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

Sex Comparative Analysis of Branched and Fenestrated Endovascular Aortic Arch Repair Outcomes

OBJECTIVE

Female sex is a risk factor for adverse events after endovascular aortic repair. Sex comparative early and midterm outcomes of fenestrated and branched endovascular aortic arch repair (F/B-Arch) are presented.

METHODS

A single centre retrospective sex comparative analysis of consecutive patients managed with F/B-Arch was conducted according to STROBE. Primary outcomes were sex comparative technical success, death, and cerebrovascular morbidity at 30 days. Kaplan-Meier estimates were used for follow up outcomes.

RESULTS

Among 209 patients, 38.3% were women. Coronary artery disease (p < .001) and previous myocardial infarction (p = .001) were more common in women. Non-native proximal aortic landing was higher in women (women: 51.3%; men: 31.8%, p = .005) and the aortic dissection rate was lower (28.8% vs. 48.1%, p = .005). Proximal landing to Ishimaru zones showed no difference (zone 0: p = .18; zone 1: p = .47; zone 2: p = .39). Graft configurations were equally distributed. In total, 416 supra-aortic trunks were bridged. The median number of revascularisations per patient was two (interquartile range 1, 3), with no difference between sexes (p = .54). Technical success (women: 97.5%; men: 96.9%, p = .80), 30 day mortality rate (women: 10%; men: 9.3%, p = .86), and cerebrovascular morbidity (women: 11.3%; men: 17.1%, p = .25) were similar. Women presented more access related complications (women: 32.5%; men: 16.3%, p = .006), without affecting access related re-interventions (p = .55). Survival (women: 81.1%, 95% confidence interval [CI] 76.3 - 85.9%; men: 79.8%, 95% CI 76.0 - 83.6%) and freedom from re-intervention (women: 56.6%, 95% CI 50.4 - 62.8%; men: 55.3%, 95% CI 50.1 - 60.5%) at 12 months were similar (log rank, p = .40 and p = .41, respectively).

CONCLUSION

Both sexes presented similar outcomes after F/B-Arch. Appropriate patient selection may decrease the effect of sex in F/B-Arch outcomes.

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.

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%.

Disparities in reporting and representation by sex, race, and ethnicity in endovascular aortic device trials

OBJECTIVE

Vulnerable populations, including women and racial and ethnic minorities, have been historically underrepresented in clinical trials. We, therefore, studied the demographics of patients enrolled in pivotal endovascular aortic device trials in the United States.

METHODS

We queried the Food and Drug Administration (FDA) medical devices database for all FDA-approved endografts for the treatment of aortic aneurysms, transections, and dissections from September 1999 to November 2021. These included abdominal endovascular aortic repair (EVAR), thoracic EVAR (TEVAR), fenestrated EVAR (FEVAR) devices, and dissection stents. Multiple cases of approval for expanded indications were included separately. The primary outcomes included the proportion of trials reporting participant sex, race, and ethnicity and the proportion of enrolled participants across sex, racial, and ethnic groups.

RESULTS

The FDA provided 29 approvals from 29 trials of 24 devices: 15 EVAR devices (52%), 12 TEVAR devices (41%), 1 FEVAR device (3.4%), and 1 dissection stent (3.4%). These trials had included 4046 patients. Of the 29 trials, all had reported on the sex of the participants, and the median female enrollment was 21% (interquartile range [IQR], 11%-34%). The EVAR trials had the lowest female enrollment (11%; IQR, 8.7%-13%) compared with 41% (IQR, 27%-45%) in the TEVAR trials, 21% in the FEVAR trial, and 34% in the dissection stent trial (P < .01 for the difference). Only 52% of the trials had reported the three most common racial groups (White, Black, Asian), and only 48% had reported Hispanic ethnicity. The TEVAR trials were the most likely to report all three racial groups and Hispanic ethnicity (92% and 75%, respectively), while the EVAR trials had the lowest reporting rates (13% and 20%, respectively). Where reported, the median enrollment of racial and ethnic groups across the trials was as follows: Black patients, 9.8% (FEVAR, 0%; EVAR, 1.9%; TEVAR, 12%; dissection stent, 25%; P = .01); Asian patients, 2.4% (EVAR, 0.6%; FEVAR, 2.4%; TEVAR, 2.5%; dissection stent, 11%; P = .24); and Hispanic patients, 3.8% (EVAR, 1.3%; FEVAR, 2.4%; TEVAR, 3.9%; dissection stent, 4.1%; P = .75).

CONCLUSIONS

Racial and ethnic minority groups were underrepresented and underreported in pivotal aortic device trials that led to FDA approval. Female patients were also underrepresented in these aortic trials, especially for EVAR. These data suggest the need for standardization of reporting practices and minimum thresholds for minority and female participation in pivotal trials to promote equitable representation.

Gender Influence on Abdominal Aortic Aneurysm Surgery in a Caribbean Population

Female patients with abdominal aortic aneurysms (AAAs) are usually less common and older than their male counterparts. We report on AAA disease in a Caribbean nation with respect to gender and review their outcomes relative to the male population. Data were collected prospectively and analyzed retrospectively for patients with AAAs who underwent surgery from 2001 to 2018. Sixty patients were diagnosed with AAA with 44 going on to have surgical repair of which 35 were males, aged 61 to 89 (mean age 73.4 years). Nine women ages 44 to 74 years (mean age 60.8 years) had surgical intervention, three being between 40 and 49 years. The size of aneurysms in these patients ranged from 4.3 to 11.0 cm in diameter (average 6.95 cm), female patients having an average diameter of 6.7 cm. Of the 44 patients, 43 underwent open and one endovascular repair. Thirty-three were elective cases and 11 were ruptured with 32 aorto-aortic and 13 aorto-iliac repairs. There were nine fatalities, three elective and six ruptured, with only one being female. Women had similar outcomes to men in all age groups with young patients having good results. Female AAA patients are usually older, undergo less surgical procedures especially if endovascular, and have worse outcomes than their male counterparts. Our study showed that the females were younger but had similar outcomes to the male patients. The female Caribbean patients may present at much younger ages than in continental populations and this may be due to genetic, ethnic, or lifestyle factors.

"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.

Female Sex Is Associated With Reintervention and Mortality Following Elective Endovascular Abdominal Aortic Aneurysm Repair

OBJECTIVE

While sex differences in endovascular abdominal aortic aneurysm repair (EVAR) outcomes are increasingly reported, but contributing factors remain without consensus. We investigated disparities in sex-specific outcomes following elective EVAR at our institution and evaluated factors that may predispose females to increased morbidity and mortality.

METHODS

A retrospective chart review of all patients undergoing elective EVAR from 2011 to 2020 at a suburban tertiary care center was performed. The primary outcomes were five-year survival and freedom from reintervention. Fisher's exact test, t-tests, and Kaplan-Meier analysis using the rank-log test investigated associations between sex and outcomes. A multivariable Cox proportional hazard model controlling for age and common comorbidities evaluated the effect of sex on survival and freedom from reintervention.

RESULTS

Two hundred and seventy-three patients underwent elective EVAR during the study period, including 68 (25%) females and 205 (75%) males. Females were older on average than males (76 years vs. 73 years, p= <0.01) and were more likely to have chronic obstructive pulmonary disease (COPD; 38% versus 23%, p=0.01), require home oxygen therapy (9% versus 2%, p=0.04) or dialysis preoperatively (4% versus 0%, p=0.02). Distribution of other common vascular comorbidities was similar between the sexes. Thirty-day readmission was greater in females than males (18% versus 8%, p=0.02). Females had significantly lower survival at five years (48% ± 7.9% versus 65% ± 4.3%, p<0.01) and significantly lower one-year (89% ± 4.1% for females vs. 94% ± 1.7% for males, p=0.01) and five-year freedom from reintervention (69% ± 8.9% versus 84% ± 3.3%, p=0.02). On multivariable analysis, female sex (hazard ratio [HR]: 1.8, 95% confidence interval [CI]: 1.1-2.9), congestive heart failure (HR: 2.2, 95% CI: 1.2-3.9) and age (HR: 1.1, 95% CI: 1.0-1.1) were associated with 5-year mortality. Female sex remained as the only variable with a statistically significant association with five-year reintervention (HR: 2.4, 95% CI: 1.1-4.9).

CONCLUSIONS

Female sex was associated with decreased five-year survival and increased one and five-year reintervention following elective EVAR. Data from our institution suggests factors beyond patient age and baseline health risk likely contribute to greater surgical morbidity and mortality for females following elective EVAR.

One-Year Results of the INSIGHT Study on Endovascular Treatment of Abdominal Aortic Aneurysms

OBJECTIVE

Endovascular repair of abdominal aortic aneurysms (AAA) using the INCRAFT™ AAA Stent Graft System was safe and effective in regulatory approval studies. We herein report on the 1-year results of a real-world clinical study.

METHODS

The INSIGHT study is a multi-center, prospective, open label, post-approval study conducted to continually evaluate the safety and performance of the INCRAFT ™ System. Between 2015 and 2016, 150 consecutive patients with AAA at 23 centers in Europe were treated with the device in routine clinical practice. The primary endpoint was freedom from major adverse events (MAEs), namely death, myocardial infarction (MI), cerebrovascular accident (CVA) and renal failure, within 30 days of the index procedure. Endpoint data were assessed by a core laboratory. The secondary endpoints included technical success at the conclusion of the procedure and clinical success.

RESULTS

All 150 patients studied (mean age: 73.6 ± 8.0 and 89.3% men) met the primary endpoint without MAEs at 30-day follow up. Technical success was achieved in 99.3% of patients without stent fractures at 30 days. Among the 146 patients eligible for 1-year follow-up, the MAE rate was 8.2%, i.e., 12 patients suffered 13 MAEs: CVA in 8, MI in 1, and 4 died (resulting in a 2.7% all-cause mortality rate). There were no reports of new onset renal failure requiring dialysis. Only 2.7% of patients had type I endoleak and no III endoleaks were identified through 1 year. The rate of clinical success at 1 year was 91.8%.

CONCLUSIONS

The 1-year results of this multicenter real-world study underscore the safety and effectiveness of endovascular treatment of AAA with the INCRAFT System in routine clinical practice.

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.

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.

Editor's Choice - Systematic Review and Meta-Analysis of Sex Specific Differences in Adverse Events After Open and Endovascular Intact Abdominal Aortic Aneurysm Repair: Consistently Worse Outcomes for Women

OBJECTIVE

Previously, reports have shown that women experience a higher mortality rate than men after elective open (OAR) and endovascular (EVAR) repair of abdominal aortic aneurysm (AAA). With recent improvements in overall AAA repair outcomes, this study aimed to identify whether sex specific disparity has been ameliorated by modern practice, and to define sex specific differences in peri- and post-operative complications and pre-operative status; factors which may contribute to poor outcome.

METHODS

This was a systematic review, meta-analysis, and meta-regression of sex specific differences in 30 day mortality and complications conducted according to PRISMA guidance (Prospero registration CRD42020176398). Papers with ≥ 50 women, reporting sex specific outcomes, following intact primary AAA repair, from 2000 to 2020 worldwide were included; with separate analyses for EVAR and OAR. Data sources were Medline, Embase, and CENTRAL databases 2005 - 2020 searched using ProQuest Dialog.

RESULTS

Twenty-six studies (371 215 men, 65 465 women) were included. Meta-analysis and meta-regression indicated that sex specific odds ratios (ORs) for 30 day mortality were unchanged from 2000 to 2020. Mortality risk was higher in women for OAR and more so for EVAR (OR [95% CI] 1.49 [1.37 - 1.61]; 1.86 [1.59 - 2.17], respectively) and this remained following multivariable risk adjustment. Transfusion, pulmonary complications, and bowel ischaemia were more common in women after OAR and EVAR (OAR: ORs 1.81 [1.60 - 2.04], 1.40 [1.28 - 1.53], 1.54 [1.36 - 1.75]; EVAR: ORs 2.18 [2.08 - 2.29] 1.44 [1.17 - 1.77], 1.99 [1.51 - 2.62], respectively). Arterial injury, limb ischaemia, renal and cardiac complications were more common in women after EVAR (ORs 3.02 [1.62 - 5.65], 2.13 [1.48 - 3.06], 1.46 [1.22 - 1.72] and 1.19 [1.03 - 1.37], respectively); the latter was associated with greater mortality risk on meta-regression.

CONCLUSION

Increased mortality risk for women following AAA repair remains. Women had a higher incidence of transfusion, pulmonary and bowel complications after EVAR and OAR. Higher mortality risk ratios for EVAR may result from cardiac complications, additional arterial injury, and embolisation, leading to renal and limb ischaemia. These findings indicate possible causes for observed outcome disparities and targets for quality improvement.

Excluder Stent Graft-Related Outcomes in Patients with Aortic Neck Anatomy Outside of Instructions For Use (IFU) within the Global Registry for Endovascular Aortic Treatment (GREAT): Mid-term Follow-Up Results

BACKGROUND

The utilisation rate of endovascular aortic aneurysm repair has increased continuously over the past 2 decades. Endovascular aortic aneurysm repair is still performed frequently in patients with an unfavourable proximal seal zone, despite the associated late complications.

PURPOSE

We aimed to evaluate the mid-term durability of the GORE® EXCLUDER® AAA Endoprosthesis, featuring the C3 delivery system, in patients with a proximal neck anatomy outside the instructions for use (IFU).

METHODS

A retrospective sub-analysis of the Global Registry for Endovascular Aortic Treatment including patients treated for abdominal aortic aneurysms with the GORE EXCLUDER AAA Endoprosthesis (W.L. Gore & Associates, Inc, Flagstaff, Arizona) was performed. A "challenging neck" was defined as those treated outside the IFU with an aortic neck length <15 mm and/or aortic neck angle >60°. Cox proportional analyses were used to test for time-to-event differences between those treated within and outside the IFU while accounting for covariates, specifically proximal neck length and neck angle. The main outcomes assessed were 5-year all-cause mortality, 5-year endoleak development (type I or III), and 5-year device-related reinterventions.

FINDINGS

Of the 3,324 patients included in the analysis, 411 (12.4%) had a challenging neck and 2,913 (87.6%) did not. The patients in the challenging neck group were significantly older (74.9 years vs. 73.2 years, p≤0.0001) and had a significantly larger aortic aneurysm diameter at the time of the intervention than those treated within the IFU (61.2 mm vs. 56.4 mm, P< 0.0001), shorter proximal neck length (18 mm vs. 30 mm, P< 0.0001) and larger infrarenal neck angle (60.8° vs. 25.8°, P< 0.0001). In the multivariate analysis, brachial access site and challenging neck were not independent risk factors; increased age was associated with a shorter time to mortality (hazard ratio 1.051, 95% confidence interval 1.039-1.062, P< 0.0001), as was the use of tobacco (hazard ratio 1.329, 95% confidence interval 1.124-1.571, P= 0.0009). The 5-year all-cause mortality (36.2% vs. 27.5%, P= 0.002) and aorta-related mortality (3.8% vs. 1.1%, P= 0.002) were significantly higher in the challenging neck group. The risk of death within 5 years also increased significantly at 1.1% per millimetre increase in the abdominal aortic aneurysm diameter (P= 0.0005). Furthermore, the rates of type Ia endoleak development (7% vs. 1.2%, P< 0.001) and requirement for reintervention (13.3% vs. 9.7%, P< 0.001) were higher in those treated outside the IFU (challenging neck group).

CONCLUSIONS

Treatment with the Excluder AAA Endograft outside the IFU was associated with higher 5-year mortality values, increased type Ia endoleak development rates, and a greater need for reintervention compared with treatment within the IFU. This reiterates that fenestrated and open treatments should be strongly considered in cases with aortic neck anatomies outside the IFU. Infrarenal endovascular intervention outside the IFU should only be used when there is no alternative, with meticulous procedural planning and intervention to promote satisfactory outcomes.

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.

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.

Retroperitoneal iliac conduits as an alternative access site for endovascular aortic repair: a tertiary care center experience

Background

Retroperitoneal open iliac conduits (ROIC) are used in patients with hostile iliac anatomy undergoing endovascular aortic repair (EVAR).

Objectives

We hereby report our experience of ROIC in patients subjected to EVAR.

Methods

This was a retrospective evaluation of 8 patients out of a total of 75 patients (11%) who underwent EVAR in the last 10 years. Pre-procedure computed tomography angiography was used to assess the dimensions of iliac and femoral arteries. Patients who had small arterial dimensions (i.e. smaller than the recommended access size for the aortic endograft device) were subjected to ROIC.

Results

The mean age of the 3 males and 5 females studied was 45.7 ± 15.2 years. The indication for ROIC was the small caliber ilio-femoral access site in 7 patients and atherosclerotic disease in 1 patient. All external grafts were anastomosed to the right common iliac artery except one which was anastomosed to the aortic bifurcation site because of a small common iliac artery. The procedural success rate was 100%. Local access site complications included infection (n=1), retroperitoneal hematoma (n=1), and need for blood transfusion (n=3). The median post-intervention hospital stay was 10 days. All patients had favorable long-term outcomes at a median follow-up of 18 months.

Conclusions

Female patients require ROIC during EVAR more frequently. Adjunctive use of iliac conduit for EVAR was associated with favorable perioperative and short-term outcomes.

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.