandable stent graft within the aorta to treat aortic disease without operating directly on the aorta. For years, stent grafts' essential design was based on metallic stent frames to support the fabric. More recently, a polymer-based technology has been proposed as an alternative method to seal AAA. This review underlines the two platforms that are based on a polymer technology: (1) the polymer-filled endobags, also known as Endovascular Aneurysm Sealing (EVAS) with Nellix stent graft; and (2) the O-ring EVAR polymer-based proximal neck sealing device, also known as an Ovation stent graft. Polymer characteristics for this particular aim, clinical applications, and durability results are hereby summarized and commented critically. The technique of inflating endobags filled with polymer to exclude the aneurysmal sac was not successful due to the lack of an adequate proximal fixation. The platform that used polymer to create a circumferential sealing of the aneurysmal neck has proven safe and effective.

Morphological applicability of currently available stent grafts in the endovascular repair of asymptomatic abdominal aortic aneurysm in East-Central European patients

Introduction

Currently, there is a wide range of commercially available devices for endovascular aneurysm repair (EVAR) that differ in terms of both anatomical requirements and the technology and technique of deployment.

Aim

To assess the applicability of currently commercially available devices for EVAR in the treatment of an asymptomatic abdominal aneurysm (AAA).

Material and methods

The study group included 100 patients with infrarenal AAA with a maximum diameter ≥ 50 mm, qualified for invasive treatment at the University Hospital in 2013–2014. The aortoiliac morphological characteristics of the AAA were evaluated on preoperative computed tomography angiograms using the OsiriX DICOM viewer in the 3D-MPR mode. The morphological applicability of 14 types of CE-marked and FDA-approved stent grafts was determined based on their instructions for use (IFU).

Results

EVAR was feasible with at least one of the analysed devices in 68% of patients. The morphological applicability was as follows: Excluder Conformable (65%), Ovation iX (51%), Endurant II (47%), Treo (45%), Excluder C3 (45%), AFX 2 (45%), Incraft (44%), E-tegra (44%), Zenith Alfa (41%), Zenith Flex (40%), Anaconda (39%) Aorfix (37%), Altura (34%), and E-vita (20%). The differences in the stent graft applicability were statistically significant (p < 0.001). A wide diameter of the common iliac artery, angulated proximal neck, and diameter of proximal neck out of range constituted the most frequent causes of EVAR inapplicability.

Conclusions

The IFU-based applicability of currently available AAA stent graft systems differs significantly. Despite the constant evolution of EVAR technology, at least 32% of AAA will require a different therapeutic approach.

An update on the ovation abdominal stent graft for the treatment of abdominal aortic aneurysms: current evidence and future perspectives

Introduction: The Ovation stent-graft has presented satisfactory mid-term results in the management of abdominal aortic aneurysms (AAA). Its unique design with uncoupling of fixation and sealing and the lowest profile in the market has expanded the treatment in AAA with challenging neck anatomies and, especially, in the females presenting mostly with narrow iliac access vessels. Morever, a new design modification, the Ovation Alto was recently introduced in the Market, while certain off-label uses of the Ovation in treating either juxtarenal- or short-necked AAA have been proposed. Areas covered: Aim of this article was to present the current articles with the long-term results of the Ovation endograft and discuss the new developments and modifications in its use. Expert commentary: the Ovation stent-graft exhibits very satisfactory clinical long-term results in AAA treated within the instructions-for-use, expands significantly the treatment of AAA in females and overcomes reliably challenging anatomical issues of the infrarenal neck that would render these cases ineligible for treatment with any other endograft. Εxperience with the specific, unique technical features of Ovation as well as careful selection of patients and meticulous preoperative study of the AAA anatomy are key-elements to the successful performance of this endograft.

An update on the improvement of patient eligibility with the use of new generation endografts for the treatment of abdominal aortic aneurysms

PURPOSE

Endovascular aneurysm repair (EVAR), performed within device instructions for use (IFU), offers improved outcomes. New endograft designs attempt to increase eligibility rates of abdominal aortic aneurysm (AAA) patients treated within device IFU. We aim to examine the anatomic suitability of the Ovation endograft in our AAA patients and compare it with the other contemporary devices.

RESEARCH DESIGN AND METHODS

Three-hundred and seven consecutive elective AAA patients treated during a 5-year period were included. Patient-specific anatomic characteristics were based on endograft IFUs to determine eligibility rates of each system.

RESULTS

Two-hundred-twenty-five patients underwent EVAR and 82 open surgery. Ineligibility for device implantation was significantly lower for the Ovation iX system (32%) compared to other devices (AFX-2:49%, Altura:49%, Anaconda:54%, Endurant II:46%, Excluder:52%, Excluder Conformable:39%, Incraft:43%, E-Tegra:52%, Zenith-Alpha:52%; P-Value<0.001). The Alto system (next-generation Ovation) achieved an even lower ineligibility rate of 30% (P = 0.008). Short proximal aortic neck length followed by access vessel inadequacy were the primary reasons for ineligibility.

CONCLUSION

The Ovation-iX included more patients with anatomic characteristics within device IFUs resulting in improved eligibility rates compared with the rest of contemporary devices. Its evolution, the Alto system, further improves patient eligibility due to the inclusion of shorter aortic necks.

EXPERT OPINION

The Ovation iX system presented a significantly better performance and was eligible for use in a greater number of patients in our series of elective AAA repairs, accommodating patient-specific aortic anatomies. Of course, performing EVAR within the endograft's IFU is important to achieve optimal and durable outcomes. The proximal neck length followed by the size of the access vessels are the two more common factors resulting in loss of eligibility. Except for overall eligibility rates, a case by case decision must be made on which is the most suitable device for each patient, based on the specific characteristics of its unique anatomy.

Five-year results of the INSPIRATION study for the INCRAFT low-profile endovascular aortic stent graft system

OBJECTIVE

We present the 5-year results of a prospective regulatory study of the INCRAFT device, a low-profile endovascular stent graft system for repair of abdominal aortic aneurysms.

METHODS

This was an open-label prospective nonrandomized single-arm study enrolling in centers in the United States and Japan. The primary effectiveness outcome was successful aneurysm treatment and the primary safety outcome was the incidence of major adverse events at 30 days after the procedure. Major long-term outcomes were mortality, reintervention, adverse limb outcomes, and suprarenal stent fracture.

RESULTS

One hundred and ninety patients (mean age, 73.8 ± 7.6 years; 90% male; 69% white and 30% Asian) were enrolled from 32 centers throughout the United States and Japan. Minimal access vessel size was less than 7 mm on both sides in 43.9% of the study cohort. Thirty-day major adverse events occurred in 3.2% of patients (6/190). Periprocedural technical success was 94.1% (176/187). Successful aneurysm treatment was 100% at 30 days and 87.9% at 1 year. Two patients required open conversion for thromboembolic complications, 3 developed new type I or III endoleaks, and 7 experienced graft or limb occlusion. Freedom from graft occlusion was 96 ± 2% at 1 year and 94 ± 2% at 5 years. Freedom from stent fracture was 97 ± 1% at 1 year and 87 ± 3% at 5 years. Freedom from aneurysm-related mortality was 99 ± 1% at 1 and 5 years.

CONCLUSIONS

This study demonstrates good efficacy and safety and a very low rate of aneurysm related deaths with the INCRAFT device in a population with a high proportion of challenging anatomy.

Similar 5-year outcomes between female and male patients undergoing elective endovascular abdominal aortic aneurysm repair with the Ovation stent graft

OBJECTIVE

Female patients undergoing endovascular aneurysm repair (EVAR) for infrarenal abdominal aortic aneurysms present with more challenging anatomy and historically have worse outcomes compared with men. The Ovation Abdominal Stent Graft platform (Endologix, Irving, Calif) contains a polymer-filled proximal sealing ring and has a low-profile delivery system, potentially beneficial in female patients. We therefore investigated differences in long-term outcomes between men and women treated with this device.

METHODS

We used data collected prospectively in the Effectiveness of Custom Seal with Ovation: Review of the Evidence (ENCORE) database, comprising five trials and the European Post-Market Registry. Anatomic characteristics of the proximal aneurysm neck and iliac arteries were compared between male and female patients. Outcomes were 5-year freedom from type IA and type I/III endoleaks, abdominal aortic aneurysm-related reinterventions, and overall survival. We used Kaplan-Meier analysis to estimate survival proportions and tested univariate differences in survival using log-rank tests. Cox proportional hazards modeling was used to adjust for baseline differences.

RESULTS

We identified 1045 (81%) male and 251 (19%) female patients undergoing EVAR. Female patients were older (mean age, 75 ± 8.4 years vs 73 ± 8.1 years; P < .006). Aneurysm diameter (52 ± 7.5 mm vs 55 ± 9.2 mm; P < .001) and proximal neck diameter (21 ± 3.3 mm vs 23 ± 2.9 mm; P < .001) were smaller in female patients, but adjusted for body surface area, female patients had relatively larger aneurysms and aneurysm necks. Furthermore, female patients presented with shorter proximal necks, smaller iliac artery diameters, more angulated necks, and higher rates of reverse-tapered necks. Five-year freedom from type IA endoleak was similar between men and women (97% vs 96%; P = .38), as was freedom from type I/III endoleaks (91% vs 94%; P = .37) and reinterventions (91% vs 93%; P = .67). Five-year survival was 81% for female patients, similar to the 79% in male patients (P = .55), with one aneurysm-related death in female patients (0.4%) and five in male patients (0.8%; P = .76). Risk-adjusted analyses showed no association between sex and type IA endoleak (hazard ratio [HR], 1.4; 95% confidence interval [CI], 0.6-3.1; P = .41), type I/III endoleak (HR, 1.4; 95% CI, 0.7-2.8; P = .33), reintervention (HR, 1.0; 95% CI, 0.6-2.0; P = .77), and overall mortality (HR, 0.7; 95% CI, 0.4-1.1; P = .14).

CONCLUSIONS

Female patients undergoing EVAR with the Ovation platform presented with substantially more adverse proximal neck characteristics. Despite these differences, 5-year freedom from endoleaks and overall survival did not differ between sexes.