Female Sex and Outcomes after Endovascular Aneurysm Repair for Abdominal Aortic Aneurysm: A Propensity Score Matched Cohort Analysis

Editor's Choice -- European Society for Vascular Surgery (ESVS) 2024 Clinical Practice Guidelines on the Management of Abdominal Aorto-Iliac Artery Aneurysms

OBJECTIVE

The European Society for Vascular Surgery (ESVS) has developed clinical practice guidelines for the care of patients with aneurysms of the abdominal aorta and iliac arteries in succession to the 2011 and 2019 versions, with the aim of assisting physicians and patients in selecting the best management strategy.

METHODS

The guideline is based on scientific evidence completed with expert opinion on the matter. By summarising and evaluating the best available evidence, recommendations for the evaluation and treatment of patients have been formulated. The recommendations are graded according to a modified European Society of Cardiology grading system, where the strength (class) of each recommendation is graded from I to III and the letters A to C mark the level of evidence.

RESULTS

A total of 160 recommendations have been issued on the following topics: Service standards, including surgical volume and training; Epidemiology, diagnosis, and screening; Management of patients with small abdominal aortic aneurysm (AAA), including surveillance, cardiovascular risk reduction, and indication for repair; Elective AAA repair, including operative risk assessment, open and endovascular repair, and early complications; Ruptured and symptomatic AAA, including peri-operative management, such as permissive hypotension and use of aortic occlusion balloon, open and endovascular repair, and early complications, such as abdominal compartment syndrome and colonic ischaemia; Long term outcome and follow up after AAA repair, including graft infection, endoleaks and follow up routines; Management of complex AAA, including open and endovascular repair; Management of iliac artery aneurysm, including indication for repair and open and endovascular repair; and Miscellaneous aortic problems, including mycotic, inflammatory, and saccular aortic aneurysm. In addition, Shared decision making is being addressed, with supporting information for patients, and Unresolved issues are discussed.

CONCLUSION

The ESVS Clinical Practice Guidelines provide the most comprehensive, up to date, and unbiased advice to clinicians and patients on the management of abdominal aorto-iliac artery aneurysms.

Long-Term Outcome of Intact Abdominal Aortic Aneurysm After Endovascular or Open Repair

OBJECTIVE

Endovascular aortic aneurysm repair (EVAR) has been established as a standard treatment option for intact abdominal aortic aneurysm (iAAA) and gained importance due to a lower perioperative mortality than open repair (OAR). However, whether this survival advantage can be maintained or if OAR is beneficial in terms of long-term complications and reinterventions remains questionable.

DESIGN

In this retrospective cohort study data from patients undergoing elective EVAR or OAR for iAAAs in the years 2010-2016 was analyzed. The patients were followed through 2018.

METHODS

In the propensity score matched cohorts the perioperative and long-term outcomes of the patients were assessed. We identified 20 683 patients undergoing elective iAAA repair (76.4% EVAR). The propensity matched cohorts included 4886 pairs of patients.

RESULTS

The perioperative mortality was 1.9% for EVAR and 5.9% for OAR (P = <.001). The perioperative mortality was mainly influenced by patients age (Odds-Ratio (OR):1.073, confidence interval (CI):1.058-1.088, P ≤ .001) and OAR (OR:3.242, CI:2.552-4.119, P ≤ .001). The early survival benefit after endovascular repair persisted for approximately 3 years (estimated survival EVAR 82.3%, OAR 80.9%, P = .021). After that time the estimated survival curves were similar. After 9 years the estimated survival was 51.2% after EVAR as compared to 52.8% after OAR (P = .102). The operation method didn't influence long-term survival significantly (Hazard-Ratio (HR): 1.046, CI: .975-1.122, P = .211). The vascular reintervention rate was 17.4% in the EVAR cohort and 7.1% in the OAR cohort (P ≤ .001).

CONCLUSION

EVAR has a significantly lower perioperative mortality than OAR, a survival benefit that lasts up to 3 years after intervention. Thereafter, no significant difference in survival was observed between EVAR and OAR. The decision between EVAR or OAR may depend on patient preference, surgeons' experience, and the institutions' ability to handle complications.

Women with large intact abdominal aortic aneurysms remain untreated

OBJECTIVE

A lower elective repair rate among women with abdominal aortic aneurysms (AAAs) has been a consistent finding. Reasons behind this gender gap have not been thoroughly outlined.

METHODS

This was a retrospective multicenter cohort study (ClinicalTrials.gov: NCT05346289) at three European vascular centers in Sweden, Austria and Norway. Patients in surveillance with AAAs were consecutively identified starting from January 1, 2014, until reaching a total sample size of 200 women and 200 men. All individuals were followed for 7 years through medical records. Final treatment distributions and the proportion of "truly untreated" (surgically untreated despite reaching guideline-directed thresholds: 50 mm for women and 55 mm for men) were determined. In a complementary analysis, a universal 55-mm threshold was used. Gender-specific primary reasons behind untreated statuses were clarified. Eligibility for endovascular repair among the truly untreated was assessed in a structured computed tomography analysis.

RESULTS

Women and men had similar median diameters at inclusion (46 mm; P = .54) and at treatment decisions (55 mm; P = .36). After 7 years, the repair rate was lower among women (47% vs 57%). More women were truly untreated (26% vs 8%; P < .001) despite similar mean ages as for male counterparts (79.3 years; P = .16). With the 55-mm threshold, 16% women still classified as truly untreated. Similar reasons for nonintervention were captured for women and men (50% due to comorbidities alone, 36% morphology and comorbidity). The endovascular repair imaging analysis revealed no gender differences. Among truly untreated women, ruptures were common (18%), and mortality was high (86%).

CONCLUSIONS

Surgical AAA management differed between women and men. Women could be underserved in terms of elective repairs: one in every four women was untreated with over-the-threshold AAAs. The lack of obvious gender differences in eligibility analyses could imply unmeasured discrepancies (eg, in disease extent or patient frailty).

Long-term Mortality and Reintervention After Endovascular and Open Abdominal Aortic Aneurysm Repairs in Australia, Germany, and the United States

OBJECTIVE

To examine long-term outcomes after endovascular (EVAR) and open repairs (OAR) for intact abdominal aortic aneurysms in Australia, Germany, and the United States, using a unified study design.

BACKGROUND

Similarities and differences in long-term outcomes after EVAR versus OAR across countries remained unclear, given differences in designs across existing studies.

METHODS

We identified patients aged >65 years undergoing intact abdominal aortic aneurysm repairs during 2010-2017/2018. We compared long-term patient mortality and reintervention after EVAR and OAR using Kaplan-Meier analyses and Cox regressions. Propensity score matching was performed within each country to adjust for differences in baseline patient characteristics between procedure groups.

RESULTS

We included 3311, 4909, and 145363 patients from Australia, Germany, and the United States, respectively. The median patient age was 76 to 77 years, and most patients were males (77%-84%). Patient mortality was lower after EVAR than OAR within the first 60 days and became similar at 3-year follow-up (Australia 14.7% vs 16.5%, Germany 18.2% vs 19.7%, United States: 24.4% vs 24.4%). At the end of follow-up, patient mortality after EVAR was higher than OAR in Australia [ hazard ratio (HR) 95% CI: 1.21 (0.96-1.54)] but similar to OAR in Germany [HR 95% CI: 0.92 (0.80-1.07)] and the United States [HR 95% CI: 1.02 (0.99-1.05)]. The risk of reintervention after EVAR was more than twice that after OAR in Australia [HR 95% CI: 2.60 (1.09-6.15)], Germany [HR 95% CI: 4.79 (2.56-8.98)], and the United States [HR 95% CI: 2.67 (2.38-3.00)]. The difference in reintervention risk appeared early in German and United States patients.

CONCLUSIONS

This multinational study demonstrated important similarities in long-term outcomes after EVAR versus OAR across 3 countries. Variation in long-term mortality and reintervention comparisons indicates possible differences in patient profiles, surveillance, and best medical therapy across countries.

Early and Mid-Term Outcomes of Females Treated with t-Branch off the Shelf Device

BACKGROUND

Female sex has been characterized as a risk factor of increased mortality in patients managed for complex aortic aneurysm using endovascular means. This study aimed to present the perioperative and follow-up outcomes of females managed electively or urgently with the t-Branch device and investigate factors affecting the early outcomes.

METHODS

A 2-center retrospective observational study was conducted including elective and urgent female patients managed with the t-Branch device (Cook Medical, Bjaeverskov, Denmark) for thoracoabdominal and pararenal aneurysms between January 1, 2018 and September 30, 2020. Primary early outcomes included technical success and 30-day mortality and morbidity [spinal cord ischemia (SCI) and acute kidney injury]. Follow-up survival and freedom from reintervention rates were assessed using Kaplan-Meier estimates.

RESULTS

In total, 153 females were included; 81 (52.9%) treated urgently. Urgent patients were older (73.2 ± 8.6 vs. 68.5 ± 6.8 years; P < 0.001) and presented higher previous coronary angioplasty/stenting (16.0% vs. 5.6%, P = 0.005) and lower double antiplatelet therapy (DAPT, 46.3% vs. 53.7%, P = 0.04) rates. Technical success was 97.4%. Early mortality was 16.3% (22% in urgent; 12% in elective; P = 0.2) and SCI and acute kidney injury were diagnosed in 13.7% (11% in urgent; 16% in elective; P = 0.2) and 18.3% (22.2% in urgent; 13.9% in elective; P = 0.18), respectively. Multivariate regression analyses showed that DAPT and b-blockers were related to lower 30-day mortality. DAPT was also preventive for SCI. Survival rates were 68.4% [standard error (SE) 0.07] at 12 months for the urgent and 75.6% (SE 0.09) at 24 months for the elective group (P = 0.14). Freedom from reintervention rates were 81.4% (SE 0.06) at 6 months and 64.7% (SE 0.09) at 18 months for the urgent and 81.7% (SE 0.06) at 6 months and 75.4% (SE 0.081) at 18 months for the elective group (P = 0.94).

CONCLUSIONS

Female patients managed with the t-Branch device for thoracoabdominal and pararenal aneurysms in elective and urgent setting presented similar 30-day mortality and SCI rates.

Investigation of Renal Decline and New Onset Dialysis Following Endovascular Aneurysm Repair in the Vascular Quality Initiative

INTRODUCTION

The purpose of this study is to identify variables significantly associated with renal function decline after elective endovascular infra-renal abdominal aortic aneurysm repair and to identify the rate and risks of subsequent progression to dialysis. Specifically, we investigate the long-term impact of supra-renal fixation, female gender, and physiologically stressful perioperative events on renal function following endovascular aneurysm repair (EVAR).

METHODS

Review of all EVAR cases in the Vascular Quality Initiative between 2003 and 2021 was conducted to investigate variable associations with three primary outcomes: postoperative acute renal insufficiency (ARI); greater than 30% decline in glomerular filtration rate (GFR) in patients beyond 1 year of follow up; and new onset dialysis requirement at any point in follow up. Binary logistic regression analysis was performed for the events of acute renal insufficiency and new onset dialysis requirement. Cox proportional hazard regression was performed regarding long term GFR decline.

RESULTS

Postoperative ARI occurred in 3.4% (1692/49 772) of patients. Significant (P < .05) association with postoperative ARI was noted for: age (OR 1.014/year, 95% CI 1.008-1.021); female gender (OR 1.44, 95% CI 1.27-1.67); hypertension (OR 1.22, 95% CI 1.04-1.44); chronic obstructive pulmonary disease (OR 1.34, 95% CI 1.20-1.50); anemia (OR 4.24, 95% CI 3.71-4.84); reoperation at index admission (OR 7.86, 95% CI 6.47-9.54); baseline renal insufficiency (OR 2.29, 95% CI 2.03-2.56); larger aneurysm diameter; increased blood loss; and higher volumes of intra-operative crystalloid. Risk factors (P < .05) correlating with a decline of 30% in GFR at any time beyond 1 year were: female gender (HR 1.43, 95% CI 1.24-1.65); body mass index (BMI) less than 20 (HR 1.34, 95% CI 1.03-1.74); hypertension (HR 1.38, 95% CI 1.15-1.64); diabetes (HR 1.34, 95% CI 1.17-1.53); COPD (HR 1.21, 95% CI 1.07-1.37); anemia (HR 1.92, 95% CI 1.52-2.42); baseline renal insufficiency (HR 1.31, 95% CI 1.15-1.49); absence of discharge ace-inhibitor (HR 1.27, 95% CI 1.13-1.42); long term re-intervention (HR 2.43, 95% CI 1.84-3.21) and larger AAA diameter. Patients who experienced long term GRF decline had a significantly higher long-term morality. New onset dialysis following EVAR occurred in .47% (234/49 772) of those meeting inclusion criteria. Higher rate (P < .05) of new onset dialysis was associated with age (OR 1.03/year, 95% CI 1.02-1.05); diabetes (OR 1.376, 95% CI 1.005-1.885); baseline renal insufficiency (OR 6.32, 95% CI4.59-8.72); Reoperation at index admission (OR 2.41, 95% CI 1.03-5.67); postoperative ARI (OR 23.29, 95% CI 16.99-31.91); absence of beta blocker (OR 1.67, 95% CI 1.12-2.49); long term graft encroachment on renal arteries (OR 4.91, 95% CI 1.49-16.14).

CONCLUSIONS

New onset dialysis following EVAR is a rare event. Perioperative variables influencing renal function following EVAR include blood loss, arterial injury, and reoperation. Supra-renal fixation is not associated with postoperative acute renal insufficiency or new onset dialysis in long term follow up. Renal protective measures are recommended for patients with baseline renal insufficiency undergoing EVAR as acute renal insufficiency following EVAR portends a 20-fold increased risk of new onset dialysis in long term follow up.

Sex difference in early mortality after abdominal aortic aneurysm repair

OBJECTIVE

Although female patients have a lower prevalence of abdominal aortic aneurysm (AAA), they seem to have a worse treatment outcome compared with male patients. Both maximum aneurysm diameter and aortic size index (ASI) are important indicators of the risk of AAA rupture, among which ASI has been shown capable of equalizing sex-related anatomical differences. Our study aimed to investigate whether sex is an independent risk factor for early postoperative mortality and how the diameter or ASI affects the association between sex and mortality.

METHODS

We performed a retrospective analysis of patients who enrolled in the AAA registry of the German Society of Vascular Surgery from 2013 to 2019. The patients were treated by either open surgical repair (OSR) or endovascular aneurysm repair (EVAR). The association between sex and 30-day mortality was investigated using logistic regression analysis. The interaction and mediating effects of maximum aneurysm diameter and ASI were investigated to verify their roles in the effect of sex on mortality. The relationships between the diameter (or ASI) and the risk of 30-day mortality in different sexes were demonstrated by the restricted cubic spline.

RESULTS

Overall, 23,275 cases were included in our analysis, with 20,130 male (86.5%) and 3139 female (13.5%) patients. Female patients had a smaller maximum aneurysm diameter (OSR, 55.23 ± 10.29 mm vs 58.05 ± 11.28 mm [P < .001]; EVAR, 54.06 ± 9.08 mm vs 56.11 ± 9.38 mm [P < .001]), but a higher ASI (OSR, 3.16 ± 0.71 vs 2.92 ± 0.69 [P < .001]; EVAR, 3.05 ± 0.66 vs 2.80 ± 0.59 [P < .001]) compared with male patients. The 30-day mortality rate was higher for female patients in both OSR (6.6% vs 4.2%; P = .002) and EVAR groups (1.8% vs 0.8%; P < .001). Logistic regression confirmed a significantly higher risk of 30-day mortality for female patients compared with male patients (odds ratio, 1.55; 95% confidence interval, 1.21-1.99; P = .001). No interaction was found between sex and diameter or ASI, but there were mediating effects for diameter and ASI in the effect of sex on 30-day mortality. For female patients, the risk of 30-day mortality linearly increased with the increase of diameter (P_Nonlinear = .089) or ASI (P_Nonlinear = .888), whereas the risk for male patients was U-shaped (for diameter, P_Nonlinear < .001; for ASI, P_Nonlinear = .020).

CONCLUSIONS

Sex is an independent risk factor for 30-day mortality after AAA repair. Both diameter and ASI are mediating factors for the effect of sex on 30-day mortality. The relationship between diameter or ASI and the risk of 30-day mortality is different for male and female patients.

Predictors of Decline in Renal Function 5 Years after EVAR

INTRODUCTION

While there exists copious short-term data regarding renal function following infra-renal endovascular abdominal aortic aneurysm repair (EVAR), long-term analysis is sparse. This is a single institution retrospective review of predictors of renal function decline 5 years after elective EVAR.

METHODS

All EVAR between 2007 and 2015 were queried. Patients in whom renal function was documented 5 years postoperatively were included in analysis. Exclusion criteria were ruptured aneurysm, mortality before 56 months, lack of follow-up, ESRD status, and concomitant renal intervention. The primary outcome investigated was a 20% or greater drop in glomerular filtration rate (GFR) 5 years postoperatively. The following variables at the time of surgery were investigated as potential predictors: age, gender, hypertension, hyperlipidemia, diabetes, CAD or prior MI, COPD, prior stroke, baseline eGFR under 60 mL/min/1.73 m², supra-renal fixation, infra-renal fixation, neck diameter, neck length, and number of contrast CT.

RESULTS

354 EVAR were identified of which 143 met inclusion criteria (211 excluded). Univariate analysis revealed female gender (OR 2.7), hypertension (OR 9.4), baseline renal insufficiency (OR 3.8), larger neck diameter, and supra-renal fixation (OR 2.32) all predictive (P < .05) of GFR drop at 5 years. Multivariate binary logistic regression analysis found female gender (multivariate OR 3.9, P = .023) and baseline renal insufficiency (multivariate OR 3.0, P = .029) as significant predictors of greater than 20% GFR drop at 5 years. Only 2 patients of the 143 progressed to dialysis requirement at 5 years.

CONCLUSIONS

Females and patients with baseline renal insufficiency are more vulnerable to significant decline in renal function 5 years following EVAR. Consistent with analogous literature, supra-renal fixation appears moderately deleterious toward renal function with no clinical significance in those with baseline normal renal function. The potential benefit of avoidance of supra-renal fixation in female patients with baseline renal insufficiency is worth further investigation in a more robust multi-center study.

Endovascular aortic repair is a cost-effective option for in-hospital patients with abdominal aortic aneurysm

BACKGROUND

To investigate the cost-effectiveness of endovascular aortic repair (EVAR) versus open aortic repair (OAR) for abdominal aortic aneurysm (AAA) using incremental costs per decreased in-hospital mortality rate gained through our patients' cohort.

METHODS

Medical records and healthcare costs of patients with AAA hospitalized between 2010 and 2015 were extracted from the National Health Insurance Research Database (NHIRD) of Taiwan. Multiple regression analysis was applied to adjust for confounding factors and to compare the differences in postoperative clinical outcomes between patients who received EVAR and OAR. The incremental cost-effectiveness ratio (ICER) of EVAR was determined based on the healthcare cost obtained from the analyzed data.

RESULTS

A total of 2803 AAA patients were identified (n = 559 with ruptured AAA and n = 2244 unruptured AAA). Patients with ruptured AAA who underwent EVAR compared with OAR patients had shorter hospital and intensive care unit (ICU) stays (all p < 0.05). For patients with unruptured AAA, those who received EVAR compared with OAR, the adjusted odds ratio (aOR) of postoperative complications and in-hospital mortality were 0.371 and 0.447 (all p < 0.05). The total direct surgical costs and medical expenses during hospitalization in all AAA patients were higher for the EVAR group; however, ICER was <1 per capita gross domestic product. Stratification by age groups further suggested that ICER for patients with unruptured AAA who received EVAR, compared with OAR, decreased with age.

CONCLUSION

Total direct medical costs were higher for AAA patients receiving EVAR regardless of rupture status; however, the cost is offset by lower odds of postoperative complications and in-hospital mortality. The observed decrease in ICER with age and EVAR use warrants further analysis. Our findings further validate the use of EVAR over OAR. These results provides supporting evidence for physicians and patients with AAA to inform shared decision making regarding endovascular or OAR options.