The Society for Vascular Surgery practice guidelines on the care of patients with an abdominal aortic aneurysm

Causal association between Neuroticism and risk of aortic aneurysm: A bidirectional two-sample Mendelian randomization study

BACKGROUND

The objective of this study was to analyze the causal relationship between Neuroticism and aortic aneurysm using Mendelian randomization (MR). The study aimed to establish a foundation for the development of effective prevention and treatment strategies.

METHODS

Genetic association data for Neuroticism were obtained from the UK Biobank, which included 393,411 individuals and 11,968,760 single nucleotide polymorphisms (SNPs). Genetic association data for aortic aneurysm were obtained from a genome-wide association study (GWAS), which included 479,194 individuals and 24,191,825 SNPs. Heterogeneity was assessed using the Cochran's Q statistic test. The study also utilized the MR Pleiotropy RESidual Sum and Outlier (Mr-PRESSO) test, as well as the MR-Egger regression method, to examine horizontal pleiotropy and determine the reliability of the findings through the leave-one-out method.

RESULTS

Forward MR analysis showed that the risk of aortic aneurysm was elevated in individuals with genetically predicted Neuroticism compared to those without Neuroticism (OR = 1.1315, 95 % CI: 1.0269-1.2468; P = 0.0126). The Cochran's Q test showed no heterogeneity (P > 0.05), and the MR-PRESSO test did not identify instrumental variables of horizontal pleiotropy (P > 0.05). The MR analysis remained robust after removing SNPs one by one. Inverse MR analysis did not observe an association between aortic aneurysm and having Neuroticism OR = 1.030, 95 % CI: 0.9459-1.118, P = 0.488).

CONCLUSION

Our study has established a clear causal relationship between genetically determined Neuroticism and the development of aortic aneurysms. It is therefore important to intensify screening and prevention efforts for aortic aneurysms in neurotic patients. It also opens new avenues for exploring the disease's pathogenesis.

Artificial intelligence-driven multiomics predictive model for abdominal aortic aneurysm subtypes to identify heterogeneous immune cell infiltration and predict disease progression

BACKGROUND

Abdominal aortic aneurysm (AAA) poses a significant health risk and is influenced by various compositional features. This study aimed to develop an artificial intelligence-driven multiomics predictive model for AAA subtypes to identify heterogeneous immune cell infiltration and predict disease progression. Additionally, we investigated neutrophil heterogeneity in patients with different AAA subtypes to elucidate the relationship between the immune microenvironment and AAA pathogenesis.

METHODS

This study enrolled 517 patients with AAA, who were clustered using k-means algorithm to identify AAA subtypes and stratify the risk. We utilized residual convolutional neural network 200 to annotate and extract contrast-enhanced computed tomography angiography images of AAA. A precise predictive model for AAA subtypes was established using clinical, imaging, and immunological data. We performed a comparative analysis of neutrophil levels in the different subgroups and immune cell infiltration analysis to explore the associations between neutrophil levels and AAA. Quantitative polymerase chain reaction, Western blotting, and enzyme-linked immunosorbent assay were performed to elucidate the interplay between CXCL1, neutrophil activation, and the nuclear factor (NF)-κB pathway in AAA pathogenesis. Furthermore, the effect of CXCL1 silencing with small interfering RNA was investigated.

RESULTS

Two distinct AAA subtypes were identified, one clinically more severe and more likely to require surgical intervention. The CNN effectively detected AAA-associated lesion regions on computed tomography angiography, and the predictive model demonstrated excellent ability to discriminate between patients with the two identified AAA subtypes (area under the curve, 0.927). Neutrophil activation, AAA pathology, CXCL1 expression, and the NF-κB pathway were significantly correlated. CXCL1, NF-κB, IL-1β, and IL-8 were upregulated in AAA. CXCL1 silencing downregulated NF-κB, interleukin-1β, and interleukin-8.

CONCLUSION

The predictive model for AAA subtypes demonstrated accurate and reliable risk stratification and clinical management. CXCL1 overexpression activated neutrophils through the NF-κB pathway, contributing to AAA development. This pathway may, therefore, be a therapeutic target in AAA.

Preoperative risk factors for 1-year mortality in patients undergoing fenestrated endovascular aortic aneurysm repair in the US Aortic Research Consortium

BACKGROUND

Early survival (1-year) after elective repair of complex abdominal aortic aneurysms (AAA) or thoracoabdominal aortic aneurysms (TAAA) can be used as an indicator of successful repair and provides a reasonable countermeasure to the annual rupture risk based on diameter. We aimed to identify preoperative factors associated with 1-year mortality after fenestrated or branched endovascular aortic repair (F/BEVAR) and develop a predictive model for 1-year mortality based on patient-specific risk profiles.

METHODS

The US-Aortic Research Consortium database was queried for all patients undergoing elective F/BEVAR for complex AAA (cAAA) or TAAA from 2005 to 2022. The primary outcome was 1-year survival based on preoperative risk profile. Multivariable Cox regression was used to determine preoperative variables associated with 1-year mortality overall and by extent of aortic pathology. Logistic regression was performed to build a predictive model for 1-year mortality based on number of risk factors present.

RESULTS

A total of 2099 patients met the inclusion criteria for this study (cAAA: n = 709 [34.3%]; type 1-3 TAAA: n = 777 [37.6%]; type 4-5 TAAA: n = 580 [28.1%]). Multivariable Cox regression identified the following significant risk factors associated with 1-year mortality: current smoker, chronic obstructive pulmonary disease, congestive heart failure (CHF), aortic diameter >7 cm, age >75 years, extent 1-3, creatinine >1.7 mg/dL, and hematocrit <36%. When stratified by extent of aortic involvement, multivariable Cox regression revealed risk factors for 1-year mortality in cAAA (CHF maximum aortic diameter >7 cm, hematocrit <36 mg/dL, and current smoking status), type 1-3 TAAA (chronic obstructive pulmonary disease, CHF, and age >75 years), and type 4-5 TAAA (age >75 years, creatinine >1.7 mg/dL, and hematocrit <36 mg/dL). Logistic regression was then used to develop a predictive model for 1-year mortality based on patient risk profile. Appraisal of the model revealed an area under the curve of 0.64 (P < .001), and an observed to expected ratio of 0.85.

CONCLUSIONS

This study describes multiple risk factors associated with an increase in 1-year mortality after F/BEVAR. Given that elective repair of cAAA or TAAA is offered to some patients in whom future rupture risk outweighs operative risk, these findings suggest that highly comorbid patients with smaller aneurysms may not benefit from repair. Descriptive and predictive models for 1-year mortality based on patient risk profiles can serve as an adjunct in clinical decision-making when considering elective F/BEVAR.

The sac evolution imaging follow-up after endovascular aortic repair: An international expert opinion-based Delphi consensus study

OBJECTIVE

Management of follow-up protocols after endovascular aortic repair (EVAR) varies significantly between centers and is not standardized according to sac regression. By designing an international expert-based Delphi consensus, the study aimed to create recommendations on follow-up after EVAR according to sac evolution.

METHODS

Eight facilitators created appropriate statements regarding the study topic that were voted, using a 4-point Likert scale, by a selected panel of international experts using a three-round modified Delphi consensus process. Based on the experts' responses, only those statements reaching a grade A (full agreement ≥75%) or B (overall agreement ≥80% and full disagreement <5%) were included in the final document.

RESULTS

One-hundred and seventy-four participants were included in the final analysis, and each voted the initial 29 statements related to the definition of sac regression (Q1-Q9), EVAR follow-up (Q10-Q14), and the assessment and role of sac regression during follow-up (Q15-Q29). At the end of the process, 2 statements (6.9%) were rejected, 9 statements (31%) received a grade B consensus strength, and 18 (62.1%) reached a grade A consensus strength. Of 27 final statements, 15 (55.6%) were classified as grade I, whereas 12 (44.4%) were classified as grade II. Experts agreed that sac regression should be considered an important indicator of EVAR success and always be assessed during follow-up after EVAR.

CONCLUSIONS

Based on the elevated strength and high consistency of this international expert-based Delphi consensus, most of the statements might guide the current clinical management of follow-up after EVAR according to the sac regression. Future studies are needed to clarify debated issues.

The Role of Narrow Aortic Bifurcation in Affecting EVAR Treatment and Outcomes

BACKGROUND

The narrow aortic bifurcation (NAB) is considered a risk factor for endograft thrombosis after aorto-biiliac endovascular aneurysm repair (EVAR) for aortic or iliac aneurysm. Nowadays, no consensus on the threshold diameter for the definition of NAB is reached and other aortic bifurcation features are rarely considered. The aim of the study is to assess the EVAR outcomes using bifurcated endograft according to anatomical characteristics of aortic bifurcation.

METHODS

The study included patients treated with primary EVAR from 2016 to 2022. A retrospective analysis of single-center prospectively collected database was performed. Patients were classified in standard aortic bifurcation (SAB) (aortic bifurcation diameter >20 mm), NAB (≤20 mm and >16 mm), and extremely NAB (eNAB) (≤16 mm). The 3 groups were compared in terms of patient demographics, risk factors, procedure setting (elective or urgent/emergent), and type of deployed endograft. In NAB and eNAB groups, severe calcification (SC) and length of stenotic aortic bifurcation >10 mm (long-NAB) were assessed from preoperative imaging. In SAB, NAB, and eNAB groups, following outcomes were evaluated: rate of intraoperative iliac endograft stenting (unilateral or kissing stenting), primary patency (PP), freedom from endograft-related reintervention, and overall survival during follow-up.

RESULTS

The total number of deployed aorto-biiliac endografts was 365 (mean age: 76.6 ± 7.4 years; male 89.3%): SAB 298 (81.6%), NAB 57 (15.6%), and eNAB 10 (2.7%) cases. Female gender, chronic obstructive pulmonary disease patients, and active smokers were more frequent in patients with smaller aortic bifurcation diameter (P = 0.002, 0.039, and 0.010, respectively). In NAB and eNAB groups, SC was reported in 18/67 cases (26.9%) and long-NAB in 15/67 cases (25.4%). Patients with eNAB have more frequent SC of aortic bifurcation (60% vs. NAB 21.1%, P = 0.018) and long-NAB (50% vs. NAB 17.5%, P = 0.023). In SAB, NAB, and eNAB, intraoperative iliac endograft stenting was performed in 34/298 (11.4%), 9/57 (15.8%), and 5/10 (50%), respectively (P = 0.001). Kissing stenting was performed more frequently in groups with smaller aortic bifurcation diameter (P = 0.010). Mean follow-up was 30.2 ± 21.5 months. At 1, 3, and 5 years, PP was 98.5%, 96.6%, and 95.6%, respectively. eNAB had lower rate of PP compared to NAB group (P = 0.030). Long-NAB had lower rate of PP (P = 0.035). At 1, 3, and 5 years, endograft-related reintervention was 96.8%, 86.7%, and 76.7%, respectively, with no differences between 3 groups (P = 0.423). At 1, 3, and 5 years, survival was 92.5%, 77.6%, and 58.1%, respectively, with no difference between SAB, NAB, and eNAB (P = 0.673).

CONCLUSIONS

Female gender, chronic obstructive pulmonary disease patients, and active smokers have more frequently smaller aortic bifurcation diameter. eNAB patients have more challenging anatomical characteristics compared with NAB group, requiring higher rate of intraoperative stenting, especially kissing stenting. Mid-term PP seems to be negatively influenced by aortic bifurcation ≤16 mm and long-NAB.

Implications and late outcomes of type II endoleaks after endovascular aneurysm repair

OBJECTIVE

Type II endoleaks (T2ELs) are the most common cause of reintervention after endovascular aneurysm repair (EVAR). Although most resolve spontaneously, the long-term implications of T2ELs remain elusive. We aim to evaluate the impact of persistent and late T2ELs on clinical outcomes after EVAR.

METHODS

This was a single-institution retrospective review of patients who underwent EVAR for degenerative infrarenal abdominal aortic aneurysm between January 2010 and June 2022 with no type I (T1EL) or III (T3EL) endoleak seen at EVAR completion. Patients were categorized based on T2EL status. Group 1 included patients with never detected or transient T2ELs (detected at EVAR completion but not after). Group 2 encompassed persistent T2ELs (seen at EVAR completion and again during follow-up) and late T2ELs (detected for the first time at any point during follow-up). Time-to-event analysis was conducted using a time-dependent approach to T2EL status. Primary outcomes included freedom from sac enlargement (SE), aneurysm-related reinterventions, and overall survival.

RESULTS

A total of 803 patients met inclusion criteria. Group 1 included 418 patients (52%), of which 85% had no T2ELs and 15% had transient T2ELs. Group 2 had 385 patients; 23% had persistent T2ELs, and 77% developed a new T2EL. Patients in group 1 had a higher prevalence of smoking (88% vs 83%; P < .001), chronic obstructive pulmonary disease (33% vs 25%; P = .008), chronic kidney disease (13% vs 8%; P = .021), and a higher mean Society for Vascular Surgery score (7 vs 6 points; P = .049). No differences were found in aneurysm diameter or morphology. Mean follow-up was 5 years for the entire cohort. In Group 2, 58 patients (15%) underwent T2EL treatment, most commonly transarterial embolization. At 10 years after EVAR, Group 2 was associated with lower freedom from SE (P < .001) and abdominal aortic aneurysm-related reinterventions (P < .001) and comparable overall survival (P = .42). More T1ELs were detected during follow-up in Group 2 (6 [1%] vs 20 [5%]; P = .004), with 15 (75%) of these detected at a median of 3 years after the T2EL. No difference between groups was observed in explant (0.7% vs 2.1%; P = .130) or aneurysm rupture (0.5% vs 1.3%; P = .269) rates.

CONCLUSIONS

One-half of patients treated with infrarenal EVAR developed persistent/late T2ELs, which are associated with a higher risk of SE and reinterventions. No difference in overall survival or aneurysm rupture risk was seen at 10 years, based on T2EL status or T2EL intervention. A conservative approach to T2ELs may be appropriate for most patients with absent T1ELs or T3ELs.

Variability in short-term mortality following repair of ruptured abdominal aortic aneurysms across centers and physicians

BACKGROUND

Variation in the care management of repairs for ruptured infrarenal abdominal aortic aneurysms between centers and physicians, such as procedural volumes, may explain differences in mortality outcomes. First, we quantified the center and physician variability associated with 30- and 90-day mortality risk after ruptured open surgical repair (rOSR) and ruptured endovascular aneurysm repair (rEVAR). Second, we explored wheter part of this variability was attributable to procedural volume at the center and physician levels.

METHODS

Two cohorts including rOSR and rEVAR procedures between 2013 and 2019 were analyzed from the Vascular Quality Initiative database. Thirty- and 90-day all-cause mortality rates were derived from linked Medicare claims data. The median odds ratio (MOR) (median mortality risk from low- to high-risk cluster) and intraclass correlation coefficient (ICC) (variability attributable to each cluster) for 30- and 90-day mortality risks associated with center and physician variability were derived using patient-level adjusted multilevel logistic regression models. Procedural volume was calculated at the center and physician levels and stratified by quartiles. The models were sequentially adjusted for volumes, and the difference in ICCs (without vs with accounting for volume) was calculated to describe the center and physician variability in mortality risk attributable to volumes.

RESULTS

We included 450 rOSRs (mean age, 74.5 ± 7.6 years; 23.5% female) and 752 rEVARs (76.4 ± 8.4 years; 26.1% female). After rOSRs, the 30- and 90-day mortality rates were 32.9% and 38.7%, respectively. No variability across centers and physicians was noted (30- and 90-day MORs ≈1 and ICCs ≈0%). Neither center nor physician volume was associated with 30-day (P = .477 and P = .796) or 90-day mortality (P = .098 and P = .559). After rEVAR, the 30- and 90-day mortality rates were 21.3% and 25.5%, respectively. Significant center variability (30-day MOR, 1.82 [95% confidence interval (CI), 1.33-2.22]; ICC, 11% [95% CI, 2%-36%]; and 90-day MOR, 1.76 [95% CI, 1.37-2.09]; ICC, 10% [95% CI, 3%-30%]), but negligeable variability across physicians (30- and 90-day MORs ≈1 and ICCs ≈0%) were noted. Neither center nor physician volume were associated with 30-day (P = .076 and P = .336) or 90-day mortality risk (P = .066 and P = .584). The center variability attributable to procedural volumes was negligeable (difference in ICCs, 1% for 30-day mortality; 0% for 90-day mortality).

CONCLUSIONS

Variability in practice from center to center was associated with short-term mortality outcomes in rEVAR, but not for rOSR. Physician variability was not associated with short-term mortality for rOSR or rEVAR. Annualized center and physician volumes did not significantly explain these associations. Further work is needed to identify center-level factors affecting the quality of care and outcomes for ruptured abdominal aortic aneurysms.

Postdissection aortic aneurysm sac enlargement after fenestrated and branched endovascular aortic aneurysm repair

OBJECTIVES

Aneurysm sac changes after fenestrated-branched endovascular aneurysm repair (FBEVAR) for postdissection thoracoabdominal aortic aneurysms (PD-TAAs) are poorly understood. Partial thrombosis of the false lumen and endoleaks may impair sac regression. To characterize sac changes after FBEVAR for PD-TAAs, this study examined midterm results and predictors for sac enlargement.

METHODS

FBEVARs performed for PD-TAAs in 10 physician-sponsored investigational device exemption studies from 2008 to 2023 were analyzed. The maximum aortic aneurysm diameter was compared between the 30-day computed tomography angiogram and follow-up imaging studies. Aneurysm sac enlargement was defined as an increase in diameter of ≥5 mm. Kaplan-Meier curves and Cox regression were used to evaluate sac enlargement and midterm FBEVAR outcomes.

RESULTS

Among 3296 FBEVARs, 290 patients (72.4% male; median age, 68.4 years) were treated for PD-TAAs. Most aneurysms treated were extent II (72%) and III (12%). Mean aneurysm diameter was 66.5 ± 11.2 mm. Mortality at 30 days was 1.4%. At a mean follow-up of 2.9 ± 1.9 years, at least one follow-up imaging study revealed sac enlargement in 43 patients (15%), sac regression in 115 patients (40%), and neither enlargement nor regression in 137 (47%); 5 (2%) demonstrated both expansion and regression during follow-up. Freedom from aneurysm sac enlargement was 93%, 82%, and 80% at 1, 3, and 5 years, respectively. Overall, endoleaks were detected in 27 patients (63%) with sac enlargement and 143 patients (58%) without enlargement (P = .54). Sac enlargement was significantly more frequent among older patients (mean age at the index procedure, 70.2 ± 8.9 years vs 66.5 ± 11 years; P = .04) and those with type II endoleaks at 1 year (74% vs 52%; P = .031). Cox regression revealed age >70 years at baseline (hazard ratio [HR], 2.146; 95% confidence interval [CI], 1.167-3.944; P = .010) and presence of type II endoleak at 1 year (HR, 2.25; 95% CI, 1.07-4.79; P = .032) were independent predictors of sac enlargement. Patient survival was 92%, 81%, and 68% at 1, 3, and 5 years, respectively. Cumulative target vessel instability was 7%, and aneurysm-related mortality was 2% at 5 years. At least 42% of patients required secondary interventions. Sac enlargement did not affect patient survival.

CONCLUSIONS

Aneurysm sac enlargement occurs in 15% of patients after FBEVAR for PD-TAAs. Elderly patients (>70 years at baseline) and those with type II endoleaks at 1 year may need closer monitoring and secondary interventions to prevent sac enlargement. Despite sac enlargement in some patients, aneurysm-related mortality at 5 years remains low and overall survival was not associated with sac enlargement.

Effect of Chronic Kidney Disease on 30-Day Outcomes in Endovascular Repair of Complex Abdominal Aortic Aneurysm

BACKGROUND

Chronic kidney disease (CKD) has been identified as an independent predictor of poorer long-term prognosis after endovascular aneurysm repair (EVAR) for complex abdominal aortic aneurysm (AAA). However, its impact on short-term perioperative outcomes is conflicting, which can be important for preoperative risk stratification. This study aimed to evaluate the 30-day outcomes of patients with CKD following non-ruptured complex EVAR in a national registry.

METHODS

Patients who had EVAR for complex AAA were identified in ACS-NSQIP targeted database from 2012-2022. Complex AAA included juxtarenal, suprarenal, or pararenal proximal extent, Type IV thoracoabdominal aneurysm, and/or aneurysms treated with Zenith Fenestrated endograft. Exclusion criteria included age<18 years, ruptured AAA, acute intraoperative conversion to open, emergency presentation, and dialysis. Multivariable logistic regression was used to compare 30-day postoperative outcomes of CKD and non-CKD patients, where demographics, baseline characteristics, aneurysm diameter, distant aneurysm extent, anesthesia, and concomitant procedures were adjusted.

RESULTS

There were 695 (39.33%) and 1072 (60.67%) patients with and without CKD, respectively, who underwent EVAR for complex AAA. Patients with and without CKD have comparable 30-day mortality (aOR = 1.165, 95 CI = 0.646-2.099, P = 0.61). However, CKD patients had a higher risk of renal complications (aOR = 2.647, 95 CI = 1.399-5.009, P < 0.01) including higher progressive renal insufficiency (aOR = 3.707, 95 CI = 1.329-10.338, P = 0.01) and acute renal failure requiring renal replacement therapy (aOR = 2.533, 95 CI = 1.139-5.633, P = 0.02). All other 30-day outcomes were comparable between CKD and non-CKD patients.

CONCLUSION

Patients with CKD had similar 30-day mortality and morbidity rates but a higher risk of postoperative renal complications. Therefore, meticulous preoperative planning and postoperative management, which may include optimal hydration, appropriate contrast use, and close renal function monitoring, are essential for patients with CKD after complex EVAR.

An International, Expert-based, Delphi Consensus Document on Controversial Issues in the Management of Abdominal Aortic Aneurysms

OBJECTIVE

As a result of conflicting, inadequate or controversial data in the literature, several issues concerning the management of patients with abdominal aortic aneurysms (AAAs) remain unanswered. The aim of this international, expert-based Delphi Consensus document was to provide some guidance for clinicians on these controversial topics.

METHODS

A 3-Round Delphi Consensus document was produced with 44 experts on 6 pre-specified topics regarding the management of AAAs. All answers were provided anonymously. The response rate for each round was 100%.

RESULTS

Most participants (42 of 44; 95.4%) agreed that a minimum case volume/year is essential (or probably essential) for a center to offer open/endovascular AAA repair (EVAR). Furthermore, 33 of 44 (75.0%) believed that AAA screening programs are (probably) still clinically effective and cost-effective. Additionally, most panelists (36 of 44; 81.9%) voted that surveillance after EVAR should be (or should probably be) lifelong. Finally, 35 of 44 (79.7%) participants thought that women smokers should (or should probably/possibly) be considered for screening at 65 years of age similar to men. No consensus was achieved regarding lowering the threshold for AAA repair and the need for deep venous thrombosis prophylaxis in patients undergoing EVAR.

CONCLUSIONS

This expert-based Delphi Consensus document provides guidance for clinicians regarding specific unresolved issues. Consensus could not be achieved in some topics, highlighting the need for further research in those areas.

The Gore Viabahn balloon-expandable stent graft as bridging stent in complex endovascular aortic procedures at 3-years performs better in fenestrations

OBJECTIVE

Complex endovascular procedures are now recognized as the gold standard treatments for extensive aortic diseases. Bridging stents (covered stents used to couple the aortic graft to the visceral vessels) play a pivotal role, yet there is currently no dedicated device available on the market. The aim of the study was to evaluate the mid-term performance of the Gore Viabahn balloon-expandable (VBX) stent graft as a bridging stent for target visceral vessels (TVV).

METHODS

Data from all consecutive patients undergoing fenestrated and branched endovascular aortic repair (F/BEVAR) and receiving the VBX stent graft as a bridging stent between July 2018 and September 2022 were prospectively collected and subsequently analyzed retrospectively. Primary endpoints included freedom from TVV instability and freedom from TVV-related reinterventions, both overall and in comparison between branched and fenestrated graft configurations. Secondary endpoints were overall survival, procedure and TVV-related (in an intent-to-treat basis) technical success, freedom from type IC/IIIC endoleak, and freedom from TVV patency loss.

RESULTS

Sixty-three patients were treated with a F/BEVAR using VBX as bridging stent, of those 47 (74.6%) presented an atherosclerotic aneurysm, 7 (11.1%) a post-dissecative aneurysm and 9 (14.3%) an anastomotic pseudoaneursym or a type IA endoleak in a previous EVAR. Included in the aortic repair were 231 out of 243 (95.1%) total visceral vessels. The intra-operative requirement of 13 additional VBX determined a TVV-related technical success of 94.4%. Mean follow-up was 26.1 ± 16.4 months. Estimated overall survival at 36-months was 73 ± 7.5%. Estimated rates at 36-months for freedom from type IC/IIIC endoleaks and TVV primary patency were 90.6 ± 3.9% and 99 ± 0.7%, respectively. Estimated rate at 36-months for freedom from TVV-instability was 92.1 ± 3% and did not differ between branched and fenestrated configurations, while freedom from TVV-related reinterventions was 90.6 ± 3.1% and significantly in favor of fenestrations (69.4% versus 96.8%, p< .001). Multivariate analyses confirmed fenestrated configuration as a protective factor against TVV-related reinterventions (HR: .079; 95% CI: .016 - .403).

CONCLUSION

The VBX stent graft proves to be a reliable bridging stent for complex aortic procedures involving both fenestrated and branched endografts. While immediate results are deemed satisfactory, they favor fenestrations regarding need of reinterventions through 3-years. The success of the procedure heavily relies on a thorough understanding of the unique characteristics of this stent.

Tea polyphenol nanoparticles enable targeted siRNA delivery and multi-bioactive therapy for abdominal aortic aneurysms

Abdominal aortic aneurysm (AAA) is a life-threatening vascular disease, while there is a lack of pharmaceutical interventions to halt AAA progression presently. To address the multifaceted pathology of AAA, this work develops a novel multifunctional gene delivery system to simultaneously deliver two siRNAs targeting MMP-2 and MMP-9. The system (TPNs-siRNA), formed through the oxidative polymerization and self-assembly of epigallocatechin gallate (EGCG), efficiently encapsulates siRNAs during self-assembly. TPNs-siRNA safeguards siRNAs from biological degradation, facilitates intracellular siRNA transfection, promotes lysosomal escape, and releases siRNAs to silence MMP-2 and MMP-9. Additionally, TPNs, serving as a multi-bioactive material, mitigates oxidative stress and inflammation, fosters M1-to-M2 repolarization of macrophages, and inhibits cell calcification and apoptosis. In experiments with AAA mice, TPNs-siRNA accumulated and persisted in aneurysmal tissue after intravenous delivery, demonstrating that TPNs-siRNA can be significantly distributed in macrophages and VSMCs relevant to AAA pathogenesis. Leveraging the carrier's intrinsic multi-bioactive properties, the targeted siRNA delivery by TPNs exhibits a synergistic effect for enhanced AAA therapy. Furthermore, TPNs-siRNA is gradually metabolized and excreted from the body, resulting in excellent biocompatibility. Consequently, TPNs emerges as a promising multi-bioactive nanotherapy and a targeted delivery nanocarrier for effective AAA therapy.

Preemptive treatment of type II endoleak for abdominal aortic aneurysm with renal fusion (horseshoe kidney)

OBJECTIVE

To assess viability and safety of preemptive treatment of type II endoleak for abdominal aortic aneurysm (AAA) repairs.

METHODS

A 69-year-old man with renal fusion (horseshoe kidney) was referred for treatment of a 5.5 cm AAA. His anatomy was suitable for endovascular repair. The risk for type II endoleak was increased because of multiple infrarenal arterial orifices originating within the aneurysm sac. These included an accessory renal artery that supplied the renal isthmus, a patent inferior mesenteric artery, and a pair of large lumbar arteries originating from a single orifice (8 mm) at L3 spinal level. The lumbar orifice was selectively cannulated and occluded with thrombogenic coils 1 week prior to his endovascular aneurysm repair.

RESULTS

Aneurysm repair was uneventful with no signs of early or delayed endoleak and long-term follow-up of 5 years.

CONCLUSIONS

Preemptive coil embolization of perianeurysmal arteries may be considered as a safe and effective strategy for management of potential type II endoleak.

Beta Blockers are Associated with Increased Mortality without a Decrease in Reinterventions after Endovascular Abdominal Aortic Repair (EVAR)

OBJECTIVE

Predictors of sac behavior after EVAR and the impact of sac behavior on long-term survival are not well known. There are limited multicenter trials studying the impact of beta-blockers (BB) on sac behavior. Beta-blockers have consistently failed to show a benefit on AAA sac regression in patients with connective tissue disorders and the general population. This study aims to assess the association between BBs and sac behavior after endovascular aortic aneurysm repair (EVAR).

METHODS

Patients undergoing EVAR registered in Vascular Quality Initiative (VQI) (2003-2021) stratified by BB and no BB on discharged after an index procedure were assessed at follow-up of 30-days and 1-year. The primary outcomes included mortality and reintervention at 30-days and 1-year. The causes of reintervention were also studied at the defined time endpoints. Categorical and continuous variables were analyzed separately for association between the two groups. A p-value of <0.05 was considered statistically significant.

RESULTS

A total of 50,411 patients, stratified by BB (28,866; 57.3%), and No BB (21,545; 42.7%) were studied. Patients with hypertension, diabetes, COPD, coronary artery disease, prior history of coronary artery bypass graft or percutaneous coronary intervention, prior angioplasty or stent, lower extremity bypass, carotid surgery, major amputation, and smokers were more likely to be on a BB at the time of discharge (p<0.05). There was no significant difference in reinterventions when comparing patients with and without BB (p=0.061). At 30-day follow up, there was no significant difference between the two groups for any cause of reintervention. At 1-year follow up, patients on BB were less likely to need reintervention for graft occlusion (no BB 18.70%, BB 11.77%, p=0.002). There was no significant difference in reintervention for all other causes at 1-year follow up. There was an increase in 30-day (no BB 0.20%, BB 0.33%, p=0.007) and 1-year mortality (no BB 2.35%, BB 3.19%, p<0.001) in patients on beta-blockers. A time to event adjusted analysis based on Cox proportional hazard model revealed a 26% higher risk of 1-year mortality for patients on BB (HR:1.26 [1.10-1.41] p<0.001) CONCLUSION: Despite theoretical benefits of beta-blockers on aneurysm behavior, review of the largest national vascular surgery database shows that patients on beta-blockers do not have lower incidence of endovascular reinterventions after EVAR while additionally showing a higher mortality in this patient population.

Editor's Choice - Outcomes Following Intact and Ruptured Aneurysm Repair across Nations: Analysis of International Registry Data from the VASCUNET Collaboration 2014 - 2019

OBJECTIVE

To determine the peri-operative mortality rate for intact and ruptured abdominal aortic aneurysm (AAA) repair in 10 countries and to compare practice and outcomes over a six year period by age, sex, and geographic location.

METHODS

This VASCUNET study used prospectively collected data from vascular registries in 10 countries on primary repair of intact and ruptured AAAs undertaken between January 2014 and December 2019. The primary outcome was peri-operative death (30 day or in hospital). Logistic regression models were used to estimate the association between peri-operative death, patient characteristics, and type of procedure. Factors associated with the use of endovascular aortic aneurysm repair (EVAR) were also evaluated.

RESULTS

The analysis included 50 642 intact and 9 453 ruptured AAA repairs. The proportion of EVARs for intact repairs increased from 63.4% in 2014 to 67.3% in 2016 before falling to 62.3% in 2019 (p < .001), but practice varied between countries. EVAR procedures were more common among older patients (p < .001) and men (p < .001). Overall peri-operative mortality after intact AAA repair was 1.4% (95% confidence interval [CI] 1.3 - 1.5%) and did not change over time. Mortality rates were stable within countries. Among ruptured AAA repairs, the proportion of EVARs increased from 23.7% in 2014 to 35.2% in 2019 (p < .001). The average aortic diameter was 7.8 cm for men and 7.0 cm for women (p < .001). The overall peri-operative mortality rate was 31.3% (95% CI 30.4 - 32.2%); the rates were 36.0% (95% CI 34.9 - 37.2%) for open repair and 19.7% (95% CI 18.2 - 21.3%) for EVAR. This difference and shift to EVAR reduced peri-operative mortality from 32.6% (in 2014) to 28.7% (in 2019).

CONCLUSION

The international practice of intact AAA repair was associated with low mortality rates in registry reported data. There remains variation in the use of EVAR for intact AAAs across countries. Overall peri-operative mortality remains high after ruptured AAA, but an increased use of EVAR has reduced rates over time.

Center-level outcomes following elective fenestrated endovascular aortic aneurysm repair in the Vascular Quality Initiative database

OBJECTIVE

Hospital volume is associated with mortality after open aortic aneurysm repair. Fenestrated and branched endovascular aortic repair (B-FEVAR) has been increasingly used for repair of complex thoracoabdominal and juxtarenal aneurysms, but evidence of a center-volume relationship is limited. We aimed to measure the association of center volume with in-hospital mortality, postoperative outcomes, and 1-year survival following B-FEVAR.

METHODS

Patients undergoing elective endovascular thoracoabdominal and complex abdominal aneurysm repair with branch intervention (2014-2021) listed within the national Vascular Quality Initiative Thoracic Endovascular Aortic Repair/Complex EVAR database were analyzed. Centers were grouped into quartiles by mean annual procedure volume. Multivariable regression was used to evaluate the effect of center volume on in-hospital mortality adjusting for baseline and procedural characteristics. Kaplan-Meier estimation, log rank test, and mixed effects Cox regression were used to evaluate 1-year survival.

RESULTS

A total of 4302 adult elective F-BEVAR procedures were identified at a total of 163 centers. In-hospital mortality did not differ by hospital volume (quartile [Q]1 = 35/1059 [3.3%]; Q2 = 30/1063 [2.8%]; Q3 = 33/1120 [2.9%]; and Q4 = 44/1060 [4.2%]; P = .308). The high volume group had a higher rate of major complication (Q1 = 14.9%; Q2 = 12.8%; Q3 = 13.3%; and Q4 = 20.1%; adjusted P < .001). Physician-modified grafts were more frequently employed in high-volume centers (Q1 = 4.5%; Q2 = 18.7%; Q3 = 11.3%; and Q4 = 19.2%; P < .001), with a decreased incidence of any endoleak noted at the end of the procedure (Q1 = 34.9%; Q2 = 32.8%; Q3 = 30.0%; and Q4 = 29.0%; P = .003). In the multivariable analysis, in-hospital mortality was not associated with center volume, comparing very low volume to medium- and high-volume centers (odds ratio [95% confidence interval] vs Q4: Q1 = 1.1 [0.6-1.9], Q2 = 0.6 [0.4-1.1], and Q3 = 0.9 [0.5-1.5]; all P > .05). No significant difference was found in 1-year survival between center volume groups.

CONCLUSIONS

In-hospital mortality is not associated with procedure volume within centers performing complex endovascular aortic repair. However, complication rates and endoleak may be associated with procedure volume. Long-term outcomes by annualized procedure volume, specifically graft durability and sac expansion, should be investigated.

The Role of Integrated Air Transport System in Managing Patients with Abdominal Aortic Aneurysm Rupture

OBJECTIVE

Ruptured abdominal aortic aneurysms (rAAAs) are highly morbid emergencies. Not all hospitals are equipped to repair them, and an air ambulance network may aid in regionalising specialty care to quaternary referral centres. The association between travel distance by air ambulance and rAAA mortality in patients transferred as an emergency for repair was examined.

METHODS

A retrospective review of institutional data. Adults with rAAA (2002 - 2019) transferred from an outside hospital (OSH) to a single quaternary referral centre for repair via air ambulance were identified. Patients who arrived via ground transport or post-repair at an OSH for continued critical care were excluded. Patients were divided into near and far groups based on the 75th percentile of the straight line travel distance (> 72 miles) between hospitals. The primary outcome was 30 day mortality. Multivariable logistic regression was used to assess the association between distance and mortality after adjusting for age, sex, ethnicity, cardiovascular comorbidities, and repair type.

RESULTS

A total of 290 patients with rAAA were transported a median distance of 40.4 miles (interquartile range 25.5, 72.7) with 215 (74.1%) near and 75 (25.9%) far patients. Both the near and far groups had similar ages, sex, and ethnicity. There was no difference in pre-operative loss of consciousness, intubation, or cardiac arrest between groups. Endovascular aneurysm repair utilisation and intra-operative aortic occlusion balloon use were also similar. Neither the observed (26.8% vs. 23.9%, p = .61) nor the adjusted odds ratio (0.70, 95% confidence interval 0.36 - 1.39, p = .32) 30 day mortality rate differed significantly between the near and far groups.

CONCLUSION

Increasing distance travelled during transfer by air ambulance was not associated with worse outcomes in patients with rAAA. The findings support the regionalisation of rAAA repair to large quaternary centres via an integrated and robust air ambulance network.

A Dual-Targeting, Multi-Faceted Biocompatible Nanodrug Optimizes the Microenvironment to Ameliorate Abdominal Aortic Aneurysm

Abdominal aortic aneurysm (AAA) is a highly lethal cardiovascular disease that currently lacks effective pharmacological treatment given the complex pathophysiology of the disease. Here, single-cell RNA-sequencing data from patients with AAA and a mouse model are analyzed, which reveals pivotal pathological changes, including the M1-like polarization of macrophages and the loss of contractile function in smooth muscle cells (SMCs). Both cell types express the integrin αvβ3, allowing for their dual targeting with a single rationally designed molecule. To this end, a biocompatible nanodrug, which is termed EVMS@R-HNC, that consists of the multifunctional drug everolimus (EVMS) encapsulated by the hepatitis B virus core protein modifies to contain the RGD sequence to specifically bind to integrin αvβ3 is designed. Both in vitro and in vivo results show that EVMS@R-HNC can target macrophages as well as SMCs. Upon binding of the nanodrug, the EVMS is released intracellularly where it exhibits multiple functions, including inhibiting M1 macrophage polarization, thereby suppressing the self-propagating inflammatory cascade and immune microenvironment imbalance, while preserving the normal contractile function of SMCs. Collectively, these results suggest that EVMS@R-HNC presents a highly promising therapeutic approach for the management of AAA.

Sex Influence on Fenestrated and Branched Endovascular Aortic Aneurysm Repair: Outcomes From a National Multicenter Registry

INTRODUCTION

Women are generally underrepresented in trials focusing on aortic aneurysm. Nevertheless, sex-related differences have recently emerged from several studies and registries. The aim of this research was to assess whether sex-related anatomical disparities existed in fenestrated and branched aortic repair candidates and whether these discrepancies could influence endovascular repair outcomes.

METHODS

Data from all consecutive patients treated during the 2008-2019 period within the Italian Multicenter fenestrated or branched endovascular aortic repair (F/BEVAR) Registry were included in the present study. Propensity matching was performed using a logistic regression model adjusted for demographic data and comorbidities to obtain comparable male and female samples. The selection model led to a final study population of 176 patients (88 women and 88 men) among the total initial cohort of 596. Study endpoints were technical and clinical success, overall survival, aneurysm-related death, and reintervention rates evaluated at 30 days and during follow-up.

RESULTS

Twenty-eight patients (15.9%) received urgent/emergent repair. In most of the cases (71.6%), women received treatment for extensive thoracoabdominal pathology (Crawford type I, II, or III aneurysm rather than type IV or juxta-pararenal) versus 46.6% of men (p=0.001). Female patients presented with more challenging iliac accesses with at least one side considered hostile in 27.3% of the cases (vs 13.6% in male patients, p=0.039). Finally, women had significantly smaller visceral vessels. Women had significantly worse operative outcomes, with an 86.2% technical success rate versus 96.6% in the male population (p=0.016). No differences were recorded in terms of 30-day reinterventions between men and women. The 5-year estimate of freedom from late reintervention, according to Kaplan-Meier analysis, was 85.6% in men versus 81.6% in women (p=ns). No aneurysm-related death was recorded during follow-up (median observational time, 23 months [interquartile range, 7-45 months]).

CONCLUSION

Women presented a significantly higher incidence of thoracoabdominal aneurysms, smaller visceral vessels, and more complex iliofemoral accesses, resulting in a significantly lower technical success after F/BEVAR. Further studies assessing sex-related differences are needed to properly determine the impact on outcomes and stratify procedural risks.

CLINICAL IMPACT

Women are generally underrepresented in trials focusing on aortic aneurysms. Aiming to assess whether sex may affect outcomes after a complex endovascular aortic repair, a propensity score selection was applied to a total population of 596 patients receiving F/BEVAR aortic repair with the Cook platform, matching each treated female patient with a corresponding male patient. Women presented more frequently a thoracoabdominal aneurysm extent, smaller visceral vessels, and complex iliofemoral accesses, resulting in significantly worse operative outcomes, with an 86.2% technical success versus 96.6% (p=0.016). No differences were recorded in terms of short-term and mid-term reinterventions. According to these results, careful and critical assessment should be posed in case of female patients receiving complex aortic repair, especially regarding preoperative anatomical evaluation and clinical selection with appropriate surgical risk stratification.

Ten-year single-center outcomes following endovascular repair for abdominal aortic aneurysm using the INCRAFT device

OBJECTIVE

This study aimed to report the long-term outcomes beyond 10 years of endovascular aneurysm repair (EVAR) for abdominal aortic aneurysms using the low-profile INCRAFT device.

METHODS

This was a single-center, retrospective cohort study of all patients undergoing EVAR using the INCRAFT device as part of the regulatory trial between 2012 and 2013. Primary endpoint was aneurysm-related death. Secondary endpoints were all-cause death, reintervention, late open conversion, and aneurysm status (shrinkage, stable, and growth).

RESULTS

Thirty patients with a mean age of 71.8 ± 7.7 years were included in this study. The median aneurysm diameter at EVAR was 54.5 mm (interquartile range, 53-56.8 mm). All abdominal aortic aneurysms in this study were treated following the device's instructions for use. At index EVAR, the INCRAFT device was successfully implanted in all patients using a percutaneous approach under local anesthesia. No patients experienced major adverse events or procedure-related complications 30 days after EVAR. During the median follow-up of 125 months (interquartile range, 98-131 months) with follow-up rates of 100% at 5 years and 96.7% at 10 years, aneurysm-related mortality was 0%, and freedom from all-cause mortality was 82.9% at 5 years and 75.3% at 10 years. Reintervention was required in 10 patients with 15 procedures. Sac growth was observed in 11 patients (36.7%), six of whom eventually required late open conversion; five of these patients underwent open aneurysmorrhaphy with stent graft preservation, and one underwent open surgical repair with endograft explantation. Late rupture was identified in one case, where type Ia endoleak led to rupture at 69 months, and open repair was successfully performed. Freedom from reintervention was 89.0% at 5 years but declined to 60.9% at 10 years; freedom from late open conversion was 100% at 5 years but declined to 70.8% at 10 years.

CONCLUSIONS

Long-term outcomes of the INCRAFT stent graft showed no aneurysm-related deaths. However, sac growth occurred persistently throughout the follow-up period, resulting in a relatively high rate of reinterventions in the later periods, which highlights the importance of lifelong postoperative surveillance and appropriate reinterventions when indicated.

Systematic Review Examining the Association Between Angiotensin Converting Enzyme Inhibitor or Angiotensin Receptor Blocker Prescription and Abdominal Aortic Aneurysm Growth and Events

OBJECTIVE

Whether angiotensin II blockade is an effective medical treatment for abdominal aortic aneurysms (AAAs) has not been established. This systematic review and meta-analysis aimed to determine the association between angiotensin converting enzyme inhibitor (ACEi) or angiotensin receptor blocker (ARB) prescription and AAA growth and events.

DATA SOURCES

MEDLINE, Embase, Scopus, Web of Science, and the Cochrane Library databases were searched from their inception to 4 January 2024, with no language restrictions.

REVIEW METHODS

The five databases were searched for randomised controlled trials (RCTs) and observational studies reporting the association between ACEi or ARB prescription and AAA growth, repair, or rupture. The primary outcome was AAA growth, with secondary outcomes of AAA rupture, AAA repair, and AAA related events (rupture and repair combined). Risk of bias was assessed using the Risk of Bias 2 tool for RCTs and with a modified Newcastle-Ottawa scale for observational studies. Certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE). Random effects models were used for meta-analyses.

RESULTS

Eleven studies (two RCTs, eight observational studies, and one meta-analysis of individual patient data from seven populations) involving 58 022 patients were included. ACEi prescription was not associated with a statistically significant reduction in AAA growth (standard mean difference 0.01 mm/year, 95% confidence interval [CI] -0.26 - 0.28; p = .93; I2 = 98%) or AAA repair (odds ratio [OR] 0.73, 95% CI 0.50 - 1.09; p = .65; I2 = 61%), but was associated with a statistically significantly lower risk of AAA rupture (OR 0.87, 95% CI 0.81 - 0.93; p < .001; I2 = 26%) and AAA related events (OR 0.82, 95% CI 0.72 - 0.95; p = .006; I2 = 80%). ARB prescription was not associated with significantly reduced AAA growth or a lower risk of AAA related events. The two RCTs had a low risk of bias, with one observational study having low, seven moderate, and one high risk of bias. All of the findings had a very low certainty of evidence based on the GRADE analysis.

CONCLUSION

There was no association between ACEi or ARB prescription and AAA growth, but ACEi prescription was associated with a reduced risk of AAA rupture and AAA related events with very low certainty of evidence.

Aorto-uni-iliac stent grafts without crossover fem-fem bypass for treatment of abdominal aortic aneurysms: A report of two cases

INTRODUCTION AND IMPORTANCE

Arterial aneurysm is a serious condition caused by weakened arterial walls. Aorto-uni-iliac (AUI) and femorofemoral bypass are safe and effective options for managing abdominal aortic aneurysm (AAA). However, fem-fem bypass leads to longer surgical procedures and introduces additional risks such as graft infection, occlusion, wound complications, and peripheral vascular problems. This report highlights two successful cases of AAA management using the AUI approach without the need for fem-fem bypass.

CASE PRESENTATION

Two male patients, both aged about 70, presented at our medical facility complaining of abdominal pain. Investigations unveiled an approximately 10-cm AAA that was previously undetected. Subsequently, we performed an elective AUI procedure without fem-fem bypass, marking the first instance of this technique being employed in Iran successfully.

CLINICAL DISCUSSION

The placement of an AUI stent graft is generally less technically demanding compared to that of a standard bifurcated graft, especially when anatomical constraints are severe, making the latter difficult or even impossible to deploy. Beside the longer duration of stent deployment, sometimes we encounter contralateral complications to cannulate the main body. The AUI is typically used in emergency situations or when the distal aorta's internal diameter is small. The femoral-femoral bypass is advised in nearly all circumstances.

CONCLUSION

AUI stent grafts are still a viable option for treatments of AAA, especially in cases of severe aortoiliac occlusive disease or comorbidities. AUI without crossover bypass is a viable option in the patients who have stenosis of contralateral iliac artery.

Abdominal aneurysm sac thrombus CT density and volume after EVAR: which association with underlying endoleak?

BACKGROUND

Our aim was to analyse abdominal aneurysm sac thrombus density and volume on computed tomography (CT) after endovascular aneurysm repair (EVAR).

METHODS

Patients who underwent EVAR between January 2005 and December 2010 and had at least four follow-up CT exams available over the first five years of follow-up were included in this retrospective single-centre study. Thrombus density and aneurysm sac volume were calculated on unenhanced CT scans. Linear mixed models were used for data analysis.

RESULTS

Out of 82 patients, 44 (54%) had an endoleak on post-EVAR contrast-enhanced CT. Thrombus density significantly increased over time in both the endoleak and non-endoleak groups, with a slope of 0.159 UH/month (95% confidence interval [CI] 0.115-0.202), p < 0.0001) and 0.052 UH/month (95% CI 0.002-0.102, p = 0.041). In patients without endoleak, a significant decrease in aneurysm sac volume was identified over time (slope -0.891 cc/month, 95% CI -1.200 to -0.581); p < 0.001) compared to patients with endoleak (slope 0.284 cc/month, 95% CI -0.031 to 0.523, p = 0.082). The association between thrombus density and aneurysm sac volume was positive in the endoleak group (slope 1.543 UH/cc, 95% CI 0.948-2.138, p < 0.001) and negative in the non-endoleak group (slope -1.450 UH/cc, 95% CI -2.326 to -0.574, p = 0.001).

CONCLUSION

We observed a progressive increase in thrombus density of the aneurysm sac after EVAR in patients with and without endoleak, more pronounced in patients with endoleak. The association between aneurysm volume and thrombus density was positive in patients with and negative in those without endoleak.

RELEVANCE STATEMENT

A progressive increase in thrombus density and volume of abdominal aortic aneurysm sac on unenhanced CT might suggest underlying endoleak lately after EVAR.

KEY POINTS

Thrombus density of the aneurysm sac after EVAR increased over time. Progressive increase in thrombus density was significantly associated to the underlying endoleak. The association between aneurysm volume and thrombus density was positive in patients with and negative in those without endoleak.

[Abdominal aortic malformation in 2 dogs]

Aneurysms of the abdominal aorta are only sporadically documented in the veterinary literature. This publication describes 2 canine cases in which abdominal aortic malformation was detected by sonography and confirmed by computed tomography. In one case a histological diagnosis of an aortic aneurysm was possible.One dog showed posterior weakness, in the second dog the aortic aneurysm had been noticed sonographically during a routine examination.In the patient with the proven aortic aneurysm, it may be presumed that a hemodynamically relevant component in consequence to the altered flow profile and occurring turbulence exists. In accordance with human medical standards, regular monitoring of these patients, both clinically and by ultrasound, would therefore appear to be useful in order to be able to detect the occurrence or progression of secondary hemodynamic changes and possible thrombus formation at an early stage. In contrast, the second case presented here has not shown any clinical signs with regard to the abdominal vascular malformation up to the present time.

Circulating monocyte populations as biomarker for abdominal aortic aneurysms: a single-center retrospective cohort study

Background

Abdominal aortic aneurysm (AAA) development is driven by inflammation, in particular myeloid cells, which represent attractive biomarker candidates. Yet to date, the maximum aortic diameter is the only clinically applied predictor of AAA progression and indicator for surgical repair. We postulated that aortic inflammation is reflected in a systemic change of monocyte populations, which we investigated regarding marker potential in AAA diagnosis and prognosis.

Methods

We conducted a single-center retrospective cohort study in a diagnostic setting, measuring monocyte subsets by flow cytometry in peripheral blood samples of 47 AAA patients under surveillance, matched with 25 healthy controls and 25 patients with peripheral artery disease (PAD). In a prognostic setting, we acquired longitudinal data of 60 AAA patients including aneurysm growth assessment by computed tomography at 6-month intervals.

Results

Blood levels of total monocytes, CD16+ monocytes and particularly intermediate monocytes were significantly increased in AAA patients versus healthy individuals and were also elevated compared to PAD patients. The combination of intermediate monocyte and D-dimer blood levels outperformed the individual diagnostic marker values. Additionally, the elevated concentrations of total monocytes, intermediate monocytes, and monocyte-platelet aggregates (MPA) were suited to predict rapid AAA progression over short-term periods of six months. Of note, MPA were identified as independent predictor of AAA disease progression in multivariable analysis.

Conclusion

Circulating monocyte subsets are elevated in AAA patients and support diagnosis and prediction of aneurysm progression. Monocyte subsets and D-dimer reflect different hallmarks (inflammation and hemostasis) of AAA pathology and when combined, may serve as improved biomarker.

Early Opioid Use and Postoperative Delirium Following Open Abdominal Aortic Aneurysm Repair

BACKGROUND

Postoperative delirium is a common complication following open abdominal aortic aneurysm repair (OAR). Opioids have been found to contribute to delirium, especially at higher doses. This study assessed the impact of early postoperative opioid analgesia on postoperative delirium incidence and time to onset. We hypothesized that higher early postoperative opioid utilization would be associated with increased postoperative delirium incidence.

METHODS

This was a retrospective analysis of OAR cases at a single quaternary care center from years 2012-2020. The primary exposure was oral morphine equivalents use (OME), calculated for postoperative days 1-7. A cut point analysis using a receiver operator curve for postoperative delirium determined the threshold for high OME (OME>37 mg). The primary outcome was postoperative delirium incidence identified via chart review. Multivariable logistic regression was performed for postoperative delirium and adjusted for covariates meeting P < 0.1 on bivariate analysis.

RESULTS

Among 194 OAR cases, 67 (35%) developed postoperative delirium with median time to onset of 3 days (IQR = 2-6). Patients with postoperative delirium were older (74 years vs. 69 years), more frequently presented with symptomatic AAA (47% vs. 27%) and had a higher proportion of comorbidities (all P < 0.05). Cases with high OME utilization on postoperative day 1 (55%) were younger (69 vs. 73 years), less frequently had an epidural (46% vs. 77%), and more frequently developed delirium (42% vs. 25%, all P < 0.05). Epidural use was associated with a significant decrease in OME utilization on postoperative day 1 (33 vs. 83, P < 0.01). Postoperative delirium onset was later in those with high OME use (4 vs. 2 days, P = 0.04). On multivariable analysis, high OME remained associated with postoperative delirium (Table II).

CONCLUSIONS

High opioid utilization on postoperative day 1 is associated with increased postoperative delirium and epidural along with acetaminophen use reduced opioid utilization. Future study should examine the impact of opioid reduction strategies on outcomes after major vascular surgery.

Polygenic Risk Score Informed Clinical Model for Improving Abdominal Aortic Aneurysm Screening

BACKGROUND

Abdominal aortic aneurysm (AAA) is a complex disease with environmental and genetic risk factors. Polygenic risk scores (PRSs) based on disease-specific risk-associated single nucleotide variants (SNVs) have demonstrated effectiveness in stratifying individual-level disease risk for cardiovascular diseases. This prospective cohort study assessed associations of PRS of AAA (PRSAAA) with risk of incident AAA, analyzed the effectiveness of a combined clinical-genetic risk model, and explored the clinical utility of the model in identifying high-risk individuals for AAA screening.

METHODS

PRSAAA was calculated using 911,440 SNVs and PRS of coronary artery disease was calculated using 2,324,683 SNVs derived from mixed ancestry genome-wide association studies. The UK Biobank was used as the study cohort. All individuals with complete genetic data available and no diagnosis of AAA at the time of recruitment were included in the analysis and followed prospectively to assess for incident AAA. A PRS-informed clinical model, Prob-AAA, was developed using clinically significant variables and PRSAAA.

RESULTS

Four hundred eighty-one thousand one hundred 5 individuals were included in the analysis with 2,668 incident AAA cases. Incident AAA increased from 0.30 to 0.93% between the lowest and highest decile of PRSAAA; similarly, severe AAA, requiring surgery and/or presenting with rupture, increased from 23 to 39% of incident AAA cases across deciles. PRSAAA was a predictor of incident AAA diagnosis (hazard ratio 2.06 [1.70-2.48]) independent of other clinical risk factors including male sex, older age, and smoking history. Prob-AAA was an independent predictor of incident AAA (hazard ratio 1.92 [1.69-2.20]), and identified 9.6% of cases of incident AAA compared to only 4.2% by PRSAAA. Current screening guidelines captured 5.7% of the overall cohort, with an incident AAA rate of approximately 3.2%. Among males not included by current guidelines, Prob-AAA identified an additional cohort, approximately 2% of the overall cohort, with a similar rate of incident AAA.

CONCLUSIONS

Prob-AAA, a PRS-informed clinical model for AAA, improved upon the predictive power of current, clinical risk factor-informed, screening guidelines for AAA.

Socioeconomic Status Based on Area Deprivation Index Does Not Affect Postoperative Outcomes in Patients Undergoing Endovascular Aortic Aneurysm Repair in the VA Health-Care System

BACKGROUND

Living conditions and socioeconomic status are known to impact individual health and access to medical care. Prior research has validated the Area Deprivation Index (ADI) tool as a measure of socioeconomic disadvantage for a given locality. Living in a neighborhood with a higher ADI score has been associated with increased rates of hospital readmission due to complications following surgery. We set forth to identify the possible associations between a patient's ADI score and postoperative endovascular aneurysm repair (EVAR) outcomes in the Veterans Health Care Administration (VHA).

METHODS

We retrospectively analyzed the outcomes of patients who underwent EVAR from January 2010 to December 2021 at a level 1A VHA Hospital. Patient demographics and intraoperative variables were obtained. ADI score was calculated based on home addresses and resulted in a local score on a scale of 1-10 and a national percentile on a scale of 1-100. We then further stratified these patients into local and national quintile groups. Local ADI 1 included scores of 1-2, and local ADI 5 included scores of 9-10. National ADI 1 comprised scores 1-20, and national ADI 5 scored 81-100. The other scores were equally divided into ADI 2, 3, and 4. Higher ADI scores were associated with lower socioeconomic status. We identified clinical outcomes, including wound infection, respiratory failure, urinary tract infection, acute kidney injury, limb stenosis, readmission, length of stay, and subsequent reintervention rates.

RESULTS

241 patients underwent EVAR over the time period examined. 57.3% (n = 138) of patients were in quintiles 4 and 5 for local ADI; when national ADI percentiles organized these same patients, 47.3% (n = 114) were in quintiles 4 and 5. Patient demographics did not vary between the local and national groups. We saw no statistically significant difference in intraoperative variables, postoperative complications, readmission, loss to follow-up, or 1-year mortality rates across ADI quintiles at the local or national level. Binary Logistic Regression showed no statistical significance for local and national ADI quintiles for hospital readmission and overall postoperative complications.

CONCLUSIONS

We found that there was no statistical significance between hospital readmission rates or worse surgical outcomes across local and national ADI quintiles. This suggests that the VHA resources and multidisciplinary support may improve care across neighborhoods. This comprehensive care provided at VHA may mitigate postoperative complications in patients undergoing EVARs. Further research is warranted to investigate the role of area deprivation in health care and EVAR outcomes in a veteran population.

On the feasibility of ultrasound Doppler-based personalized hemodynamic modeling of the abdominal aorta

BACKGROUND

Personalized modeling is a promising tool to improve abdominal aortic aneurysm (AAA) rupture risk assessment. Computed tomography (CT) and quantitative flow (Q-flow) magnetic resonance imaging (MRI) are widely regarded as the gold standard for acquiring patient-specific geometry and velocity profiles, respectively. However, their frequent utilization is hindered by various drawbacks. Ultrasound is used extensively in current clinical practice and offers a safe, rapid and cost-effective method to acquire patient-specific geometries and velocity profiles. This study aims to extract and validate patient-specific velocity profiles from Doppler ultrasound and to examine the impact of the velocity profiles on computed hemodynamics.

METHODS

Pulsed-wave Doppler (PWD) and color Doppler (CD) data were successfully obtained for six volunteers and seven patients and employed to extract the flow pulse and velocity profile over the cross-section, respectively. The US flow pulses and velocity profiles as well as generic Womersley profiles were compared to the MRI velocities and flows. Additionally, CFD simulations were performed to examine the combined impact of the velocity profile and flow pulse.

RESULTS

Large discrepancies were found between the US and MRI velocity profiles over the cross-sections, with differences for US in the same range as for the Womersley profile. Differences in flow pulses revealed that US generally performs best in terms of maximum flow, forward flow and ratios between forward and backward flow, whereas it often overestimates the backward flow. Both spatial patterns and magnitude of the computed hemodynamics were considerably affected by the prescribed velocity boundary conditions. Larger errors and smaller differences between the US and generic CFD cases were observed for patients compared to volunteers.

CONCLUSION

These results show that it is feasible to acquire the patient-specific flow pulse from PWD data, provided that the PWD acquisition could be performed proximal to the aneurysm region, and resulted in a triphasic flow pattern. However, obtaining the patient-specific velocity profile over the cross-section using CD data is not reliable. For the volunteers, utilizing the US flow profile instead of the generic flow profile generally resulted in improved performance, whereas this was the case in more than half of the cases for the patients.

Complications and Technical Success on Upper Limb Vascular Access for Endovascular Repair of Complex Abdominal and Thoraco-abdominal Aortic Aneurysms: A Systematic Review and Meta-Analysis

BACKGROUND

Catheterization of target vessels (TV) represented by renal visceral vessels are the crucial aspect during fenestrated and branched endovascular repair. This study aims to assess the efficacy and complications associated with upper limb catheterization during complex aneurysm endovascular surgery repair.

METHODS

A systematic review was conducted after Preferred Reporting Items for a Systematic Review and Meta-analysis (PRISMA) guidelines, involving a search across PubMed, Cochrane CENTRAL, and Web of Science. Primary endpoint was represented by 30-day stroke. Secondary endpoints were target vessels' (TVs) technical success, 30-day mortality, and local access-related complications. Meta-analyses were performed using a random-effects model.

RESULTS

Sixteen observational studies encompassing 4,137 patients were included. The 30-day stroke incidence for upper limb access was 1.4% (95% CI 1.0-1.8%), which was slightly higher than lower limb, despite not statistically significant. Mortality varied between 0 and 6.8%, and local access-related complications occurred in 3.2% (95% CI 1.9-4.4%). Technical success in TV catheterization was 99.2% (95% CI 98.4-100.0%).

CONCLUSIONS

This systematic review and meta-analysis demonstrate the safety and efficacy of upper limb access for Fenestrated and Branched Endovascular Aortic Repair (f/b-EVAR), with low stroke risk, mortality rates, and minimal local complications. Despite the risk of bias, the findings suggest that upper limb access may be beneficial, especially in bailout situations when femoral access fails, offering valuable insights for clinical decision-making.

An Expert-Based Review on the Relevance and Management of Type 2 Endoleaks Following Endovascular Repair of Ruptured Abdominal Aortic Aneurysms

Ruptured abdominal aortic aneurysms (rAAAs) are life-threatening and require emergent surgical therapy. Endovascular aortic repair for rupture (rEVAR) has become the leading strategy due to its minimal invasive approach with expected lower morbidity and mortality, especially in patients presenting with hemodynamic instability and relevant comorbidities. Following rEVAR, intraoperative angiography or early postinterventional computed tomography angiography have to exclude early type 1 or 3 endoleaks requiring immediate reintervention. Persistent type 2 endoleaks (T2ELs) after rEVAR, in contrast to elective cases, can cause possibly lethal situations due to continuing extravascular blood loss through the remaining aortic aneurysm rupture site. Therefore, early identification of relevant persistent T2ELs associated with continuous bleeding and hemodynamic instability and immediate management is mandatory in the acute postoperative setting following rEVAR. Different techniques and concepts for the occlusion of T2ELs after rEVAR are available, and most of them are also used for relevant T2ELs after elective EVAR. In addition to various interventional embolization procedures for persistent T2ELs, some patients require open surgical occlusion of T2EL-feeding arteries, abdominal compartment decompression or direct surgical patch occlusion of the aneurysm rupture site after rEVAR. So far, in the acute situation of rAAAs, indications for preemptive or intraoperative T2EL embolization during rEVAR have not been established. In the long term, persistent T2ELs after rEVAR can lead to continuous aneurysm expansion with the possible development of secondary proximal type I endoleaks and an increased risk of re-rupture requiring regular follow-up and early consideration for reintervention. To date, only very few studies have investigated T2ELs after rEVAR or compared outcomes with those from elective EVAR regarding the special aspects of persisting T2ELs. This narrative review is intended to present the current knowledge on the incidence, natural history, relevance and strategies for T2EL management after rEVAR.

Nationwide analysis of EVAR explantation outcomes in Korea: A comprehensive dataset study

OBJECTIVE

Endovascular aortic aneurysm repair (EVAR) is the primary treatment for abdominal aortic aneurysms, constituting 70%-80% of interventions. Despite initial benefits, long-term studies show increased mortality. Using nationwide data, this study assesses outcomes of EVAR, open aortic repair (OAR), and EVAR explantation (EE) in Korea, while exploring characteristics of late open conversion, including the rising EE incidence.

METHODS

Employing the National Health Insurance Service database, covering health-related data for nearly 50 million Koreans, the study spanned from 2002 to 2020. Patients with AAA diagnoses (I71.3 or I71.4) were categorized into OAR, EVAR, and EE groups based on procedural codes. Statistical analyses, including t-tests, Fisher's exact tests, Cox proportional hazard models, and multivariate Cox regression, assessed baseline characteristics, mortality risks, and factors within the EE group.

RESULTS

The analysis encompassed 26,195 patients, with 66.19% in the EVAR group, 31.87% in the OAR group, and 1.94% in the EE group. EVAR cases steadily increased from 2002 to 2018. Survival rates favored EVAR, followed by OAR and EE. 30-day survival was lower in EE than EVAR. Multivariate analysis for EE revealed no risk factors for 30-days survival but identified age, chronic kidney disease, high Charlson Comorbidity Index scores, and less than 6 months since EVAR as risk factors for overall mortality.

CONCLUSION

Rising EE trends with increased EVAR adoption, particularly evident in the Korean dataset, underscore inferior outcomes. This highlights the critical need for strategic initial treatment decisions and timely interventions to enhance overall results and mitigate the unfavorable EE incidence.

Understanding Type II Endoleak: A Harmless Imaging Finding or a Silent Threat?

Type II endoleak (T2EL) represents a challenging clinical entity following endovascular abdominal aortic aneurysm repair (EVAR). Although several studies have suggested that T2ELs are related to an increased risk of aneurysm sac growth and subsequent rupture, the exact role that T2ELs play in long-term outcomes remains debatable. Understanding the pathophysiology, diagnostic modalities, and management options of T2ELs is important for patients' safety and proper resource utilization. While conservative management may be suitable for asymptomatic patients with a stable aneurysm size, interventional approaches, including transarterial embolization, direct sac puncture embolization and open conversion have been described for patients with persistent T2EL associated with sac expansion. However, more research is needed to better determine the clinical benefit of such interventions. A thorough evaluation of all endoleak types before T2EL treatment would be reasonable for patients with T2ELs associated with sac expansion. Further studies are needed to refine treatment strategies aimed at minimizing T2EL-related complications. Collaborative efforts among vascular specialists, radiologists, and researchers are of paramount importance to address this ongoing clinical challenge.

Endovascular repair for infra-renal aortic aneurysms with supra-renal fixation endoprosthesis: Results and outcomes

OBJECTIVE

The main objective of this paper is to evaluate the outcomes regarding endoleaks, reinterventions, and death related to aneurysm complications in patients submitted to endovascular repair (EVAR) for abdominal aortoiliac aneurysm (AAA) using Endurant II (Medtronic) and Zenith Flex (Cook) endografts.

METHODS

This was a prospective, consecutive cohort study of patients with AAA who underwent EVAR with the use of Endurant II stent graft and Zenith Flex endograft.

RESULTS

A total of 156 patients submitted to EVAR were evaluated. The perioperative mortality was 5.1%, 8 patients. The median clinical follow-up period was 760 ± 80 days. There were 28 patients (17.9%) submitted to urgent repair of the aneurysm (symptomatic expansion or rupture) and 128 patients (82.1%) submitted to elective repair. There were 36 cases (23.1%) of later endoleak and most of them are Type II endoleaks (21 patients, 13.4%). There were 12 cases of Type I endoleak. Moreover, regarding limb graft occlusion (LGO), there were 9 patients (5.8%). The overall survival rate in Kaplan-Meier analysis at 720 days was 84.8% in the total cohort. The freedom from reintervention rate in Kaplan-Meier analysis at 720 days was 92.7% in the total cohort. The linear regression analysis for survival rates showed that chronic kidney disease (p = .03; hazard ratio (HR) = 2.82, CI = 1.07-4.44) was the only factor related to poorer survival rates in both univariate and multivariate analyses. The linear regression analysis showed that the presence of endoleaks (p < .001, HR = 6.69, CI = 2.26-8.48) and limb graft occlusion (p < .001, HR = 8.02, CI = 1.60-9.99) were related to reintervention in both univariate and multivariate analyses.

CONCLUSION

In this present study, supra-renal fixation endograft devices were safe and efficient in treating AAA, with satisfactory results and no renal compromise. The linear regression analysis showed that the presence of endoleaks and limb graft occlusion were related to higher reintervention rates in both univariate and multivariate analyses.

Computational Hemodynamics-Based Growth Prediction for Small Abdominal Aortic Aneurysms: Laminar Simulations Versus Large Eddy Simulations

Prior studies have shown that computational fluid dynamics (CFD) simulations help assess patient-specific hemodynamics in abdominal aortic aneurysms (AAAs); patient-specific hemodynamic stressors are frequently used to predict an AAA's growth. Previous studies have utilized both laminar and turbulent simulation models to simulate hemodynamics. However, the impact of different CFD simulation models on the predictive modeling of AAA growth remains unknown and is thus the knowledge gap that motivates this study. Specifically, CFD simulations were performed for 70 AAA models derived from 70 patients' computed tomography angiography (CTA) data with known growth status (i.e., fast-growing [> 5 mm/yr] or slowly growing [< 5 mm/yr]). We used laminar and large eddy simulation (LES) models to obtain hemodynamic parameters to predict AAAs' growth status. Predicting the growth status of AAAs was based on morphological, hemodynamic, and patient health parameters in conjunction with three classical machine learning (ML) classifiers, namely, support vector machine (SVM), K-nearest neighbor (KNN), and generalized linear model (GLM). Our preliminary results estimated aneurysmal flow stability and wall shear stress (WSS) were comparable in both laminar and LES flow simulations. Moreover, computed WSS and velocity-related hemodynamic variables obtained from the laminar and LES simulations showed comparable abilities in differentiating the growth status of AAAs. More importantly, the predictive modeling performance of the three ML classifiers mentioned above was similar, with less than a 2% difference observed (p-value > 0.05). In closing, our findings suggest that two different flow simulations investigated did not significantly affect outcomes of computational hemodynamics and predictive modeling of AAAs' growth status, given the data investigated.

Endovascular Aortic Balloon control versus open Aortic cross Clamp in open ruptured abdominal Aortic aneurysm repair

BACKGROUND

To determine 30-day mortality of endovascular aortic balloon control compared with open aortic cross clamp in open surgical repair (OSR) of ruptured abdominal aortic aneurysms (rAAAs).

METHODS

A retrospective cohort review was performed of all adult patients who underwent OSR of an infrarenal rAAA between 2001 and 2018 at a single tertiary care center. A total of 174 patients were identified, of which 21 patients received endovascular aortic balloon control and 137 patients received an open aortic cross clamp. Primary outcome was 30-day mortality. Two-variable multivariate logistic regression was adjusted for preoperative blood pressure and age.

RESULTS

Endovascular aortic balloon control was nonsignificantly associated with lower mortality (adjusted odds ratio [OR] = 0.75 (95% confidence interval [CI] 0.24 to 2.38), P = 0.63), and when placed under local anesthesia showed a trend toward improved mortality (adjusted OR = 0.34 (95%CI 0.06 to 1.77), P = 0.19). Balloon placement under general anesthesia was nonsignificantly associated with worse mortality (adjusted OR = 2.50 (95%CI 0.35 to 9.13), P = 0.46).

CONCLUSIONS

There is no significant difference in mortality with the use of endovascular aortic balloon control in rAAA patients undergoing OSR, and it may be considered as an alternative approach to open aortic cross clamp in properly selected patients.

Analysis of high-risk factors and mortality prediction of ruptured abdominal aortic aneurysm

INTRODUCTION

Ruptured abdominal aortic aneurysms (RAAAs) are among the most dangerous emergencies in vascular surgery, with a high death rate and numerous risk factors influencing perioperative death. Therefore, identifying the critical risk factors for RAAAs is crucial to increasing their survival rate. Our aim was to identify those risk factors from a wide range of parameters.

METHODS

Retrospective analysis of hospitalised RAAA patients treated at this center between May 2004 and January 2023. After comparing the preoperative data of patients who survived and those who died, high-risk characteristics influencing the perioperative care of RAAA patients were identified, and logistic regression analysis was carried out. The mean follow-up time was 45.34 months.

RESULTS

During the study period, a total of 155 patients (average age 67.4±71.93 years, 123 (78.85%)males, 32 (20.51%)females) were enrolled. The patients participating in the group were divided into survival group (n = 123) and death group (n = 27). The main differences included hemodynamic instability (51.9% vs 28.5%; P=0.019), sudden cardiac arrest (14.8% vs 1.6%; P=0.010), deterioration of consciousness (40.7% vs 17.1%; P=0.007), renal impairment (22.2% vs 2.4%; P=0.001), chronic kidney disease (18.5% vs3.2%; P=0.010). There is also a history of cancer (Ca) (18.5% vs 4.1%; P=0.021). Risk factors for Endovascular aneurysm repair (EVAR) include diastolic blood pressure ≤ 50 mmHg (36.4% vs 8.0%; P=0.025), renal function impairment (18.2% vs 0; P=0.015), and chronic kidney disease (27.3% vs 4.0%; P=0.028). Risk factors for open surgical repair (OSR) include diastolic blood pressure ≤ 50 mmHg (40.0% vs 6.3%; P=0.014). Finally, the above statistically significant factors were analyzed by Logistic regression analysis, and it was found that diastolic blood pressure ≤ 50mmHg, cardiac arrest, renal function damage and Ca history were independent risk factors. We followed 123 individuals and 14 were lost to follow-up, with an overall survival rate of 43.8%.

CONCLUSION

Hemodynamics, which includes shock, blood pressure, cardiac arrest, deterioration of consciousness, and other conditions, are the primary risk factors for the perioperative death of a ruptured abdominal aortic aneurysm. Simultaneously, diastolic blood pressure ≤50mmHg was found to be associated with risk factors for OSR, whereas renal function impairment, chronic renal illness, and diastolic blood pressure ≤50mmHg were associated with risk for EVAR.

Prophylactic Mesh Reinforcement Versus Primary Suture for Abdominal Wall Closure after Elective Abdominal Aortic Aneurysm Repair with Midline Laparotomy Incision: Updated Systematic Review Including Time-To-Event Meta-Analysis and Trial Sequential Analysis of Randomized Controlled Trials

BACKGROUND

Patients undergoing open abdominal aortic aneurysm (AAA) repair have a high risk of incisional hernia. Heterogeneity in recommendations regarding prophylactic mesh reinforcement between scientific society guidelines reflects the lack of sufficient data, with the Society for Vascular Surgery making no recommendation on methods for abdominal wall closure. We aimed to synthesize the most current evidence on mesh versus primary suture abdominal wall closure after open AAA repair.

METHODS

A systematic review was conducted on randomized controlled trials (RCTs) comparing mesh reinforcement with primary abdominal wall closure for patients who underwent elective AAA repair with a midline laparotomy incision. Dichotomous and time-to-event data were pooled using random effects models, applying the Mantel-Haenszel or inverse variance statistical method. The revised Cochrane tool and Grades of Recommendation, Assessment, Development, and Evaluation framework were used to assess the risk of bias and certainty of evidence, respectively. Trial sequential analysis assumed alpha = 5% and power = 80%.

RESULTS

Five RCTs were included reporting a total of 487 patients (260 in the mesh group and 227 in the primary suture group). Patients who had mesh closure had statistically significantly lower odds of developing incisional hernia after open AAA repair than those with primary suture closure (odds ratio (OR) 0.20, 95% confidence interval (CI) 0.09-0.43). Time-to-event analysis confirmed that the hazard of incisional hernia was statistically significantly lower in patients who had mesh closure (P < 0.05). Meta-analysis found statistically significantly lower odds of reoperation for incisional hernia in the mesh group (OR 0.23, 95% CI 0.06-0.93), but there was no statistically significant difference in wound infection (risk difference 0.02, 95% CI -0.03-0.08). The overall risk of bias was low in one study, high in 2 studies, "some concerns" in 2 studies for incisional hernia and reoperation for incisional hernia, and high in all studies reporting wound infection. The certainty of evidence was judged to be low for all outcomes. Trial sequential analysis confirmed a benefit of mesh reinforcement in reducing the risk of incisional hernia.

CONCLUSIONS

Meta-analysis of the highest-level data demonstrated a benefit of prophylactic mesh reinforcement, with trial sequential analysis confirming no additional RCTs required. This provides compelling evidence to support the use of mesh for midline laparotomy closure in patients undergoing open AAA repair.

Contemporary Experience of the Neo-Aortoiliac System (NAIS) Procedure: A Case Series with Review of the Literature

OBJECTIVES

Aortic graft infection (AGI) is a life-threatening complication that can result in death, amputation, sepsis, aorto-enteric fistula, and pseudoaneurysm formation. After explantation of the infected graft, options for reconstruction include extra-anatomic bypass or in-line reconstruction using antibiotic-coated prosthetic graft, cryopreserved allograft, or a neo-aortoiliac system (NAIS) using autogenous femoral veins. While the NAIS procedure has shown promising results, there is relatively limited clinical experience due the magnitude and morbidity of the surgery. In this study, we reviewed our single-center experience using the NAIS procedure and performed a systematic review of the contemporary literature more than the past decade.

METHODS

A retrospective review was performed on all patients undergoing NAIS reconstruction with autogenous femoral vein conduits at a single institution from 2010 to 2022. Pubmed, Embase, and Cochrane Library databases were queried for studies published from 2012 to 2022 to identify those reporting on outcomes of patients undergoing the NAIS procedure. Outcome variables included early and late mortality, major complications including amputation, graft or conduit related complications, re-infection, and re-intervention. Additional variables collected include patient demographics, operative technique, and follow up.

RESULTS

There were 14 patients included in our case series with 30-day mortality of 21%. At a mean follow up of 22 months, complication rate was 64.3%, re-intervention rate was 14.3%, re-infection rate was 7.1%, and amputation rate was 7.1%. On review of the literature, 12 studies ultimately met criteria to be included in analysis with a combined total of 368 patients. Pooled averages included 30-day mortality of 9.0%, re-intervention rate of 20.5%, re-infection rate of 5.6%, and amputation rate of 6.5%.

CONCLUSIONS

The NAIS procedure for management of AGI is a formidable procedure with significant early mortality and morbidity. This treatment should be considered in the context of other revascularization options for management of an AGI.

Multicenter CT Image-Based Anatomic Assessment of Patients with Aortoiliac Aneurysm Undergoing Endovascular Repair with Iliac Branch Devices

BACKGROUND

The Global Iliac Branch Study (NCT05607277) is an international, multicenter, retrospective cohort study of anatomic predictors of adverse iliac events (AIEs) in aortoiliac aneurysms treated with iliac branch devices (IBDs).

METHODS

Patients with pre-IBD and post-IBD computed tomography imaging were included. We measured arterial diameters, stenosis, calcification, bifurcation angles, and tortuosity indices using a standardized, validated protocol. A composite of ipsilateral AIE was defined, a priori, as occlusion, type I or III endoleak, device constriction, or clinical event requiring reintervention. Paired t-test compared tortuosity indices and splay angles pretreatment and post-treatment for all IBDs and by device material (stainless steel and nitinol). Two-sample t-test compared anatomical changes from pretreatment to post-treatment by device material. Logistic regression assessed associations between AIE and anatomic measurements. Analysis was performed by IBD.

RESULTS

We analyzed 297 patients (286 males, 11 females) with 331 IBDs (227 stainless steel, 104 nitinol). Median clinical follow-up was 3.8 years. Iliac anatomy was significantly straightened with all IBD treatment, though stainless steel IBDs had a greater reduction in total iliac artery tortuosity index and aortic splay angle compared to nitinol IBDs (absolute reduction -0.20 [-0.22 to -0.18] vs. -0.09 [-0.12 to -0.06], P < 0.0001 and -19.6° [-22.4° to -16.9°] vs. -11.2° [-15.3° to -7.0°], P = 0.001, respectively). There were 54 AIEs in 44 IBDs in 42 patients (AIE in 13.3% of IBD systems), requiring 35 reinterventions (median time to event 41 days; median time to reintervention 153 days). There were 18 endoleaks, 29 occlusions, and 5 device constrictions. There were no strong associations between anatomic measurements and AIE overall, though internal iliac diameter was inversely associated with AIE in nitinol devices (nAIE, nitinol = 8).

CONCLUSIONS

Purpose-built IBDs effectively treat aortoiliac disease, including that with tortuous anatomy, with a high patency rate (91.5%) and low reintervention rate (9.1%) at 4 years. Anatomic predictors of AIE are limited.

Medical treatments for abdominal aortic aneurysm: an overview of clinical trials

INTRODUCTION

Abdominal aortic aneurysm is a progressive, segmental, abdominal aortic dilation associated with a high mortality rate. Abdominal aortic aneurysms with diameters larger than 55 mm are associated with a high risk of rupture, and the most effective treatment options are surgical repair. Close observation and lifestyle adjustments are recommended for smaller abdominal aortic aneurysms with lower rupture risk. The development of medical therapies that limit or prevent the progression, expansion, and eventual rupture of abdominal aortic aneurysms remains an unmet clinical need.

AREAS COVERED

This review provides an overview of completed and ongoing clinical trials examining the efficacies of various drug classes, including antibiotics, antihypertensive drugs, hypolipidemic drugs, hypoglycemic drugs, and other potential therapies for abdominal aortic aneurysms. A search of PubMed, Web of Science, Clinical Trials, and another six clinical trial registries was conducted in January 2024.

EXPERT OPINION

None of the drugs have enough evidence to indicate that they can effectively inhibit the dilation of abdominal aortic aneurysm. More clinical trial data is required to support the efficacy of propranolol. Future research should also explore different drug delivery mechanisms, such as nanoparticles, to elevate drug concentration at the aneurysm wall.

Urgent endovascular repair of juxtarenal/pararenal aneurysm by off-the-shelf multibranched endograft

OBJECTIVE

To report outcomes of urgent juxtarenal/pararenal aneurysms (J/P-AAAs) managed by off-the-shelf multibranched thoracoabdominal endografts (Cook, T-branch).

METHODS

In this observational, multicenter, retrospective study, patients with J/P-AAAs treated by urgent endovascular repair by T-branch in 23 European aortic centers, from 2013 to 2023, were analyzed. Contained J/P-AAAs rupture, presence of related symptoms, and aneurysm diameter of >70 mm were considered as indication for urgent repair. Technical success (TS), spinal cord ischemia (SCI), and 30-day/hospital mortality were assessed as early outcomes. Survival, freedom from reinterventions, and target artery instability (TAI) were evaluated during follow-up.

RESULTS

Overall, 197 patients (J-AAAs, n = 64 [33%]; P-AAAs, n = 95 [48%]; previous failed endovascular aneurysm repair (EVAR), n = 38 [19%]) were analyzed. The mean age and aneurysm diameter was 75 ± 8 years and 76 ± 4 mm, respectively. The American Society of Anesthesiologists score was 3 and 4 in 118 (60%) and 79 (40%) patients. Rupture, symptoms, and diameter of >70 mm were present in 51 (26%), 110 (56%), and 53 (27%) patients, respectively. An adjunctive proximal thoracic endograft was used in 28 cases (14%). The mean aortic coverage between the upper portion of the endograft and the lowest renal artery was 154 ± 49 mm. Single-stage repair and cerebrospinal fluid drainage were reported in 144 (73%) and 53 (27%) cases, respectively. TS was achieved in 182 (92%) cases (rupture, 84% vs no rupture, 95%; P = .02). Failures consist of TA loss (11 [6%]: renal artery, 9; celiac trunk, 2), type I to III endoleaks (2 [1%]), and 24-h mortality (2 [1%]). Rupture was a risk factor for technical failure (P = .02; odds ratio [OR], 3.8; 95% confidence interval [CI], 1.1-12.1). Overall, 15 patients (8%) had persistent SCI (rupture, 14% vs no rupture, 5%) with 11 (6%) , of paraplegia (rupture, 10% vs no rupture, 5%; P = .001). Rupture (P = .04; OR, 3.1; 95% CI, 1.1-8.9) and adjunctive proximal thoracic endograft (P = .01; OR, 4.1; 95% CI, 1.3-12.9) were risk-factors for SCI. Twenty-two patients (11%) died within 30 days or during a prolonged hospitalization. Previous failed EVAR (P = .04; OR, 3.6; 95% CI, 1.1-12.3), paraplegia (P < .001; OR, 9.9; 95% CI, 1.6-62.2) and postoperative mesenteric complications (P = .03; OR, 10.4; 95% CI, 1.2-93.3), as well as cardiac (P = .03; OR, 8.2; 95% CI, 2.0-33.0) and respiratory (P < .001; OR, 10.1; 95% CI, 2.9-35.2) morbidities were associated with 30-day/hospital mortality. The mean follow-up was 19 ± 5 months. The estimated 3-year survival and freedom from reinterventions was 58% and 77%, respectively. TAI occurred in 27 patients (14%) (occlusion, 15; endoleak, 14) with an estimated 3-year freedom from TAI of 72%.

CONCLUSIONS

Urgent repair of J/P-AAAs by T-branch is feasible and effective with satisfactory TS and 30-day/hospital mortality in high-risk patients. However, extensive aortic coverage is necessary, leading to a non-negligible SCI rate, especially in case of aortic rupture or when adjunctive thoracic endografts are necessary. Previous failed EVAR and postoperative mesenteric complications, as well as cardiac and respiratory morbidities were associated with 30-day/hospital mortality and should be subjected to more research for the purposes of improving outcomes.

Feasibility of a modified hybrid glubran-supported single-proglide technique for access closure during endovascular aneurysm repair

Objective

This study aimed to evaluate the feasibility of a hybrid Glubran-supported single-Proglide technique for large bore femoral access closure during percutaneous access endovascular aneurysm repair (EVAR).

Methods

A retrospective cohort study was performed for all percutaneous EVARs at our center from January 2023 to June 2023. All patients received the hybrid Glubran-supported single-Proglide technique involving a mixture of surgical glue and Lipiodol injection after single suture placement for femoral access closure. Technical success was defined as achieving complete hemostasis without a bailout strategy. Vascular complications and bleeding were defined by Valve Academic Research Consortium-3 (VARC-3) criteria. Vascular access changes and 30-day mortality were recorded.

Results

The technique success rate for the entire study population was 100% (55 femoral access in 37 patients; median age: 72; 78% males). The mean sheath size was 20.4 ± 2.3F. The mean manual compression time was 3.5 ± 1.4 min, the mean hemostasis time was 9.0 ± 2.5 min, and the mean procedural time was 103.9 ± 34.7 min. One patient (1.6%) developed an access site infection and recovered conservatively. No VARC-3 vascular complications and access changes were observed. No 30-day mortality happened.

Conclusions

The hybrid Glubran-supported single-Proglide technique is feasible for large bore access closure during EVAR and may be a viable alternative; however, larger prospective studies are required to confirm its efficacy.

Preoperative coronary interventions for preventing acute myocardial infarction in the perioperative period of major open vascular or endovascular surgery

BACKGROUND

Postoperative myocardial infarction (POMI) is associated with major surgeries and remains the leading cause of mortality and morbidity in people undergoing vascular surgery, with an incidence rate ranging from 5% to 20%. Preoperative coronary interventions, such as coronary artery bypass grafting (CABG) or percutaneous coronary interventions (PCI), may help prevent acute myocardial infarction in the perioperative period of major vascular surgery when used in addition to routine perioperative drugs (e.g. statins, angiotensin-converting enzyme inhibitors, and antiplatelet agents), CABG by creating new blood circulation routes that bypass the blockages in the coronary vessels, and PCI by opening up blocked blood vessels. There is currently uncertainty around the benefits and harms of preoperative coronary interventions.

OBJECTIVES

To assess the effects of preoperative coronary interventions for preventing acute myocardial infarction in the perioperative period of major open vascular or endovascular surgery.

SEARCH METHODS

We searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE Ovid, Embase Ovid, LILACS, and CINAHL EBSCO on 13 March 2023. We also searched the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) or quasi-RCTs that compared the use of preoperative coronary interventions plus usual care versus usual care for preventing acute myocardial infarction during major open vascular or endovascular surgery. We included participants of any sex or any age undergoing major open vascular surgery, major endovascular surgery, or hybrid vascular surgery.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes of interest were acute myocardial infarction, all-cause mortality, and adverse events resulting from preoperative coronary interventions. Our secondary outcomes were cardiovascular mortality, quality of life, vessel or graft secondary patency, and length of hospital stay. We reported perioperative and long-term outcomes (more than 30 days after intervention). We assessed the certainty of the evidence using the GRADE approach.

MAIN RESULTS

We included three RCTs (1144 participants). Participants were randomised to receive either preoperative coronary revascularisation with PCI or CABG plus usual care or only usual care before major vascular surgery. One trial enrolled participants if they had no apparent evidence of coronary artery disease. Another trial selected participants classified as high risk for coronary disease through preoperative clinical and laboratorial testing. We excluded one trial from the meta-analysis because participants from both the control and the intervention groups were eligible to undergo preoperative coronary revascularisation. We identified a high risk of performance bias in all included trials, with one trial displaying a high risk of other bias. However, the risk of bias was either low or unclear in other domains. We observed no difference between groups for perioperative acute myocardial infarction, but the evidence is very uncertain (risk ratio (RR) 0.28, 95% confidence interval (CI) 0.02 to 4.57; 2 trials, 888 participants; very low-certainty evidence). One trial showed a reduction in incidence of long-term (> 30 days) acute myocardial infarction in participants allocated to the preoperative coronary interventions plus usual care group, but the evidence was very uncertain (RR 0.09, 95% CI 0.03 to 0.28; 1 trial, 426 participants; very low-certainty evidence). There was little to no effect on all-cause mortality in the perioperative period when comparing the preoperative coronary intervention plus usual care group to usual care alone, but the evidence is very uncertain (RR 0.79, 95% CI 0.31 to 2.04; 2 trials, 888 participants; very low-certainty evidence). The evidence is very uncertain about the effect of preoperative coronary interventions on long-term (follow up: 2.7 to 6.2 years) all-cause mortality (RR 0.74, 95% CI 0.30 to 1.80; 2 trials, 888 participants; very low-certainty evidence). One study reported no adverse effects related to coronary angiography, whereas the other two studies reported five deaths due to revascularisations. There may be no effect on cardiovascular mortality when comparing preoperative coronary revascularisation plus usual care to usual care in the short term (RR 0.07, 95% CI 0.00 to 1.32; 1 trial, 426 participants; low-certainty evidence). Preoperative coronary interventions plus usual care in the short term may reduce length of hospital stay slightly when compared to usual care alone (mean difference -1.17 days, 95% CI -2.05 to -0.28; 1 trial, 462 participants; low-certainty evidence). We downgraded the certainty of the evidence due to concerns about risk of bias, imprecision, and inconsistency. None of the included trials reported on quality of life or vessel graft patency at either time point, and no study reported on adverse effects, cardiovascular mortality, or length of hospital stay at long-term follow-up.

AUTHORS' CONCLUSIONS

Preoperative coronary interventions plus usual care may have little or no effect on preventing perioperative acute myocardial infarction and reducing perioperative all-cause mortality compared to usual care, but the evidence is very uncertain. Similarly, limited, very low-certainty evidence shows that preoperative coronary interventions may have little or no effect on reducing long-term all-cause mortality. There is very low-certainty evidence that preoperative coronary interventions plus usual care may prevent long-term myocardial infarction, and low-certainty evidence that they may reduce length of hospital stay slightly, but not cardiovascular mortality in the short term, when compared to usual care alone. Adverse effects of preoperative coronary interventions were poorly reported in trials. Quality of life and vessel or graft patency were not reported. We downgraded the certainty of the evidence most frequently for high risk of bias, inconsistency, or imprecision. None of the analysed trials provided significant data on subgroups of patients who could potentially experience more substantial benefits from preoperative coronary intervention (e.g. altered ventricular ejection fraction). There is a need for evidence from larger and homogeneous RCTs to provide adequate statistical power to assess the role of preoperative coronary interventions for preventing acute myocardial infarction in the perioperative period of major open vascular or endovascular surgery.

LXRα Promotes Abdominal Aortic Aneurysm Formation Through UHRF1 Epigenetic Modification of miR-26b-3p

BACKGROUND

Abdominal aortic aneurysm (AAA) is a severe aortic disease without effective pharmacological approaches. The nuclear hormone receptor LXRα (liver X receptor α), encoded by the NR1H3 gene, serves as a critical transcriptional mediator linked to several vascular pathologies, but its role in AAA remains elusive.

METHODS

Through integrated analyses of human and murine AAA gene expression microarray data sets, we identified NR1H3 as a candidate gene regulating AAA formation. To investigate the role of LXRα in AAA formation, we used global Nr1h3-knockout and vascular smooth muscle cell-specific Nr1h3-knockout mice in 2 AAA mouse models induced with angiotensin II (1000 ng·kg·min; 28 days) or calcium chloride (CaCl2; 0.5 mol/L; 42 days).

RESULTS

Upregulated LXRα was observed in the aortas of patients with AAA and in angiotensin II- or CaCl2-treated mice. Global or vascular smooth muscle cell-specific Nr1h3 knockout inhibited AAA formation in 2 mouse models. Loss of LXRα function prevented extracellular matrix degeneration, inflammation, and vascular smooth muscle cell phenotypic switching. Uhrf1, an epigenetic master regulator, was identified as a direct target gene of LXRα by integrated analysis of transcriptome sequencing and chromatin immunoprecipitation sequencing. Susceptibility to AAA development was consistently enhanced by UHRF1 (ubiquitin-like containing PHD and RING finger domains 1) in both angiotensin II- and CaCl2-induced mouse models. We then determined the CpG methylation status and promoter accessibility of UHRF1-mediated genes using CUT&Tag (cleavage under targets and tagmentation), RRBS (reduced representation bisulfite sequencing), and ATAC-seq (assay for transposase-accessible chromatin with sequencing) in vascular smooth muscle cells, which revealed that the recruitment of UHRF1 to the promoter of miR-26b led to DNA hypermethylation accompanied by relatively closed chromatin states, and caused downregulation of miR-26b expression in AAA. Regarding clinical significance, we found that underexpression of miR-26b-3p correlated with high risk in patients with AAA. Maintaining miR-26b-3p expression prevented AAA progression and alleviated the overall pathological process.

CONCLUSIONS

Our study reveals a pivotal role of the LXRα/UHRF1/miR-26b-3p axis in AAA and provides potential biomarkers and therapeutic targets for AAA.

Friendly Neck Anatomy Does Not Prevent Neck-Related Adverse Events After EVAR

BACKGROUND

Life-long follow-up after endovascular aneurysm repair (EVAR) is costly and burdensome to the patient. Follow-up should be stratified based on the risk of EVAR failure. Aneurysm neck is thought to be the single most important risk factor. This study investigated neck anatomy as a predictor of neck-related adverse events after EVAR.

METHODS

This retrospective single-center study included consecutive patients undergoing elective EVAR for infrarenal abdominal aortic aneurysms between 2011 and 2016 (n = 222) who were followed with yearly imaging until December 2020. Hostile neck was defined as neck length ≤15 mm, width ≥28 mm, angulation ≥60°, calcification, or thrombus ≥50% of circumference or conical neck based on preoperative computed tomography angiography. Neck-related adverse event was defined as aneurysm rupture, any neck-related reintervention or type 1a endoleak during follow-up.

RESULTS

Ninety (41%) patients had hostile neck and 132 (59%) had friendly neck. There were no differences in 30-day mortality (1% vs. 1%, P = 0.78), major adverse events (20% vs. 16%, P = 0.43) or reinterventions during the hospital stay (8% vs. 4%, P = 0.20) between patients with hostile and friendly neck. Estimated survival at 1 year was 89 ± 3% for hostile neck and 95 ± 2% for friendly neck patients (P < 0.01). Five-year survival estimates were 51 ± 6% and 66 ± 4%, respectively. Aneurysm-related mortality was higher after 6 years in patients with hostile neck (P < 0.01). Twenty-four patients (11%) suffered neck-related adverse events with mean time-to-event of 3.3 ± 2.8 years; there were no differences between the groups stratified by neck anatomy. Incidentally, preoperative aneurysm diameter was found to be an independent risk factor for neck-related adverse events and aneurysm-related mortality; 53 patients (24%) had aneurysm diameter ≥70 mm, which was associated with nearly 4-fold risk of neck-related complications during the follow-up.

CONCLUSIONS

Friendly neck anatomy may not protect from neck-related adverse events after EVAR in the long-term. Especially patients with large aneurysms should be followed closely.

Long Term Outcomes of the Gore Excluder Low Permeability Endoprosthesis for the Treatment of Infrarenal Aortic Aneurysms

OBJECTIVE

This study evaluated the long term outcomes of endovascular aneurysm repair using the Gore Excluder Low Permeability (LP) endoprosthesis across high volume Dutch hospitals.

METHODS

A retrospective analysis was conducted of patients treated with the Excluder LP for infrarenal abdominal aortic aneurysm (AAA) in four hospitals between 2004 and 2017. Primary outcomes were overall survival, freedom from re-interventions (overall, inside and outside instructions for use, IFU), and AAA sac dynamics: growth (> 5 mm), stabilisation, and regression (< 5 mm). Secondary outcomes were technical success (device deployment), procedural parameters, and re-interventions. Follow up visits were extracted from patient files, with imaging assessed for complications and AAA diameter.

RESULTS

Five hundred and fourteen patients were enrolled, with a median (IQR) follow up of 5.0 (2.9, 6.9) years. Survival rates were 94.0% at one year, 73.0% at five years, and 37.0% at 10 years, with freedom from re-interventions of 89.0%, 79.0%, and 71.0%, respectively. 37.9% were treated outside IFU, leading to significantly more re-interventions over 10 years compared with those treated inside IFU (36.0% vs. 25.0%, respectively; p = .044). The aneurysm sac regressed by 53.5% at one year, 65.8% at five years, and 77.8% at 10 years, and grew by 9.8%, 14.3%, and 22.2%, respectively. Patients with one year sac growth had significantly worse survival (p = .047). Seven patients (1.4%) had a ruptured aneurysm during follow up. Over 15 years, type 1a endoleak occurred in 5.3%, type 1b in 3.1%, type 3 in 1.9%, type 4 in 0.2%, and type 2 in 35.6% of patients.

CONCLUSION

This multicentre study of real world endovascular aneurysm repair data using the Gore Excluder LP endoprosthesis demonstrated robust long term survival and re-intervention rates, despite 37.9% of patients being treated outside IFU, with type 4 endoleak being rare. Treatment outside IFU significantly increased re-intervention rates and one year sac growth was associated with statistically significantly worse survival.

Evaluating growth patterns of abdominal aortic aneurysms among women

OBJECTIVE

Though initially protected from vessel dilation by estrogen, women may experience rapid abdominal aortic aneurysm (AAA) growth post-menopause. The rate of growth has been poorly defined in prior literature. Here, we describe aneurysm growth in a cohort of women found through an AAA screening program.

METHODS

Women with AAAs were retrospectively identified. Aortic imaging was reviewed, and measurements of maximum transverse and anterior-posterior diameters were completed. Growth was stratified by the type of aortic pathology (fusiform aneurysm, aortic ectasia, dissection with aneurysmal degeneration, saccular aneurysm) as well as size category (<3 cm, 3.0-3.9 cm, 4.0-4.9 cm, ≥5.0 cm) at diagnosis.

RESULTS

A cohort of 488 women was identified; 286 had multiple scans for review. The mean age of the entire cohort was 75 ± 9.9 years. Stratified by type of pathology, the mean age was 76 ± 8.9 years in patients with a fusiform AAA, 74 ± 9.8 years in ectasia, 65 ± 13.7 years in dissection, and 76 ± 5.6 years in saccular aneurysms. The maximum growth was highest in women with fusiform AAAs, followed by dissection, ectasia, and saccular pathology (9.7 mm, 7.0 mm, 3.0 mm, and 2.2 mm, respectively; P < .001). Comparing mean growth by year, the highest mean growth was in fusiform AAAs (3.6 mm vs 1.75 mm in dissection; P < .001). The Shapiro-Wilk test demonstrated that mean growth per year was non-normally distributed with a right skew. Stratified by aortic diameter at the time of diagnosis, mean growth/year increased with increasing size at diagnosis in fusiform AAAs and dissection (0.91 mm for <3 cm, 2.34 mm for 3.0-3.9 cm, 2.49 mm for 4.0-4.9 mm, and 6.16 mm for ≥5.0 cm in patients with fusiform AAAs vs 0.57 mm, 0.94 mm, 1.87 mm, and 2.66 mm, respectively, for patients with dissection). Smoking history was associated with a higher mean growth/year (2.6 mm vs 3.3 mm; P < .001). Conversely, patients with a family history of AAA had a lower mean growth/year (3.2 mm vs 1.5 mm; P < .001).

CONCLUSIONS

The rate of aneurysm growth in women varies based on pathology and aneurysm size, and women experience rapid aneurysm growth at sizes greater than 4.5 cm. Current screening guidelines are inadequate, and our results demonstrate that the rate of growth of fusiform aneurysms in women is faster than in men at a smaller size and may warrant more frequent surveillance than current Society for Vascular Surgery recommendations to prevent risk of increased morbidity.