Gender Differences in Aortic Neck Morphology in Patients with Abdominal Aortic Aneurysms Undergoing Elective Endovascular Aneurysm Repair

Effect of vertebral compression fractures on aortic neck angulation after endovascular aneurysm repair

OBJECTIVE

Aortic neck angulation (ANA) prior to endovascular aneurysm repair (EVAR) and its changes after EVAR are considered important predictors of postoperative complications. We sought to assess the effects of vertebral body height loss on ANA in patients post-EVAR.

METHODS

All patients who had undergone EVAR for infrarenal aortic aneurysms in our institution between August 2010 and December 2018 were assessed. Anterior and posterior vertebral body heights were measured in all patients on preoperative, early postoperative, and follow-up computed tomography scans (T12-L5 vertebral bodies). Patients who had significant height loss in their follow-up period were designated as the Study group. These were matched to a Control group of the same size using propensity-score matching based on age, gender, and duration between follow-up scans. Aortic neck morphology indices including ANA and its changes were measured, and information related to postoperative endoleaks and aneurysm sac size were extracted in the Study and Control groups.

RESULTS

During the follow-up period, 10 of 185 patients had a radiologically significant vertebral body compression fracture. There was no significant difference between the Study (n = 10) and Control groups in age (77.6 ± 6.9 vs 77.2 ± 7.5 years; P = .64), gender (seven males and three females in each group; P = 1.0), duration between postoperative scans (1830 ± 665 vs 1800 ± 670 days; P = .25), preoperative ANA (36.0° ± 15.6° vs 42.4° ± 18.6°; P = .41), and early postoperative ANA (21.9° ± 11.7° vs 20.9° ± 16.3°; P = .72). Changes in ANA in the postoperative period (7.2° ± 11.1° vs -4.7° ± 6.7°; P = .009; power = .838) were significantly higher in the Study group.

CONCLUSION

Post-EVAR vertebral body compression fractures exacerbate ANA. Awareness of this can guide both preoperative assessment and postoperative management and follow-up.

Outcomes after EVAR in females are similar to males

INTRODUCTION

Women are less likely to develop infrarenal abdominal aortic aneurysm; however, when they do, it is almost always associated with challenging anatomy, more rapid aneurysmal growth rate and earlier rupture. Women generally have poorer outcomes following open aneurysm repair; and in this respect, the present study aims to evaluate if it is so after endovascular repair.

METHODS

A retrospective analysis of our database was performed for patients underwent endovascular aneurysm repair (EVAR) between January 2013-March 2020. 249 elective EVAR patients were evaluated. Patients were categorized according to gender and 26 patients (10.4%) were female. Demographics and pre-peri-postoperative findings were compared. Propensity score matching (ratio 1:1) was performed to reduce selection bias.

RESULTS

In the overall unmatched cohort, female population had more diabetes mellitus (p = 0.016) and hypertension (p = 0.005). However, coronary artery disease (p = 0.005) and coronary artery bypass grafting (p = 0.006) were more in male gender. Non-IFU implantation was higher in female group (38.5% vs. 11.5%, p = 0.025). After propensity matching, even though it was not statistically significant, early mortality for female gender was higher when compared to male gender (7.7% and 0%, respectively, p = 0.490). In the follow-up period, no difference in all-cause mortality, secondary interventions or complications have been observed between the genders.

CONCLUSION

Challenging anatomy and subsequently treated patients outside IFU may be the reasons for higher morbidity and mortality in women. However, despite these factors female and male patients revealed equivalent early and late results.

Suitability of the Aortic Neck Anatomy for Endovascular Aneurysm Repair in Korean Patients with Abdominal Aortic Aneurysm

Purpose

To evaluate the aortic neck anatomy in Korean patients with abdominal aortic aneurysms (AAAs).

Materials and Methods

We examined computed tomography scans of 343 patients with AAAs (≥5.5 cm for men or ≥5 cm for women) between 2009 and 2018. Eligibility of neck anatomy for endovascular aneurysm repair (EVAR) was assessed with the standard instructions for use (IFU) (length ≥15 mm, suprarenal angulation (SRA) ≤45°, infrarenal angulation (IRA) ≤60°, and diameter 18-32 mm) and the extended IFU (length ≥10 mm, SRA ≤60°, IRA ≤75°, and diameter 17-32 mm).

Results

There were 71 women (20.7%), and 61 patients (17.8%) with rupture. Women had smaller neck diameters (21.3 vs. 23.4 mm, P<0.001 for proximal neck; 22.2 vs. 24.5 mm, P<0.001 for distal neck), and higher angulations (51.5° vs. 37.8°, P<0.001 for SRA; 77.7° vs. 57.0°, P<0.001 for IRA) than men. However, the neck length was not significantly different. Patients with ruptured AAAs had shorter neck lengths (21.0 vs. 26.8 mm, P=0.005) than those with intact AAAs. However, the neck diameters and angulations were not significantly different. EVAR eligibility for standard and extended IFUs was found in 37.5% and 55.1% of men, and 11.3% and 25.4% of women (P<0.001 for both IFUs); neck anatomy was eligible in 34.0% of intact AAAs and 23.0% of ruptured AAAs (P=0.098).

Conclusion

A significant proportion of the Korean patients did not meet the IFU for EVAR, mainly due to the angulated neck. Women, and patients with ruptured AAAs, were less likely to meet the IFU criteria.

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.

Sex-dependent outcomes following elective endovascular aortic repair

BACKGROUND

Evidence has shown that women derive less benefit from endovascular aortic repair (EVAR) in large part due to more challenging aortoiliac anatomy. This study sought to examine whether sex-dependent outcomes exist following elective EVAR cases.

METHODS

An institutional retrospective review was performed on patients who underwent elective EVAR procedures between 2008 and 2014. Outcome data collected included procedural and hospital morbidity, mortality, and overall EVAR durability based on the incidence of unplanned graft-related secondary interventions (SIs) (e.g., open conversion, proximal or distal extensions, and coil embolizations).

RESULTS

One hundred eighty-one patients (150 men, 31 women) met the study inclusion criteria. Median follow-up was 40.3 mo. Women had more challenging anatomy compared to men including smaller overall iliac diameters (6.8 mm versus 8.0 mm, P < 0.001) and more severe iliac angulation (77% moderate to severe versus 44%, P < 0.001). Women had increased risk of postoperative complications compared to men (41.9% versus 11.3%, P = 0.003). There was no perioperative mortality in our series of elective EVAR cases. Median 5-y survival following EVAR was 64.4% for men and 76.3% for women (P = 0.599). Late SI rates following EVAR was 10.5% with 16 (10.7%) men and 3 (9.7%) women needing interventions (P = 0.870). Overall durability of EVAR extrapolated as time to SIs was 91% at 2 y and 85% at 5 y. Factors predisposing SIs were iliac tortuosity (P = 0.046), aortic neck angle (P = 0.022), and endoleak at the follow-up (P = 0.030).

CONCLUSIONS

In this study, immediate outcomes following EVAR were different between men and women, with women having increased rates of postoperative complications. Mortality and overall long-term durability of EVAR, however, were the same between sexes despite anatomical differences. EVAR durability was significantly dependent on the severity of iliac tortuosity, aortic neck angulation, and presence of endoleak at the follow-up.

Proximal Aortic Neck Progression: Before and After Abdominal Aortic Aneurysm Treatment

Several risk factors including short or highly angulated proximal aortic neck have been associated with long-term outcomes after endovascular or open abdominal aortic aneurysm (AAA) repair. However, research data have emerged recently concerning the behavior of proximal aortic neck, and several authors have tried to evaluate this behavior after endovascular or open repair. Additionally, computed tomography angiography (CTA) remains the golden standard for detecting and observing the morphology of an AAA, both before and after treatment. Moreover, the question of whether the proximal neck’s progression independently affects postoperative morbidity and reintervention risks still remains. Therefore, this focused review aims to present all relevant data on the behavior of an AAAs neck, based on CTA imaging before and after repair, in order to produce useful conclusions for future clinical practice.

Endovascular Abdominal Aneurysm Repair in Women: What are the Differences Between the Genders?

INTRODUCTION:

Abdominal aortic aneurysm has a lower incidence in the female population, but a higher complication rate. It was been hypothesized that some anatomical differences of abdominal aortic aneurysm in women could be responsible for that. We proposed to analyze our data to understand the differences in the clinical and anatomical characteristics and the outcomes of patients undergoing endovascular aneurysm repair, according to gender.

METHODS:

A retrospective analysis of patients undergoing endovascular aneurysm repair between 2001-2013 was performed. Patients were divided according gender and evaluated regarding age, atherosclerotic risk factors, aneurysm anatomic features, endograft type, anesthesic risk classification, length of stay, reinterventions and mortality. Two statistical studies were performed, first comparing women and men (Group A) and a second one comparing women and men, adjusted by age (Group B).

RESULTS:

Of the 171 patients, only 5.8% (n=10) were females. Women were older (P<0.05) and the number of women with no atherosclerotic risk factor was significantly higher. The comparison adjusted by age revealed women with statistically less smoking history, less cerebrovascular disease and ischemic heart disease. Women had a trend to more complex anatomy, with more iliac intern artery aneurysms, larger aneurysm diameter and neck angulations statistically more elevated. No other variables were statistically different between age groups, neither reintervention nor mortality rates.

CONCLUSION:

Our study showed a clear difference in the clinical characteristics of women. The female population was statistically older, and when compared with men adjusted by age, had less atherosclerotic risk factors and less target organ disease. Women showed a more complex anatomy but with the same outcomes.