National trends in open surgical, endovascular, and branched-fenestrated endovascular aortic aneurysm repair in Medicare patients

Intraoperative Staff Radiation Exposure During Aortic Endovascular Procedures

BACKGROUND

The risk of radiation exposure in the surgical operating room (OR) and/or catheterization laboratory is now well established. Complex endovascular procedures often require multiple approaches and different positioning of the staff members around the patient, potentially increasing the levels of radiations exposure. Our goal was to evaluate the levels of radiation exposure of the members of the staff during endovascular aortic procedures in order to propose radioprotection optimization.

METHODS

We included 41 aortic endovascular procedures out of 114 procedures performed between January 12, 2014, and August 31, 2015, including 24 standard endovascular aortic aneurysm repair (EVAR), 7 EVAR with iliac branch (EVARib), 8 complex fenestrated/branched EVAR (F/B EVAR), and 2 thoracic EVAR (TEVAR). Procedures were performed in an OR equipped with a carbon fiber table and a mobile fluoroscopy C-arm. We collected the usual dosimetry data given by the C-arm as well as the patient's peak skin dose (PSD). In all staff members, radiation exposure was measured with thermoluminescent chip dosimeters placed on both temples, on posterior sides of both hands, and on both lower legs.

RESULTS

PSD levels were low for EVAR because 24 patients had values below the reading threshold. PSD significantly increased with more complex procedures. Main operator (MO) received the higher level of irradiation on whole body, hands, and ankles. Eye lenses irradiation was higher on both assistant operators (AOs). Other members received low levels of irradiation. We found a high ranges of radiation exposure with a high risk of exposure for the AO, mainly for F/B EVAR and EVARib.

CONCLUSIONS

Even if all personal protections are used, staff positioning is a major point that must be considered. If MO is supposed to be the most exposed to X-rays, specific conditions of positioning of the AO may be at risk of exposure.

Hospital-level variation in costs of elective nonruptured abdominal aortic aneurysm repair

BACKGROUND

With the aging population in the United States, the incidence of abdominal aortic aneurysms is shifting to older ages. Given changing demographic characteristics and increasing health care expenditures, the present study evaluated the degree of center-level variation in the cost of elective abdominal aortic aneurysm repair.

METHODS

We identified all adult (≥18 years) hospitalizations for elective repair of nonruptured abdominal aortic aneurysms in the 2017 to 2020 Nationwide Readmissions Database. Hierarchical mixed-effects models were used to rank hospitals based on risk-adjusted costs. The interclass coefficient was used to calculate the amount of variation attributable to hospital-level characteristics. High-cost hospitals were classified as centers in the top decile of costs. The association of high-cost hospitals status with outcomes of interest was examined.

RESULTS

An estimated 62,626 patients underwent abdominal aortic aneurysm repair, and 5,011 (8.0%) were managed at high-cost hospitals. Compared with non-high-cost hospitals, high-cost hospitals were more commonly large (52.6% vs 48.3%) metropolitan (78.3% vs 66.9%) teaching centers (all P < .001). The interclass coefficient found that 28% of the observed variation in cost is attributable to hospital factors. After adjustment, high-cost hospitals were associated with increased odds of gastrointestinal (adjusted odds ratio = 1.42; 95% CI, 1.05-1.90) and infectious (adjusted odds ratio = 1.35; 95% CI, 1.14-1.59) complications. Finally, the Elixhauser index (β = +$2,700/unit; 95% CI, $2,500-$3,000) and open repair (β = +$4,100; 95% CI, $3,100-$5,200) were associated with increased costs.

CONCLUSION

We observed significant variation in cost attributable to center-level differences. Our findings have implications for reimbursement paradigms and the establishment of quality and cost benchmarks in the elective repair of abdominal aortic aneurysm.

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.

Feasibility and Cost Analysis of Ambulatory Endovascular Aneurysm Repair

PURPOSE

We sought to compare the costs of ambulatory endovascular aneurysm repair (a-EVAR) and inpatient EVAR (i-EVAR) at up to 1-year of follow-up.

MATERIALS AND METHODS

A retrospective cohort study of consecutive patients undergoing elective EVAR between April 2016 and December 2018 at two academic centers. Patients planned for a-EVAR were compared with i-EVAR. Costs at 30 days and 1 year were extracted. These included operating room (OR) use, bed occupancy, laboratory and imaging, emergency department (ED) visits, readmissions, and reinterventions. Baseline characteristics were compared. Multiple regression model was used to identify predictors of increased EVAR costs. Repeated measures analysis of variance (ANOVA) was used to compare cost differences at 30 days and 1 year via an intention-to-treat analysis. Bonferroni post hoc test compared between-group differences. A p value<0.05 was considered statistically significant.

RESULTS

One hundred seventy patients were included. Most underwent percutaneous EVAR (>94%) under spinal anesthesia (>84%). Ambulatory endovascular aneurysm repair was successful in 84% (84/100). Ambulatory endovascular aneurysm repair patients (76±8 years) were younger than i-EVAR (78±9 years). They also had a smaller mean aneurysm diameter (56±6 mm) compared with i-EVAR (59±6 mm). Emergency department visits, readmissions, and reinterventions were similar up to 1 year (all p=NS). Ambulatory endovascular aneurysm repair costs showed a non-statistically significant reduction in total costs at 30 days and 1 year by 27% and 21%, respectively. Patients younger than 85 years and males had a 30-day cost reduction by 34% (p=0.027) and 33% (p=0.035), respectively with a-EVAR.

CONCLUSIONS

Same-day discharge is feasible and successful in selected patients. Patients younger than 85 years and males have a short-term cost benefit with EVAR done in the ambulatory setting without increased complications or reinterventions.

CLINICAL IMPACT

This study shows the overall safety of ambulatory EVAR with proper patient selection. These patient had similar post-intervention complications to inpatients. Same day discharge also resulted in short-term reduction in costs in male patients and patients younger than 85 years.

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.

Adoption and clinical outcomes of fenestrated endovascular aneurysm repair in a regional, multistate community hospital system

OBJECTIVE

Complex endovascular abdominal aortic aneurysm (AAA) repair techniques have evolved over the last decade, yet patterns of physician and hospital system adoption of fenestrated endovascular aneurysm repair (FEVAR) remain poorly defined. We investigated clinical outcomes, use trends, and surgeon and hospital experience for FEVAR in a large community hospital system.

METHODS

We conducted a retrospective cohort study of all FEVAR procedures within our 5-state hospital system between April 2012 and June 2021. AAA repair volumes (open, EVAR, and FEVAR) were captured at the hospital and surgeon levels using Current Procedural Terminology and International Classification of Diseases codes. Clinical and outcomes data were collected for FEVAR patients. To consider if surgeon or hospital experience influenced outcomes, sequential case number was used to divide patients into surgeon experience and hospital experience groups. Inverse probability weighted and generalized linear mixed models, adjusted for demographics and comorbidities, were built to examine risk-adjusted outcomes for surgeon and hospital experience groups.

RESULTS

Of 3850 patients treated with AAA procedures of any kind between 2012 and 2021, 160 (4.2%) underwent FEVAR. FEVAR procedures were performed by 34 different surgeons at 12 hospitals, with intraoperative complications and unplanned adjunctive procedures occurring in 18.8% (n = 30) and 19.4% (n = 31) of patients, respectively. Among FEVAR patients, in-hospital mortality was 1.3% (n = 2) and postoperative morbidity was 16.9% (n = 27). Renal function decline occurred postoperatively in 5.1% of patients. Early (<30 day) postoperative endoleaks occurred in 15.3% of patients (n = 21). Target vessel patency was 95.6% on initial postoperative imaging. Surgeon and hospital experience had a small positive impact on outcomes after the first one to three cases. Significant decreases in operative time, fluoroscopy time, and estimated blood loss were observed with increased surgeon experience, relative to a surgeon's first case (P < .05). There were lower odds of intraoperative complications after a surgeon's first case (odds ratio [OR], 0.16; 95% confidence interval [CI], 0.03-0.77, for cases 2-3) or after a hospital's first one to three cases (OR, 0.19; 95% CI, 0.04-0.89, for cases 4-8; OR, 0.12; 95% CI, 0.03-0.55 for cases 9-49).

CONCLUSIONS

Clinical outcomes of FEVAR across our hospital system compare favorably with previously published reports. Although system-wide FEVAR adoption increased 3-fold over the last decade, FEVAR continued to be performed by a minority of hospitals in our system. The results from this cohort demonstrate low rates of adverse events, high rates of technical efficiency, and a small impact of surgeon and hospital experience, thereby supporting this advanced endovascular technology as a safe, efficacious, and generalizable treatment alternative to open repair for patients with complex aortic anatomy.

Follow-up compliance in patients undergoing abdominal aortic aneurysm repair at Veterans Affairs hospitals

OBJECTIVE

The Society for Vascular Surgery guidelines recommend annual imaging surveillance following endovascular aneurysm repair (EVAR) and every 5 years following open surgical repairs (OSR) of abdominal aortic aneurysms (AAAs). Adherence to these guidelines is low outside of clinical trials, and compliance at Veterans Affairs (VA) hospitals is not yet well-established. We examined imaging follow-up compliance and mortality rates after AAA repair at VA hospitals.

METHODS

We queried the VA Surgical Quality Improvement Program database for elective infrarenal AAA repairs, EVAR and OSR, then merged in follow-up imaging and mortality information. Mortality rate over time was derived using Kaplan-Meier estimation. Generalized estimating equation with a logit link and a sandwich standard error estimate was performed to compare the probability of having annual follow-up imaging over time between procedure types and to identify variables associated with follow-up imaging for EVAR patients.

RESULTS

Our analysis included 11,668 patients who underwent EVAR and 4507 patients who underwent OSR at VA hospitals between the years 2000 and 2019. The 30-day mortality rate for EVAR and OSR was 0.37% and 0.82%, respectively. OSR was associated with lower long-term mortality after adjusting age, sex, American Society of Anesthesiologists classification and preoperative renal failure with an adjusted hazard ratio of 0.88 (95% confidence interval, 0.84-0.92; P < .01). Of surviving patients, the follow-up imaging rate was 69.1% by 1 year post-EVAR. The follow-up rate after 5 years was 45.6% post-EVAR compared with 63.6% post-OSR of surviving patients. A history of smoking or drinking, baseline hypertension, and known cardiac disease were independently associated with poor follow-up after EVAR.

CONCLUSIONS

Patients undergoing elective open AAA repair in the VA hospital system had lower long-term mortality compared with patients who underwent endovascular repair. Compliance with post-EVAR imaging is low. Patient factors associated with poor post-EVAR imaging surveillance were smoking within the last year, excess alcohol consumption, and cardiac risk factors including hypertension, prior myocardial infarction, and congestive heart failure.

Preoperative risk score for mortality within 3 years of visceral segment fenestrated endovascular aortic repair

OBJECTIVE

The purpose of this study was to create a risk score for the event of mortality within 3 years of complex fenestrated visceral segment endovascular aortic repair utilizing variables existing at the time of preoperative presentation.

METHODS

After exclusions, 1916 patients were identified in the Vascular Quality Initiative who were included in the analysis. The first step in development of the risk score was univariable analysis for the primary outcome of mortality within 3 years of surgery. χ2 analysis was performed for categorical variables, and comparison of means with independent Student t-test was performed for ordinal variables. Variables that achieved a univariable P value less than 0.1 were then placed into Cox regression multivariable time dependent analysis for the development of mortality within 3 years. Variables that achieved a multivariable significance of less than 0.1 were utilized for the risk score, with point weighting based on the beta-coefficient. Variables with a beta coefficient of 0.25 to 0.49 were assigned 1 point, 0.5 to 0.74 2 points, 0.75 to 0.99 3 points, and 1.0 to 1.25 4 points. A cumulative score for each patient was then summed, the percentage of patients at each score experiencing mortality within 3 weeks was then calculated, and a comparison of score outcomes was conducted with binary logistic regression. Area under the curve analysis was performed.

RESULTS

The primary outcome of mortality within 3 years of surgery occurred in 12.8% of patients (245/1916). The mean age for the study population was 73.35 years (standard deviation [SD], 8.26 years). The mean maximal abdominal aortic aneurysm (AAA) diameter was 60.43 mm (SD, 10.52 mm). The mean number of visceral vessels stented was 3.3 (SD, 0.76). Variables present at the time of surgery that were included in the risk score were: hemodialysis (3 points); age >87, chronic obstructive pulmonary disease, hypertension, AAA diameter >77 mm (all 2 points); and body mass index <20 kg/m2, female sex, congestive heart failure, active smoking, chronic renal insufficiency, age 80 to 87 years, and AAA diameter 67 to 77 mm (all 1 point). BMI >30 kg/m2 (mean, 34.46 kg/m2) and age <67 years were protective (-1 point). Testing the model resulted in an area under the curve of 0.706. Hosmer and Lemeshow goodness of fit test for logistic regression utilizing the 15 different risk score total groups revealed a model predictive accuracy of 87.3%. Significant escalations in 3-year mortality were noted to occur at scores of 6 and greater. Mean AAA diameter was significantly larger for patients who had higher risk scores (P < .001).

CONCLUSIONS

A novel risk score for mortality within 3 years of fenestrated visceral segment aortic endograft has been developed that has excellent accuracy in predicting which patients will survive and derive the strongest benefit from intervention. This facilitates risk-benefit analysis and counseling of patients and families with realistic long-term expectations. This potentially enhances patient-centered decision-making.

Duplex Ultrasound-Only Surveillance after Endovascular Abdominal Aortic Aneurysm Repair is Associated with Favorable Long-Term Outcomes

BACKGROUND

Long-term data surrounding the impact of different endovascular abdominal aortic aneurysm repair (EVAR) surveillance strategies are limited. Therefore, the purpose of this study was to characterize postoperative imaging patterns, as well as to evaluate the association of duplex ultrasound surveillance after the first postoperative year with 5-year EVAR outcomes.

METHODS

EVAR patients (2003-2016), who survived at least 1 year without aneurysm rupture, conversion to open repair, and reintervention in the Vascular Implant Surveillance and Interventional Outcomes Network were examined to provide all subjects ≥3 years of follow-up time. Patients were categorized into 6 cohorts after the first postoperative year: No imaging (N = 953); computed tomography (CT)/magnetic resonance imaging (MRI)-only (N = 2,976); duplex ultrasound-only (DUS; N = 1,808); combined CT/MRI + DUS with >50% being CT/MRI (N = 1,937); combined CT/MRI + DUS with >50% being DUS (N = 2,253); and mixed (CT + DUS + MRI N = 1,272). Abdominal aortic aneurysm (AAA)-related reintervention, rupture, conversion to open repair, and all-cause mortality were estimated using Kaplan-Meier analysis. Multivariable logistic regression models identified variables associated with using DUS-only imaging (versus CT/MRI only). Cox regression models compared 5-year outcomes between patients receiving DUS-only versus CT/MRI-only imaging.

RESULTS

A total of 11,199 EVAR patients were examined (mean age 76 ± 7 years; female: 20%; nonelective: 10%). DUS-only imaging surveillance after the first postoperative year was more likely to occur after elective repairs, as well as among older, male patients. Smaller (<6 cm) preoperative AAA diameter and absence of documented concurrent iliac aneurysm was also associated with DUS-only follow-up. Additionally, no endoleak detection on index EVAR completion imaging, as well as a documented >5 mm decrease in AAA sac diameter at 1-year follow-up was more common with DUS-only surveillance protocols. Post-EVAR DUS-only imaging after the first postoperative year had the lowest incidence of reintervention, conversion to open repair, and rupture (as well as the composite reintervention/open conversion/rupture; log-rank P < 0.001 for all). Further, patients receiving exclusively DUS after their first postoperative year had better overall survival (log-rank P < 0.001). These outcome advantages that were associated with DUS-only surveillance compared with CT/MRI-only surveillance after EVAR persisted when controlling for baseline covariates, preoperative AAA diameter, prior aortic surgery history, sac growth, and presence of endoleak (all P < 0.01).

CONCLUSIONS

EVAR patients selected for DUS-only surveillance after the first postoperative year have excellent freedom from AAA-related reintervention, conversion to open repair, rupture and all-cause mortality. These findings remained on multivariable analysis after adjusting for baseline characteristics, endoleak status and sac diameter changes within the first year. This is the first registry-based investigation to document long-term EVAR outcomes for patients entered into a DUS-only monitoring protocol which serves to corroborate the growing evidence base that DUS may be able to supplant CT surveillance in certain subgroups. A prospective randomized multicenter trial comparing DUS versus CT-based imaging after EVAR is needed to validate these findings which may serve to change current practice guidelines, as well as industry and regulatory stakeholder requirements.

The rise of endovascular repair for abdominal, thoracoabdominal, and thoracic aortic aneurysms

BACKGROUND

Given changes in intervention guidelines and the growing popularity of endovascular treatment for aortic aneurysms, we examined the trends in admissions and repairs of abdominal aortic aneurysms (AAAs), thoracoabdominal aortic aneurysms (TAAAs), and thoracic aortic aneurysms (TAAs).

METHODS

We identified all patients admitted with ruptured aortic aneurysms and intact aortic aneurysms repaired in the Nationwide Inpatient Sample between 2004 and 2019. We then examined the use of open, endovascular, and complex endovascular repair (OAR, EVAR, and cEVAR) for each aortic aneurysm location (AAA, TAAA, and TAA), alongside their resulting in-hospital mortality, over time. cEVAR included branched, fenestrated, and physician-modified endografts.

RESULTS

715,570 patients were identified with AAA (87% intact repairs and 13% rupture admissions). Both intact AAA repairs and ruptured AAA admissions decreased significantly between 2004 and 2019 (intact 41,060-34,215, P < .01; ruptured 7175-4625, P = .02). Of all AAA repairs performed in a given year, the use of EVAR increased (2004-2019: intact 45%-66%, P < .01; ruptured 10%-55%, P < .01) as well as cEVAR (2010-2019: intact 0%-23%, P < .01; ruptured 0%-14%, P < .01). Mortality after EVAR of intact AAAs decreased significantly by 29% (2004-2019, 0.73%-0.52%, P < .01), whereas mortality after OAR increased significantly by 16% (2004-2019, 4.4%-5.1%, P < .01). In the study, 27,443 patients were identified with TAAA (80% intact and 20% ruptured). In the same period, intact TAAA repairs trended upward (2004-2019, 1435-1640, P = .055), and cEVAR became the most common approach (2004-2019, 3.8%-72%, P = .055). A total of 141,651 patients were identified with ascending, arch, or descending TAAs (90% intact and 10% ruptured). Intact TAA repairs increased significantly (2004-2019, 4380-10,855, P < .01). From 2017 to 2019, the mortality after OAR of descending TAAs increased and mortality after thoracic endovascular aneurysm repair decreased (2017-2019, OAR 1.6%-3.1%; thoracic endovascular aneurysm repair 5.2%-3.8%).

CONCLUSIONS

Both intact AAA repairs and ruptured AAA admissions significantly decreased between 2004 and 2019. The use of endovascular techniques for the repair of all aortic aneurysm locations, both intact and ruptured, increased over the past two decades. Most recently in 2019, 89% of intact AAA repairs, infrarenal through suprarenal, were endovascular (EVAR or cEVAR, respectively). cEVAR alone increased to 23% of intact AAA repairs in 2019, from 0% a decade earlier. In this period of innovation, with many new options to repair aortic aneurysms while maintaining arterial branches, endovascular repair is now used for the majority of all intact aortic aneurysm repairs. Long-term data are needed to evaluate the durability of these procedures.

Unsupervised machine learning cluster analysis to identification EVAR patients clinical phenotypes based on radiomics

OBJECTIVE

This study used unsupervised machine learning (UML) cluster analysis to explore clinical phenotypes of endovascular aortic repair (EVAR) for abdominal aortic aneurysm (AAA) patients based on radiomics.

METHOD

We retrospectively reviewed 1785 patients with infra-renal AAA who underwent elective EVAR procedures between January 2010 and December 2020. Pyradiomics was used to extract the radiomics features. Statistical analysis was applied to determine the radiomics features that related to severe adverse events (SAEs) after EVAR. The selected features were used for UML cluster analysis in training set and validation in test set. Comparison of basic characteristics and radiomics features of different clusters. The Kaplan-Meier analysis was conducted to generate the cumulative incidence of freedom from SAEs rate.

RESULT

A total of 1180 patients were enrolled. During the follow-up, 353 patients experienced EVAR-related SAEs. In total, 1223 radiomics features were extracted from each patient, of which 23 radiomics features were finally preserved to identify different clinical phenotypes. 944 patients were allocated to the training set. Three clusters were identified in training set, in which patients had identical clinical characteristics and morphological features, while varied considerably of selected radiomics features. This encouraging performance was further approved in the test set. In addition, each cluster was well differentiated from other clusters and Kaplan-Meier analysis showed significant differences of freedom from SAEs rate between different clusters both in the training (p = .0216) and test sets (p = .0253).

CONCLUSION

Based on radiomics, UML cluster analysis can identify clinical phenotypes in EVAR patients with distinct long-term outcomes.

Impact of the endovascular revolution on vascular training through analysis of national data case reports

BACKGROUND

In the last couple of decades, there has been a shift in use of endovascular procedures in vascular surgery. We aim to examine the impact of this endovascular shift on vascular trainees, determine whether the surgical experiences of trainees in the integrated residency and fellowship program changed over time, and identify differences between the two training paradigms.

METHODS

Data were extracted from the Accreditation Council for Graduate Medical Education National Data Case Logs for the vascular surgery fellowship (1999-2021) and integrated residency (2012-2021) programs. Every procedure was categorized as open or endovascular, then designated into the following subcategories: thoracic aneurysm repairs, cerebrovascular, abdominal aneurysm repairs, venous, vascular access, peripheral arterial disease, visceral, or miscellaneous. We compared the prevalence of open and endovascular cases in the fellowship and integrated residency using data from overlapping years (2012-2021). In addition, we compared the mean number of cases per trainee per year within designated time intervals. The vascular surgery fellowship was grouped into three intervals: 1999 to 2006, 2006 to 2013, and 2013 to 2021; the integrated vascular surgery residency was grouped into two intervals: 2012 to 2017 and 2017 to 2021. Data were standardized to represent the average number of cases per trainee per year.

RESULTS

Within the fellowship, we found a 362.37% increase in endovascular procedures (mean, 56.80 ± 32.57 vs 262.63 ± 9.91; P < .001), although there was only a 32.47% increase in open procedures (220.19 ± 4.55 vs 291.68 ± 8.20) between the first and last time intervals. There was a decrease in abdominal aneurysm repair (24.46 ± 7.30 vs 13.85 ± 0.58; P < .001) and visceral (6.41 ± 0.44 vs 5.80 ± 0.42; P = .039) open procedures. For the integrated residency, there was an increase in open procedures by 8.52% (352.18 ± 8.23 vs 382.20 ± 5.84; P < .001). Residents had greater total, open, and endovascular procedures per year than fellows (all P < .001). Chief residents had approximately one-half as many cases as vascular fellows per year. Fellows performed more open abdominal aneurysm repair (14.04 ± 0.80 vs 12.40 ± 1.32; P = .007) and visceral (5.83 ± 0.41 vs 4.88 ± 0.46; P > .001) procedures than residents. Overall, 52% to 53% of cases performed by trainees per year were open procedures in both the fellowship and integrated residency (288.56 ± 12.10 vs 261.27 ± 10.13, 365.52 ± 17.23 vs 319.58 ± 6.62; both P < .001). Within the subcategories, only cerebrovascular, vascular access, and miscellaneous had more open procedures performed per trainee.

CONCLUSIONS

Vascular surgery training has incorporated new endovascular techniques and technologies while maintaining operative training in open procedures. Despite changes in vascular surgery training, trainees are still performing more open procedures than endovascular procedures per year. However, there are evolving deficits in specific types of procedures.

Vascular Anastomoses and Dissection: A Six-Part Simulation Curriculum for Surgical Residents

Introduction

As surgical technologies grow, so too do demands on surgical trainees to master increasing numbers of skill sets. With the rise of endovascular surgery, trainees have fewer opportunities to practice open vascular techniques in the operating room. Simulation can bridge this gap. However, existing published open vascular simulation curricula are basic or based on expensive models.

Methods

We iteratively developed an open vascular skills curriculum for second-year surgery residents comprising six 2-hour sessions. We refined the curriculum based on feedback from learners and faculty. The curriculum required skilled facilitators, vascular instruments, and tissue models. We evaluated the latest iteration with a survey and by assessing participants' technical skills using the Objective Structured Assessment of Technical Skills (OSATS) form.

Results

Over the past 10 years, 101 residents have participated in the curriculum. Nine of 13 residents who participated in the latest curricular iteration completed the survey. All respondents rated the sessions as excellent and strongly agreed that they had improved their abilities to perform anastomoses with tissue and prosthetic. Facilitators completed 18 OSATS forms for residents in the fifth and sixth sessions of the latest iteration. Residents scored well overall, with a median 26.5 (interquartile range: 24-29) out of a possible score of 35, with highest scores on knowledge of instruments.

Discussion

This simulation-based curriculum facilitates open vascular surgical skill acquisition among surgery residents. The curriculum allows residents to acquire critical vascular skills that are challenging to learn in an increasingly demanding operative setting.

A national census for the off-label treatment of complex aortic aneurysms

OBJECTIVE

Despite regulatory challenges, device availability, and rapidly expanding techniques, off-label endovascular repair of complex aortic aneurysms (cAAs) has expanded in the past decade. Given the lack of United States Food and Drug Administration-approved endovascular technology to treat cAAs, we performed a national census to better understand volume and current practice patterns in the United States.

METHODS

Targeted sampling identified vascular surgeons with experience in off-label endovascular repair of cAAs. An electronic survey was distributed with institutional review board approval from the University of Rochester to 261 individuals with a response rate of 38% (n = 98).

RESULTS

A total of 93 respondents (95%) reported off-label endovascular repair of cAAs. Mean age was 45.7 ± 8.3 years, and 84% were male. Most respondents (59%) were within the first 10 years of practice, and 69% trained at institutions with a high-volume of off-label endovascular procedures for complex aortic aneurysms with or without a physician-sponsored investigational device exemption (PS-IDE). Twelve respondents from 11 institutions reported institutional PS-IDEs for physician-modified endografts (PMEGs), in-situ laser fenestration (ISLF), or parallel grafting technique (PGT), including sites with PS-IDEs for custom-manufactured devices. Eighty-nine unique institutions reported elective off-label endovascular repair with a mean of 20.2 ± 16.5 cases/year and ∼1757 total cases/year nationally. Eighty reported urgent/emergent off-label endovascular repair with a mean of 5.7 ± 5.4 cases/year and ∼499 total cases/year nationally. There was no correlation between high-volume endovascular institutions (>15 cases/year) and institutions with high volumes of open surgical repair for cAAs (>15 cases/year; odds ratio, 0.7; 95% confidence interval, 0.3-1.5; P = .34). Elective techniques included PMEG (70%), ISLF (30%), hybrid PMEG/ISLF (18%), and PGT (14%), with PMEG being the preferred technique for 63% of respondents. Techniques for emergent endovascular treatment of complex aortic disease included PMEG (52%), ISLF (40%), PGT (20%), and hybrid-PMEG/ISLF (14%), with PMEG being the preferred technique for 41% of respondents. Thirty-nine percent of respondents always or frequently offer referrals to institutions with PS-IDEs for custom-manufactured devices. The most common barrier for referral to PS-IDE centers included geographic distance (48%), longitudinal relationship with patient (45%), and costs associated with travel (33%). Only 61% of respondents participate in the Vascular Quality Initiative for complex endovascular aneurysm repair, and only 57% maintain a prospective institutional database. Eighty-six percent reported interest in a national collaborative database for off-label endovascular repair of cAA.

CONCLUSIONS

Estimates of off-label endovascular repair of cAAs are likely underrepresented in the literature based on this national census. PMEG was the most common technique for elective and emergent procedures. Under-reported off-label endovascular repair of cAA outcomes data appears to be limited by non-standardized PS-IDE reporting to the United States Food and Drug Administration, and the lack of Vascular Quality Initiative participation and prospective institutional data collection. Most participants are interested in a national collaborative database for endovascular repair of cAAs.

Practice patterns of antiplatelet and anticoagulant therapy after fenestrated/branched endovascular aortic repair

OBJECTIVE

Antiplatelet and/or anticoagulant therapy are commonly prescribed after fenestrated/branched endovascular aortic repair (F/BEVAR). However, the optimal regimen remains unknown. We sought to characterize practice patterns and outcomes of antiplatelet and anticoagulant use in patients who underwent F/BEVAR.

METHODS

Consecutive patients enrolled (2012-2023) as part of the United States Aortic Research Consortium (US-ARC) from 10 independent physician-sponsored investigational device exemption studies were evaluated. The cohort was characterized by medication regimen on discharge from index F/BEVAR: (1) Aspirin alone OR P2Y12 alone (single-antiplatelet therapy [SAPT]); (2) Anticoagulant alone; (3) Aspirin + P2Y12 (dual-antiplatelet therapy [DAPT]); (4) Aspirin + anticoagulant OR P2Y12 + anticoagulant (SAPT + anticoagulant); (5) Aspirin + P2Y12 + anticoagulant (triple therapy [TT]); and (6) No therapy. Kaplan-Meier analysis and Cox proportional hazards modeling were used to compare 1-year outcomes including survival, target artery patency, freedom from bleeding complication, freedom from all reinterventions, and freedom from stent-specific reintervention.

RESULTS

Of the 1525 patients with complete exposure and outcome data, 49.6% were discharged on DAPT, 28.8% on SAPT, 13.6% on SAPT + anticoagulant, 3.2% on TT, 2.6% on anticoagulant alone, and 2.2% on no therapy. Discharge medication regimen was not associated with differences in 1-year survival, bleeding complications, composite reintervention rate, or stent-specific reintervention rate. However, there was a significant difference in 1-year target artery patency. On multivariable analysis comparing with SAPT, DAPT conferred a lower hazard of loss of target artery patency (hazard ratio [HR], 0.48; 95% confidence interval [CI], 0.27-0.84; P = .01). On sub-analyses of renal stents alone or visceral stents alone, DAPT no longer had a significantly lower hazard of loss of target artery patency (renal: HR, 0.66; 95% CI, 0.35-1.27; P = .22; visceral: HR, 0.31; 95% CI, 0.05-1.9; P = .21). Lastly, duration of DAPT therapy (1 month, 6 months, or 1 year) did not significantly affect target artery patency.

CONCLUSIONS

Practice patterns for antiplatelet and anticoagulant regimens after F/BEVAR vary widely across the US-ARC. There were no differences in bleeding complications, survival or reintervention rates among different regimens, but higher branch vessel patency was noted in the DAPT cohort. These data suggest there is a benefit in DAPT therapy. However, the generalizability of this finding is limited by the retrospective nature of this data, and the clinical significance of this finding is unclear, as there is no difference in survival, bleeding, or reintervention rates amongst the different regimens. Hence, an "optimal" regimen, including the duration of such regimen, could not be clearly discerned. This suggests equipoise for a randomized trial, nested within this cohort, to identify the most effective antiplatelet/anticoagulant regimen for the growing number of patients being treated globally with F/BEVAR.

Serious Failure Modes After EVAR Are Device Specific

OBJECTIVES

Type I and III endoleaks following endovascular aneurysm repair (EVAR) can lead to catastrophic events that require major re-interventions. We reviewed our experience with aortic endograft re-interventions for type I and III endoleaks and other serious failures among different devices.

METHODS

We retrospectively reviewed patients with a prior EVAR who underwent open conversion (OC) or major endovascular intervention (MEI) (re-lining, cuff/limb extension, parallel graft) for type I/III endoleaks at our institution from 2002 to 2019. Baseline characteristics, procedural details, re-interventions, and outcomes were collected.

RESULTS

A total of 229 patients (194 men) underwent re-interventions for type I and III endoleaks after EVAR (90 OC, 139 MEI) for devices implanted between 1997 and 2019. Average age at re-intervention was 78±8.5 years. A total of 135 (59%) were implanted at our institution, whereas 93 (41%) were referred. Median time to re-intervention was 4 years with 25% to 75% interquartile range (IQR) of 2.2-6.6 years. There was no significant difference in baseline demographics or type of re-interventions (OC/MEI) between device types. 42/229 (18%) presented with ruptured aneurysms, 20/229 (9%) were symptomatic, whereas the rest presented with asymptomatic radiographic findings. Type 1A endoleak was present in 146/229 (63.8%-72 with proximal migration), type IB in 46/229 (20.1%), type IIIA in 37/229 (16.6%), type IIIB in 15/229 (6.5%), and persistent aneurysm sac growth with no radiographic evidence of an endoleak in 6/229 (2.6%). Devices included most commercial products: AFX, Excluder, AneuRx, Ancure, Endurant, and Zenith. A smaller number of investigational devices accounted for the rest. Type 1A endoleak was the most common indication for re-intervention among all devices except for AFX and ancure devices, proximal migration was a frequent presentation with AneuRx. AFX devices more frequently presented with a type III and ancure devices more frequently presented with a type IB endoleak.

CONCLUSIONS

Serious failure modes after EVAR differ between endografts and occur throughout the follow-up period. This is important to guide targeted interrogation of surveillance studies and follow-up schedules, even for discontinued devices, as well as comparisons between various series and estimation of EVAR failure rates.

CLINICAL IMPACT

Surveillance after EVAR is critical for long term success of the repair, understanding of the differential modes of failure of every graft available is important in the longitudinal evaluation of these endografts. Equally important is the understanding of the modes of failure of legacy endografts that are no longer on the market but still being followed, in order to be able to tailor a surveillance regiemn and the evntual repair if needed.

Use of physician-modified inverted limb in conjunction with Zenith fenestrated stent graft to rescue failed previous endovascular and open repair

OBJECTIVE

To evaluate outcomes and performance of inverted limbs (ILs) when used in conjunction with Zenith fenestrated stent grafts (Zfens) to treat patients with short distance between the lowest renal artery (RA) and aortic or graft bifurcation (A/GB).

METHODS

This study was a multicenter, retrospective review of prospectively maintained database of patients with complex aortic aneurysms, failed endovascular aneurysm repair (EVAR), or open surgical repair (OSR) with short distance between LRA and A/GB treated using a combination of Zfen and an IL between 2013 and 2023. Endpoints included technical success, aneurysm sac regression, long-term device integrity, and target vessel patency. We defined technical success as implantation of the device with no endoleak, conversion to an aorto-uni-iliac or OSR.

RESULTS

During this time, 52 patients underwent endovascular rescue of failed repair. Twenty (38.5%) of them required relining of the failed repairs using IL due to lowest RA to A/GB length restrictions. Two patients had undergone rescue with a fenestrated cuff alone but developed type III endoleaks. One patient with no previous implant had a short distance between the lowest RA and aortic bifurcation to accommodate the bifurcated distal device, and two patients had failed OSR or anastomotic pseudoaneurysms. The majority (94%) were men with a mean age of 76.8 ± 6.1 years. The mean aortic neck diameter and aneurysm size were 32 ± 4 cm and 7.2 ± 1.3 cm, respectively. The median time laps between initial repair and failure was 36 months (interquartile range [IQR], 24-54 months). Sixteen patients (80%) were classified as American Society of Anesthesiologists class III, whereas four were class IV. Seventy-eight vessels were targeted and successfully incorporated. Technical success was 100%, and median estimated blood loss was 100 mL (IQR, 100-200 mL). Mean fluoroscopy time and dose were 61 ± 18 minutes and 2754 ± 1062 mGy, respectively. Average hospital length of stay was 2.75 ± 2.15 days. Postoperative complication occurred in one patient who required lower extremity fasciotomy for compartment syndrome. At a median follow-up of 50 months (IQR, 18-58 months), there were no device migration, components separation, aneurysmal related mortality, and type I or type III endoleak. Aneurysm sac regression (95%) or stabilization (5%) was observed in all patients, including in four patients (25%) with type II endoleak.

CONCLUSIONS

The use of IL in conjunction with Zfen to treat patients with short distance between the lowest RA and A/GB is safe, effective, and has excellent long-term results. The technique expands the indication of Zfen, especially in patients with failed previous EVAR.

A dedicated risk prediction model of 1-year mortality following endovascular aortic aneurysm repair involving the renal-mesenteric arteries

OBJECTIVE

Treatment goals of prophylactic endovascular aortic repair of complex aneurysms involving the renal-mesenteric arteries (complex endovascular aortic repair [cEVAR]) include achieving both technical success and long-term survival benefit. Mortality within the first year after cEVAR likely indicates treatment failure owing to associated costs and procedural complexity. Notably, no validated clinical decision aid tools exist that reliably predict mortality after cEVAR. The purpose of this study was to derive and validate a preoperative prediction model of 1-year mortality after elective cEVAR.

METHODS

All elective cEVARs including fenestrated, branched, and/or chimney procedures for aortic disease extent confined proximally to Ishimaru landing zones 6 to 9 in the Society for Vascular Surgery Vascular Quality Initiative were identified (January 2012 to August 2023). Patients (n = 4053) were randomly divided into training (n = 3039) and validation (n = 1014) datasets. A logistic regression model for 1-year mortality was created and internally validated by bootstrapping the AUC and calibration intercept and slope, and by using the model to predict 1-year mortality in the validation dataset. Independent predictors were assigned an integer score, based on model beta-coefficients, to generate a simplified scoring system to categorize patient risk.

RESULTS

The overall crude 1-year mortality rate after elective cEVAR was 11.3% (n = 456/4053). Independent preoperative predictors of 1-year mortality included chronic obstructive pulmonary disease, chronic renal insufficiency (creatinine >1.8 mg/dL or dialysis dependence), hemoglobin <12 g/dL, decreasing body mass index, congestive heart failure, increasing age, American Society of Anesthesiologists class ≥IV, current tobacco use, history of peripheral vascular intervention, and increasing extent of aortic disease. The 1-year mortality rate varied from 4% among the 23% of patients classified as low risk to 23% for the 24% classified as high risk. Performance of the model in validation was comparable with performance in the training data. The internally validated scoring system classified patients roughly into quartiles of risk (low, low/medium, medium/high and high), with 52% of patients categorized as medium/high to high risk, which had corresponding 1-year mortality rates of 11% and 23%, respectively. Aneurysm diameter was below Society for Vascular Surgery recommended treatment thresholds (<5.0 cm in females, <5.5 cm in males) in 17% of patients (n = 679/3961), 41% of whom were categorized as medium/high or high risk. This subgroup had significantly increased in-hospital complication rates (18% vs 12%; P = .02) and 1-year mortality (13% vs 5%; P < .0001) compared with patients in the low- or low/medium-risk groups with guideline-compliant aneurysm diameters (≥5.0 cm in females, ≥5.5 cm in males).

CONCLUSIONS

This validated preoperative prediction model for 1-year mortality after cEVAR incorporates physiological, functional, and anatomical variables. This novel and simplified scoring system can effectively discriminate mortality risk and, when applied prospectively, may facilitate improved preoperative decision-making, complex aneurysm care delivery, and resource allocation.

Transition from Open Repair to Endovascular Aneurysm Repair for Rupture Aortic Aneurysms throughout a 16-Year Period of Time in a Single Tertiary Center

BACKGROUND

Endovascular aneurysm repair (EVAR) is recommended as the first option for both elective and ruptured abdominal aortic aneurysms (rAAAs) with suitable anatomy. The aim of this study was to evaluate the outcomes of the gradual adoption of ruptured EVAR (rEVAR) as first option in the management of rAAAs in a reference tertiary center over a 16 year-period.

METHODS

A retrospective analysis of prospectively collected clinical data was undertaken, including all patients that were treated for rAAA infrarenal or juxtarenal either with open surgical repair (OSR) or EVAR from 2006-2023. Three periods were identified and analyzed: Initial (2006-2011); intermediate (2012-2017); and current (2018-2023). The primary outcomes were the 30-day mortality rate in relation to the changing pattern of treatment. Secondary outcomes were re-intervention and mortality during the follow up period.

RESULTS

Two hundred patients were treated for rAAA; 52% by endovascular means [EVAR (94), Ch-EVAR (9), and branched endovascular aneurysm repair (1)] and 48% by OSR (96). In the initial period, 61 patients were treated for rAAA (21% EVAR vs. 79% OSR), 68 in intermediate patients (47% EVAR vs. 53% OSR), and 71 in current period (83% EVAR vs. 17% OSR). Only in the current period juxta -renal rAAAs were treated by endovascular means (14%). The 30-day mortality rate was 46% in initial period (31% for EVAR vs. 50% for OSR), 64% in second period (46% in EVAR vs. 80% for OSR), and 35% in third period (25% for EVAR vs. 83% for OSR). The mean follow up did not differ between the groups, (EVAR 28.3 ± 2 months, vs. OSR 33.1 ± 3 months, P = 0.56). The survival rate did not differ between the groups; in rEVAR was 82% (SE 5%), 74% (SE 6%), 68% (SE 6.5%), and 63% (SE 7.7%) at 12, 24, 36, and 48 months, respectively, and in OSR was 76% (SE 7%), 66% (SE 8%), and 56% (SE 9.5%) at 6, 24, and 48 months, respectively (P = 0.544).

CONCLUSIONS

Through a 16-year period, the implementation of EVAR as treatment of choice for rAAAs over OSR resulted in a noticeable reduction in the 30-day mortality. rEVAR was feasible in over 80% of rAAA patients.

Iliac tortuosity increases reinterventions but not adverse outcomes following repair of juxtarenal aneurysms using physician-modified endografts

OBJECTIVE

Increased angulation of the proximal aortic neck has been associated with complications following endovascular repair of infrarenal aortic aneurysms, including increased incidence of endoleaks, stent migration, secondary interventions, and conversions. However, knowledge on the impact of aortoiliac tortuosity on outcomes following fenestrated repair remains limited. This study aims to quantify the effect of aortoiliac tortuosity on outcomes following fenestrated repair.

METHODS

A single-center, retrospective review of all patients who underwent a physician-modified endovascular repair for the treatment of juxtarenal aortic aneurysms under a single physician-sponsored investigation device exemption study from 2011 to 2021 was performed. Center luminal lines and geometric distances were obtained using TeraRecon software (San Mateo, CA). A tortuosity index was calculated (tortuosity index = centerline distance/geometric line distance) for each iliac vessel as well as for the infrarenal aorta according to Society for Vascular Surgery reporting standards. Aortic and iliac tortuosity were assessed independently and stratified as low and high. Demographics, comorbidities, anatomic and operative details, and outcomes were compared using univariable and multivariable analysis.

RESULTS

A total of 135 patients were identified. Thirty-eight patients (28%) had high aortic tortuosity, and 55 patients (42%) had high iliac tortuosity. Patients with high tortuosity were older (aortic: 78 vs 76 years; P = .04; iliac: 78 vs 75 years; P = .01) and differed by sex. Twenty-two percent of men and 50% of women had high aortic tortuosity (P = .01). Forty-seven percent of men and 20% of women had high iliac tortuosity (P = .01). There were no differences in comorbidities based on aortic tortuosity, but coronary artery disease (high: 58% vs low: 36%; P = .01) and hypertension (high: 69% vs low: 86%; P = .02) differed based on iliac tortuosity. Aneurysm diameter was larger for patients with high iliac tortuosity (72 mm vs 64 mm; P < .01), and fluoroscopy time was longer for patients with high aortic tortuosity (41 vs 31 minutes; P = .02). When outcomes were assessed, high iliac tortuosity was associated with increased rate of reinterventions (hazard ratio, 2.6; 95% confidence interval, 1.2-6.0) and type 1 or 3 endoleak (hazard ratio, 5.2; 95% confidence interval, 1.7-16); however, all other outcomes were similar.

CONCLUSIONS

Among patients treated with physician-modified endovascular repair for juxtarenal aneurysms, iliac tortuosity but not aortic tortuosity, is associated with increased reinterventions and type 1 or type 3 endoleaks. Long-term follow-up is critical for patients with high iliac tortuosity to ensure that high-risk endoleaks are identified and treated early to avoid the risk of rupture.

Effectiveness of Intra-operative Contrast-Enhanced Ultrasound Assessment to Optimize Type II Endoleak Embolization

PURPOSE

To analyze the effectiveness of type II endoleaks (T2E) embolization using intra-operative contrast-enhanced ultrasound (CEUS).

METHODS

Consecutive patients treated for T2E underwent a standardized protocol with trans-arterial or trans-lumbar access, large volume embolization, onlay fusion, and intra-operative CEUS. Technical success was defined by exclusion of endoleak by CEUS.

RESULTS

Twenty-six patients (mean age 81 ± 11 years old; 89% male) were treated. The mean aneurysm sac enlargement was 11 ± 8 mm from T2E diagnosis. Embolization was performed using Onyx® 18 in all patients with adjunctive coils in 13 patients (50%). After the first embolization, CEUS documented residual T2E in 13 patients (50%). Ten patients (38%) had additional embolization, which successfully eradicated the T2E in seven of them. Technical success was 50% after the first embolization attempt and 77% after additional attempts guided by CEUS (P = 0.080). There was no mortality. Median imaging follow-up was 22 months. Among the 20 patients with no residual T2E on completion CEUS, 16 (80%) had sac stabilization and none required additional interventions for T2E. Of the six patients with residual T2Es on CEUS, three had sac stabilization (50%) and one required additional reintervention for T2E. There was one late aortic rupture at 56 months.

CONCLUSION

One in two patients treated by T2E embolization had residual endoleak on intra-operative CEUS after a first embolization attempt, decreasing to one in four patients after multiple attempts. A negative completion CEUS following embolization was associated with higher rates of sac stabilization and no need for additional T2E embolization.

Modified Harborview Risk Score accurately predicts mortality for patients with ruptured abdominal aortic aneurysm

OBJECTIVE

The modified Harborview Risk Score (HRS) is a simple measure initially derived from a single institutional dataset used to predict ruptured abdominal aortic aneurysm (rAAA) repair survival preoperatively using basic labs and vital signs collected upon presentation. However, validation of this widely applicable scoring system has not been performed. This study aims to validate this scoring system using a large multi-institutional database.

METHODS

All patients who underwent repair of an rAAA from 2011 to 2018 in the National Surgical Quality Improvement Program (NSQIP) and at a single academic medical center were included. The modified HRS was calculated by assigning 1 point for each of the following: age >76 years, creatinine >2 mg/dL, international normalized ratio >1.8, and any systolic blood pressure less than 70 mmHg. Assessment of the prediction model was then completed. Using a primary outcome measure of 30-day mortality, the receiver operating characteristic area under the curve was calculated. The discrimination between datasets was compared using a Delong test. Mortality rates for each score were compared between datasets using the Pearson χ2 test. Comparative analysis for patients with a score of 4 was limited due to a small sample size.

RESULTS

A total of 1536 patients were identified using NSQIP, and 163 patients were assessed in the institutional dataset. There were 518 patients with a score of 0 (455 NSQIP, 63 institutional), 676 patients with a score of 1 (617 NSQIP, 59 institutional), 391 patients with a score of 2 (364 NSQIP, 27 institutional), 106 with a score of 3 (93 NSQIP, 13 institutional), and 8 patients with a score of 4 (7 NSQIP, 1 institutional). No difference was found in the receiver operating characteristic area under the curves between datasets (P = .78). Thirty-day mortality was 10% NSQIP vs 22% institutional for a score of 0; 28% NSQIP vs 36% institutional for a score of 1; 41% NSQIP vs 44% institutional for a score of 2; 45% NSQIP vs 69% institutional for a score of 3; and 57% NSQIP vs 100% institutional for a score of 4. Score 0 was the only score with a significant mortality rate difference between datasets (P = .01).

CONCLUSIONS

The modified HRS is confirmed to be broadly applicable as a clinical decision-making tool for patients presenting with rAAAs. Therefore, this easily applicable model should be applied for all patients presenting with rAAAs to assist with provider and patient decision-making prior to proceeding with repair.

Preoperative predictors of nonhome discharge after fenestrated-branched endovascular repair of complex abdominal and thoracoabdominal aortic aneurysms

BACKGROUND

Nonhome discharge (NHD) has significant implications for patient counseling and discharge planning and is frequently required following fenestrated-branched endovascular aortic repair (FB-EVAR) of complex abdominal aortic aneurysms (CAAA) and thoracoabdominal aortic aneurysms (TAAA). We aimed to identify preoperative predictors of NHD after elective FB-EVAR for CAAA and TAAA and develop a risk calculator able to predict NHD.

METHODS

A retrospective review of prospectively collected data on all patients undergoing FB-EVAR between January 2007 and December 2021 at a single institution was performed. Exclusion criteria were admission from a nonhome setting, emergency and repeat FB-EVAR, and discharge to an unknown destination. The cohort was randomly split into separate development (70% of patients) and validation (30%) cohorts to develop a predictive calculator for NHD. Independent variables associated with NHD were assessed in a series of logistic regression analyses from 100 bootstrapped samples of the development set, and a model was developed using the most predictive variables. Resulting parameter estimates were applied to data in the validation set to assess model discrimination and calibration.

RESULTS

From the initial cohort of 712 FB-EVAR patients, 644 were included in the study (74% male; mean age, 75.4 ± 7.6 years), including 452 with CAAA (70%) and 192 with TAAA (30%). Early mortality occurred in eight patients (1.2%; 5 in CAAA and 3 in TAAA) and the median hospital stay was 5 days (4 for CAAA and 7 for TAAA). Ninety-seven patients (15%) had a NHD. On multivariable analysis, older age (per year, odds ratio [OR], 1.08; P < .001), female gender (OR, 3.03; P < .001), smoking (OR, 2.86; P = .01), congestive heart failure (OR, 3.05; P = .004), peripheral artery disease (OR, 1.81; P = .07), and extent I (OR, 3.17), II (OR, 2.84), and III (OR, 2.52; all P = .08) TAAAs were associated with an increased likelihood of NHD in the development set. Based on these factors, the risk calculator was developed which accurately predicts NHD in the validation set with an area under the curve of 0.7.

CONCLUSIONS

Older, female smokers with congestive heart failure and peripheral artery disease and more extensive aneurysms are at highest risk of NHD after FB-EVAR. Using only preoperative factors, our risk calculator can predict accurately who will have a NHD, allowing enhanced preoperative patient counselling and accelerated hospital discharge.

Reducing aneurysm sac growth and secondary interventions following endovascular abdominal aortic aneurysm repair by preemptive coil embolization of the inferior mesenteric artery and lumbar arteries

OBJECTIVE

Type II endoleak (EL-2) is the most common complication following endovascular aneurysm repair (EVAR), leading to continued sac growth and potential rupture. In this study, we examined the association between patency of the inferior mesenteric artery (IMA) and lumbar arteries (LAs) with respect to sac growth. The effect of preemptive embolization of the IMA and/or LAs on the need for secondary interventions for sac growth post-EVAR was also evaluated.

METHODS

A retrospective cohort study was performed on consecutive patients who underwent EVAR for non-ruptured, infrarenal abdominal aortic aneurysms (AAAs) from January 2012 to December 2020. A select group of patients underwent preemptive embolization of the IMA and/or LA. Patients with any types I, III, or IV endoleaks were excluded. Patency of the IMA and LA on preoperative computed tomography angiogram (CTA) was evaluated on TeraRecon workstation. All secondary interventions to treat EL-2 were recorded. Sac growth was defined as centerline axial diameter increase of ≥5 mm on follow-up CTA.

RESULTS

A total of 300 patients (mean age, 74 ± 8.5 years; 83.7% male) underwent EVAR. Ninety-nine patients had preemptive embolization of the IMA and/or LA. Mean follow-up of the cohort was 59.3 ± 30.5 months. Thirty-six patients (12%) demonstrated sac growth on follow-up; 12 of these (33.3%) had preemptive embolization. The median time until detection of sac growth was 28.8 months (interquartile range, 15.2-46.5 months), with a mean growth of 10.1 ± 6.4 mm. Sac growth was significantly associated with presence of EL-2: 27 of 36 (75%) with EL-2 vs 9 of 36 (25%) without EL-2 (P < .001). Patients with sac growth had a higher mean total number (2.6 ± 1.5) of patent lower LAs (L3, L4) compared with those without (2.0 ± 1.4; P = .03). Patency of L1, L2, and L3 LAs were not associated with sac growth. However, patency of at least one L4 LA was significantly associated with sac growth (14.8% vs 7.7%; P = .04). The highest incidence of sac growth (17.6%) was seen when both IMA and L4 LA were patent; significantly different from the lowest incidence (5.3%) when both were occluded preoperatively (P = .018). Preemptive coiling of the IMA and/or LA significantly reduced the need for post-EVAR secondary intervention for sac growth. Freedom from post-EVAR secondary intervention was achieved in 92 of 99 (92.9%) pre-EVAR coiled patients vs 163 of 201 (81.5%) patients who did not undergo pre-EVAR coiling (P = .009).

CONCLUSIONS

Preemptive coil embolization of the IMA and LAs, especially L4 LA, reduces the need for secondary interventions for sac growth, potentially improving the long-term durability of EVAR.

Trends in AAA Repair in Australia Over Twenty Years

Background

The advent of endovascular techniques has revolutionised the treatment of abdominal aortic aneurysms (AAA). Many countries have seen a transition from open AAA repair (OAR) to endovascular AAA repair (EVAR) over the past 25 years. The only study done in Australia that describes this change was done in the private sector. Majority of healthcare in Australia is delivered through the public, universal healthcare system. The aim of this study was to evaluate the trends in AAA repair in the Australian public sector over the past two decades.

Methods

The Australian Institute of Health and Welfare (AIHW) Procedures Data Cubes from the National Hospitals Data Collection was used to extract data pertaining to AAA repairs from 2000 to 2021. Population data from the Australian Bureau of Statistics was used to calculate incidence of each type of repair per 100,000 population.

Results

There were 65,529 AAA repairs performed in the Australian public sector from 2000 to 2021. EVARs accounted for 64.4% (42,205) and OARs accounted for 35.6% (23, 324) of them. EVAR surpassed OAR as the preferred method of AAA repair in 2006. This trend was observed in both males and females and across all age groups.

Conclusion

There was a consistent and steady transition from OAR to EVAR over the 21 year period with EVAR surpassing OAR as the preferred method of AAA repair relatively early in Australia compared to other countries. Further research that investigates medium- and long-term outcomes of newer stent grafts is needed to further ascertain the continued viability and effectiveness of this trend in AAA treatment.

Development of an Artificial Intelligence Tool for Intraoperative Guidance During Endovascular Abdominal Aortic Aneurysm Repair

BACKGROUND

Adverse events during surgery can occur in part due to errors in visual perception and judgment. Deep learning is a branch of artificial intelligence (AI) that has shown promise in providing real-time intraoperative guidance. This study aims to train and test the performance of a deep learning model that can identify inappropriate landing zones during endovascular aneurysm repair (EVAR).

METHODS

A deep learning model was trained to identify a "No-Go" landing zone during EVAR, defined by coverage of the lowest renal artery by the stent graft. Fluoroscopic images from elective EVAR procedures performed at a single institution and from open-access sources were selected. Annotations of the "No-Go" zone were performed by trained annotators. A 10-fold cross-validation technique was used to evaluate the performance of the model against human annotations. Primary outcomes were intersection-over-union (IoU) and F1 score and secondary outcomes were pixel-wise accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV).

RESULTS

The AI model was trained using 369 images procured from 110 different patients/videos, including 18 patients/videos (44 images) from open-access sources. For the primary outcomes, IoU and F1 were 0.43 (standard deviation ± 0.29) and 0.53 (±0.32), respectively. For the secondary outcomes, accuracy, sensitivity, specificity, NPV, and PPV were 0.97 (±0.002), 0.51 (±0.34), 0.99 (±0.001). 0.99 (±0.002), and 0.62 (±0.34), respectively.

CONCLUSIONS

AI can effectively identify suboptimal areas of stent deployment during EVAR. Further directions include validating the model on datasets from other institutions and assessing its ability to predict optimal stent graft placement and clinical outcomes.

Decreasing prevalence of centers meeting the Society for Vascular Surgery abdominal aortic aneurysm guidelines in the United States

OBJECTIVE

Based on data supporting a volume-outcome relationship in elective aortic aneurysm repair, the Society of Vascular Surgery (SVS) guidelines recommend that endovascular aortic repair (EVAR) be localized to centers that perform ≥10 operations annually and have a perioperative mortality and conversion-to-open rate of ≤2% and that open aortic repair (OAR) be localized to centers that perform ≥10 open aortic operations annually and have a perioperative mortality ≤5%. However, the number and distribution of centers meeting the SVS criteria remains unclear. This study aimed to estimate the temporal trends and geographic distribution of Centers Meeting the SVS Aortic Guidelines (CMAG) in the United States.

METHODS

The SVS Vascular Quality Initiative was queried for all OAR, aortic bypasses, and EVAR from 2011 to 2019. Annual OAR and EVAR volume, 30-day elective operative mortality for OAR or EVAR, and EVAR conversion-to-open rate for all centers were calculated. The SVS guidelines for OAR and EVAR, individually and combined, were applied to each institution leading to a CMAG designation. The proportion of CMAGs by region (West, Midwest, South, and Northeast) were compared by year using a χ2 test. Temporal trends were estimated using a multivariable logistic regression for CMAG, adjusting by region.

RESULTS

Overall, 67,865 patients (49,264 EVAR; 11,010 OAR; 7591 aortic bypasses) at 336 institutions were examined. The proportion of EVAR CMAGs increased nationally by 1.7% annually from 51.6% (n = 33/64) in 2011 to 67.1% (n = 190/283) in 2019 (β = .05; 95% confidence interval [CI], 0.01-0.09; P = .02). The proportion of EVAR CMAGs across regions ranged from 27.3% to 66.7% in 2011 to 63.9% to 72.9% in 2019. In contrast, the proportion of OAR CMAGs has decreased nationally by 1.8% annually from 32.8% (n = 21/64) in 2011 to 16.3% (n = 46/283) in 2019 (β = -.14; 95% CI, -0.19 to -0.10; P < .01). Combined EVAR and OAR CMAGs were even less frequent and decreased by 1.5% annually from 26.6% (n = 17/64) in 2011 to 13.1% (n = 37/283) in 2019 (β = -.12; 95% CI, -0.17 to -0.07; P < .01). In 2019, there was no significant difference in regional variation of the proportion of combined EVAR and OAR CMAGs (P = .82).

CONCLUSIONS

Although an increasing proportion of institutions nationally meet the SVS guidelines for EVAR, a smaller proportion meet them for OAR, with a concerning downward trend. These data question whether we can safely offer OAR at most institutions, have important implications about sufficient OAR exposure for trainees, and support regionalization of OAR.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

A hemodynamic study of blood flow models on various stent graft configurations during aorto-iliac reconstruction

PURPOSE

To compare the hemodynamic performance of three (Bottom Up non-ballet, Top-Down non-ballet, Top Down ballet) idealized stent graft configurations used during endovascular repair of abdominal aortic aneurysms, under the influence of various rheological models.

METHODS

Ten rheological models are assumed and a commercial finite volume solver is employed for the simulation of blood flow under realistic boundary conditions. An appropriate mesh convergence study is performed and five hemodynamic variables are computed: the time average wall shear stress (TAWSS), oscillatory shear index (OSI), relative residence time (RRT), endothelial cell activation potential (ECAP) and displacement force (DF) for all three configurations.

RESULTS

The choice of blood flow model may affect results, but does not constitute a significant determinant on the overall performance of the assumed stent grafts. On the contrary, stent graft geometry has a major effect. Specifically, the Bottom Up non-ballet type is characterized by the least favorable performance presenting the lowest TAWSS and the highest OSI, RRT and ECAP values. On the other hand, the Top Down ballet type presents hemodynamic advantages yielding the highest TAWSS and lowest OSI, RRT and ECAP average values. Furthermore, the ballet type is characterized by the lowest DF, although differences observed are small and their clinical relevance uncertain.

CONCLUSIONS

The effect of the assumed rheological model on the overall performance of the grafts is not significant. It is thus relatively safe to claim that it is the type of stent graft that determines its overall performance rather than the adopted blood flow model.

Bibliometric analysis of the top 100 most-cited articles on branch reconstruction in endovascular aortic repair

With the global acceptance of endovascular aortic repair (EVAR) for aortic diseases, one of the most common issues in EVAR is the preservation of critical aortic branches. Despite the fact that many studies on EVAR-assisted endovascular branch reconstruction techniques have been published. There were few bibliometric analyses that focused on branch rebuilding in endovascular aortic repair. In this study, we aim to analyze the characteristics of the 100 most-cited articles on branch reconstruction in Endovascular Aortic Repair. The most popular articles retrospectively searched on the Web of Science were published between 1999 and 2018, with 10480 citations in total (an average of 551.58 citations per year). The top-cited article was 281 citations. The peak years of citations was 2019 (1051 citations). Journal of Vascular Surgery published the most articles (46 articles) and was the most-cited journal (5055 citations), and the United States was the country with the greatest number of publications (43 articles). Cleveland Clinic was the most influential institution with 20 articles. Fenestration technique was the major topic area of interest and trend (63 articles mentioned). Customised device was the most widely used endograft (52 articles mentioned). Renal artery was the most frequently reconstructed branch of aorta (70 articles mentioned). Our analysis showed the endovascular branch reconstruction in EVAR developed rapidly over the past 20 years. Continued exploration and cooperation between specialties and manufacturers on endograft design and modifications will further enhance knowledge of disease intervention and treatment.

Multicenter Comparative Analysis of Late Open Conversion in Patients With Adherence and Nonadherence to Instructions for Use Endovascular Aneurysm Repair

PURPOSE

The widespread adoption of endovascular aneurysm repair (EVAR) as preferred treatment modality for abdominal aortic aneurysm (AAA) has enlarged the number of patients needing open surgical conversion (OSC). The relationship between adherence to Instructions For Use (IFU) and EVAR long-term outcomes remains controversial. The aim of this study is to compare preoperative differences and postoperative outcomes between EVAR patients not adjusted to IFU and adjusted to IFU who underwent OSC.

METHODS

This multicenter retrospective study reviewed 33 explanted EVARs between January 2003 and December 2019 at 14 Vascular Units. Patients were included if OSC occurred >30 days after implantation and excluded if explantation was performed to treat an endograft infection, aortic dissection, or traumatic transections. Variables analyzed included baseline characteristics, adherence to IFU, implant and explant procedural details, secondary reinterventions, and postoperative outcomes.

RESULTS

Fifteen explanted patients (15/33, 45.5%) were identified not accomplished to IFU (out-IFU) at initial EVAR vs 18 explanted patients adjusted (in-IFU). During follow-up, a mean of 1.73±1.2 secondary reinterventions were performed, with more type I endoleaks treated in the subgroup out-IFU: 16.7% vs 6.3% in-IFU patients and more type III endoleaks (8.3% vs 0%). Patients out-IFU had shorter mean interval from implant to explant: 47.60±28.8 months vs 71.17±48. Type II endoleak was the most frequent indication for explantation. Low-flow endoleaks (types II, IV, V) account for 44% of indications for OSC in subgroup of patients in-IFU, compared with 13.3% in patients out-IFU and high-flow endoleaks (types I and III) were the main indication for patients out-IFU (33.3% vs 16.7% in-IFU). Total endograft explantation was performed in 57.5% of cases (19/33) and more suprarenal clamping was required in the subgroup out-IFU. Overall, 30-day mortality rate was 12.1% (4/33): 20% for patients out-IFU and 5.6% in-IFU.

CONCLUSIONS

In our experience, type II endoleak is the most common indication for conversion and differences have been found between patients treated outside IFU with explantation taking place earlier during follow-up, mainly due to high-flow endoleaks and with higher mortality in comparison with patients adjusted to IFU. Ongoing research is required to delve into these differences.

General Surgery Trainee Cases Over Time: Postgraduate Year Matters

BACKGROUND

Trainees and attending surgeons alike have concerns about resident and fellow operative volume/breadth, competency, and overall readiness for practice. This is an important topic within surgical graduate medical education. Our goal was to analyze the change in general surgery trainee operative experience over time by postgraduate year.

METHODS

Institutional operative records from two corresponding three-month time periods in 2009 and 2018 at the residency program's main hospital site were reviewed. Cases assisted on by general, vascular, or thoracic surgery trainees were included. The number of cases per level, combination of trainees in each case, and categories of cases were compared over time.

RESULTS

There were 1940 cases in 2009 and 1967 cases in 2018 over the respective time periods. The distribution of trainees was different (P < .001), with a similar number of PGY-1 and fellow cases, a decrease in PGY-2 and PGY-5 cases, and an increase in PGY-3 and PGY-4 cases. The number of cases with two trainees, double scrubbed cases, increased from 19.6% to 26.8% (P < .001). In addition, there were differences in the resident years that double scrubbed cases together, an increase in robotic and endovascular surgery, and a decrease in open cases.

CONCLUSIONS

This analysis of cases shows that resident operative volume over approximately a decade has been largely preserved, with some change in the distribution of cases based on trainee level, an increase in cases with more than one trainee, and a rise of minimally invasive surgery with a corresponding decrease in open cases.

Patient-specific computational flow simulation reveals significant differences in paravisceral aortic hemodynamics between fenestrated and branched endovascular aneurysm repair

Background

Endovascular aneurysm repair with four-vessel fenestrated endovascular aneurysm repair (fEVAR) or branched endovascular aneurysm repair (bEVAR) currently represent the forefront of minimally invasive complex aortic aneurysm repair. This study sought to use patient-specific computational flow simulation (CFS) to assess differences in postoperative hemodynamic effects associated with fEVAR vs bEVAR.

Methods

Patients from two institutions who underwent four-vessel fEVAR with the Cook Zenith Fenestrated platform and bEVAR with the Jotec E-xtra Design platform were retrospectively selected. Patients in both cohorts were treated for paravisceral and extent II, II, and V thoracoabdominal aortic aneurysms. Three-dimensional finite element volume meshes were created from preoperative and postoperative computed tomography scans. Boundary conditions were adjusted for body surface area, heart rate, and blood pressure. Pulsatile flow simulations were performed with equivalent boundary conditions between preoperative and postoperative states. Postoperative changes in hemodynamic parameters were compared between the fEVAR and bEVAR groups.

Results

Patient-specific CFS was performed on 20 patients (10 bEVAR, 10 fEVAR) with a total of 80 target vessels (40 renal, 20 celiac, 20 superior mesenteric artery stents). bEVAR was associated with a decrease in renal artery peak flow rate (-5.2% vs +2.0%; P < .0001) and peak pressure (-3.4 vs +0.1%; P < .0001) compared with fEVAR. Almost all renal arteries treated with bEVAR had a reduction in renal artery perfusion (n = 19 [95%]), compared with 35% (n = 7) treated with fEVAR. There were no significant differences in celiac or superior mesenteric artery perfusion metrics (P = .10-.27) between groups. Time-averaged wall shear stress in the paravisceral aorta and branches also varied significantly depending on endograft configuration, with bEVAR associated with large postoperative increases in renal artery (+47.5 vs +13.5%; P = .002) and aortic time-averaged wall shear stress (+200.1% vs -31.3%; P = .001) compared with fEVAR. Streamline analysis revealed areas of hemodynamic abnormalities associated with branched renal grafts which adopt a U-shaped geometry, which may explain the observed differences in postoperative changes in renal perfusion between bEVAR and fEVAR.

Conclusions

bEVAR may be associated with subtle decreases in renal perfusion and a large increase in aortic wall shear stress compared with fEVAR. CFS is a novel tool for quantifying and visualizing the unique patient-specific hemodynamic effect of different complex EVAR strategies.

Clinical Relevance

This study used patient-specific CFS to compare postoperative hemodynamic effects of four-vessel fenestrated endovascular aneurysm repair (fEVAR) and branched endovascular aneurysm repair (bEVAR) in patients with complex aortic aneurysms. The findings indicate that bEVAR may result in subtle reductions in renal artery perfusion and a significant increase in aortic wall shear stress compared with fEVAR. These differences are clinically relevant, providing insights for clinicians choosing between these approaches. Understanding the patient-specific hemodynamic effects of complex EVAR strategies, as revealed by CFS, can aid in future personalized treatment decisions, and potentially reduce postoperative complications in aortic aneurysm repair.

Operation time and clinical outcomes for open infrarenal abdominal aortic aneurysms to remain stable in the endovascular era

Objective

Endovascular aortic repair (EVAR) has become a routine procedure worldwide. Ultimately, the increasing number of EVAR cases entails changing conditions for open surgical repair (OSR) regarding patient selection, complexity, and surgical volume. This study aimed to assess the time trends of open abdominal aortic aneurysm (AAA) repair in a high-volume single center in Austria over a period of 20 years, focusing on the operation time and clinical outcomes.

Materials and methods

A retrospective analysis of all patients treated for infrarenal AAAs with OSR or EVAR between January 2000 and December 2019 was performed. Infrarenal AAA was defined as the presence of a >10-mm aortic neck. Cases with ruptured or juxtarenal AAAs were excluded from the analysis. Two cohorts of patients treated with OSR at different time periods, namely, 2000-2009 and 2010-2019, were assessed regarding demographical and procedure details and clinical outcomes. The time periods were defined based on the increasing single-center trend toward the EVAR approach from 2010 onward.

Results

A total of 743 OSR and 766 EVAR procedures were performed. Of OSR cases, 589 were infrarenal AAAs. Over time, the EVAR to OSR ratio was stable at around 50:50 (p = 0.488). After 2010, history of coronary arterial bypass (13.4% vs. 7.2%, p = 0.027), coronary artery disease (38.1% vs. 25.1%, p = 0.004), peripheral vascular disease (35.1% vs. 21.3%, p = 0.001), and smoking (61.6% vs. 34.3%, p < 0.001) decreased significantly. Age decreased from 68 to 66 years (p = 0.023). The operation time for OSR remained stable (215 vs. 225 min, first vs. second time period, respectively, p = 0.354). The intraoperative (5.8% vs. 7.2%, p = 0.502) and postoperative (18.3% vs. 20.8%, p = 0.479) complication rates also remained stable. The 30-day mortality rate did not change over both time periods (3.0% vs. 2.4%, p = 0.666).

Conclusion

Balanced EVAR to OSR ratio, similar complexity of cases, and volume over the two decades in OSR showed stable OSR time without compromise in clinical outcomes.

Possible implications of device-specific variability in post-endovascular aneurysm repair sac regression and endoleaks for surveillance categorization

OBJECTIVE

Significant sac regression during early surveillance has been shown to best predict reintervention-free long-term surveillance after endovascular aneurysm repair (EVAR). Furthermore, a persistent endoleak has been related to a worse outcome. Individualized surveillance algorithms based on these findings have been suggested. There are no studies comparing the performance of different stent grafts regarding sac regression, the presence of type II endoleaks, and their possible implications for individualized surveillance. The objective of this study was to evaluate device-specific differences and how these may affect patient categorization for surveillance.

METHODS

Patients were treated electively with standard EVAR between 2005 and 2015 using three different devices (Zenith by Cook, Excluder by Gore, and Endurant by Medtronic). The data were reviewed retrospectively until 2020. Patients' computed tomography angiographies (CTAs) at 30 days and at 2 years were analyzed for freedom from endoleaks and for sac regression of ≥5 mm. Reinterventions during long-term surveillance were counted. Patients were categorized according to the presence of any endoleak and sac regression at 30 days and 2 years, and the probability of reintervention-free long-term surveillance was evaluated based on these findings.

RESULTS

A total of 435 patients were treated for an abdominal aortic aneurysm with EVAR during the study period. At 30 days, 80.0% (n = 339) of the patients were free from endoleaks, and at 2 years, 78.9% (n = 273) were free from endoleaks. There was a significant difference in endoleak rate at 30 days and 2 years between the devices (P < .001 and P = .001). There was no significant difference in sac regression between the devices at 2 years (P = .096). The categorization at 30 days based on endoleak status had a sensitivity of 44.9%, specificity of 87.4%, and negative predictive value of 84.1% for finding a reintervention-requiring complication during long-term follow-up. The corresponding figures at 2 years were 63.3%, 91.4%, and 89.4%, respectively. The combination of freedom from endoleaks and sac regression of ≥5 mm in the 2-year CTA best predicted an uneventful long-term surveillance. Patients who met this criterion had a 95.6% probability (negative predictive value) of having a reintervention-free long-term surveillance.

CONCLUSIONS

There are significant differences in the prevalence of endoleaks between devices at 30 days and 2 years, but there is no difference in sac regression. Patients with sac regression of ≥5 mm and no endoleaks in the 2-year CTA can be safely categorized for infrequent surveillance regardless of the stent graft model that has initially been used.

Long-Term Outcomes of Open Versus Endovascular Treatment for Abdominal Aortic Aneurysm: Systematic Review and Meta-Analysis With Reconstructed Time-to-Event Data

BACKGROUND

The advent of endovascular techniques has revolutionized the care of patients with uncomplicated abdominal aortic aneurysms. This analysis compares the overall survival and the freedom from reintervention rate between open surgical repair (OSR) and endovascular repair (EVAR) in patients undergoing elective abdominal aortic aneurysm (AAA) repair.

METHODS

PubMed, Scopus, and Cochrane databases were searched for studies including patients who underwent either OSR or EVAR for uncomplicated AAA. All randomized controlled trials and propensity-score-matched cohort studies reporting on the outcomes of interest were considered eligible for inclusion. The systematic search of the literature was performed by 2 independent investigators in accordance with the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. We conducted 1-stage and 2-stage meta-analyses with Kaplan-Meier-derived time-to-event data and meta-analysis with a random-effects model.

RESULTS

Thirteen studies met our eligibility criteria, incorporating 13 409 and 13 450 patients in the OSR and EVAR arms, respectively. Patients who underwent open repair had improved overall survival rates compared with those who underwent EVAR (hazard ratio [HR]=0.93, 95% confidence interval [CI]=0.88-0.98, p=0.004) during a mean follow-up of 53.8 (SD=29.8) months and this was validated by the 2-stage meta-analysis (HR=0.89, 95% CI=0.8-0.99, p=0.03, I2=62.25%). Splitting timepoint analysis suggested that EVAR offers better survival outcome compared with OSR in the first 11 months following elective intervention (HR=1.37, 95% CI=1.22-1.54, p<0.0001), while OSR offers a significant survival advantage after the 11-month timepoint and up to 180 months (HR=0.84, 95% CI=0.8-0.89, p<0.0001). Similarly, freedom from reintervention was found to be significantly better in EVAR patients (HR=1.28, 95% CI=1.14-1.44, p<0.0001) within the first 30 days. After the first month postrepair, however, OSR demonstrated higher freedom-from-reintervention rates compared with EVAR that remained significant for up to 168 months during follow-up (HR=0.73, 95% CI=0.66-0.79, p<0.0001).

CONCLUSIONS

Despite the first-year survival advantage of EVAR in patients undergoing elective AAA repair, OSR was associated with a late survival benefit and decreased risk for reintervention in long-term follow-up.

CLINICAL IMPACT

Open surgical repair for uncomplicated abdominal aortic aneurysm offers better long-term outcomes in terms of survival and freedom from reintervention rate compared to the endovascular approach but in the first year it carries a higher risk of mortality. The novelty of our study lies that instead of comparing study-level effect estimates, we analyzed reconstructed individual patient-level data. This offered us the opportunity to perform our analyses with mathematically robust and flexible survival models, which was proved to be crucial since there was evidence of different hazard over time. Our findings underline the need for additional investigation to clarify the significance of open surgical repair when compared to the latest endovascular devices and techniques within the evolving era of minimally invasive procedures.

Safety of Percutaneous Femoral Access for Endovascular Aortic Aneurysm Repair Through Previously Surgically Exposed or Repaired Femoral Arteries

OBJECTIVE

Percutaneous femoral artery access is being increasingly used in endovascular aortic repair (EVAR). The technique can be challenging in patients with previously surgically exposed or repaired femoral arteries because of excessive scar tissue. However, a successful percutaneous approach may cause less morbidity than a "re-do" open femoral approach. The aim of this study was to assess the impact of prior open surgical femoral exposure on technical success and clinical outcomes of percutaneous approach.

METHODS

This study retrospectively reviewed the clinical data of patients who underwent percutaneous EVAR between 2010 and 2020 at 2 major aortic centers. Patients were divided into 2 groups (with or without prior open surgical femoral access) for analysis of clinical outcomes. Only punctures with sheaths ≥12Fr were included for analysis. The access and (pre)closure techniques were similar in both institutions. Primary end points were intraoperative technical success, access-related revision, and access complications. A multivariate analysis was performed to identify determinants of conversion to open approach and femoral access complications in intact and re-do groins.

RESULTS

A total of 632 patients underwent percutaneous (complex) EVAR: 98 had prior open surgical femoral access and 534 patients underwent de novo femoral percutaneous access. A total of 1099 femoral artery punctures were performed: 149 in re-do and 950 in intact groins. The extent of endovascular repair included 159 infrarenal, 82 thoracic, 368 fenestrated/branched, and 23 iliac branch devices. No significant differences were seen in technical success (re-do 93.3% vs intact 95.3%, p=0.311), access-related surgical revision (0.7% vs 0.6%, p=0.950), and access complications (2.7% vs 4.0%, p=0.443). For the whole group, significant predictors for access complications in multivariate analyses were main access site (odds ratio [OR] 2.39; 95% confidence interval [CI] 1.07%-5.35%; p=0.033) and increase of the procedure time per hour (OR 1.65; 95% CI 1.34%-2.04%; p<0.001), while increase in sheath-vessel ratio had a protective effect (OR 0.33; 95% CI 0.127%-0.85%; p=0.021). Surgical conversion was predicted by main access site (OR 2.32; 95% CI 1.28%-4.19%; p=0.007) and calcification of 50% to 75% of the circumference of the access vessel (OR 3.29; 95% CI 1.38%-7.86%; p=0.005).

CONCLUSION

Within our population prior open surgical femoral artery exposure or repair had no negative impact on the technical success and clinical outcomes of percutaneous (complex) endovascular aortic aneurysm repair.

Analysis of Early Death after Elective Open Abdominal Aortic Aneurysm Repair

BACKGROUND

Mortality after open abdominal aortic aneurysm repair is a quality measure and early death may represent a technical complication or poor patient selection. Our objective was to analyze patients who died in the hospital within postoperative day (POD) 0-2 after elective abdominal aortic aneurysm repair.

METHODS

The Vascular Quality Initiative was queried from 2003-2019 for elective open abdominal aortic aneurysm repairs. Operations were categorized as in-hospital death on POD 0-2 (POD 0-2 Death), in-hospital death beyond POD 2 (POD ≥3 Death), and those alive at discharge. Univariable and multivariable analyses were performed.

RESULTS

There were 7,592 elective open abdominal aortic aneurysm repairs with 61 (0.8%) POD 0-2 Death, 156 (2.1%) POD ≥3 Death, and 7,375 (97.1%) alive at discharge. Overall, median age was 70 years and 73.6% were male. Iliac aneurysm repair and surgical approach (anterior/retroperitoneal) were similar among groups. POD 0-2 Death, compared to POD ≥3 Death and those alive at discharge, had the longest renal/visceral ischemia time, more commonly had proximal clamp placement above both renal arteries, an aortic distal anastomosis, longest operative time, and largest estimated blood loss (all P < 0.05). Postoperative vasopressor usage, myocardial infarction, stroke, and return to the operating room were most frequent in POD 0-2 Death and extubation in the operating room was least frequent (all P < 0.001). Postoperative bowel ischemia and renal failure occurred most commonly among POD ≥3 Death (all P < 0.001).On multivariable analysis, POD 0-2 Death was associated with congestive heart failure, prior peripheral vascular intervention, female sex, preoperative aspirin use, lower center volume quartile, renal/visceral ischemia time, estimated blood loss, and older age (all P < 0.05).

CONCLUSIONS

POD 0-2 Death was associated with comorbidities, center volume, renal/visceral ischemia time, and estimated blood loss. Referral to high-volume aortic centers could improve outcomes.

Predictors of Five-Year Survival after EVAR: 10-Year Experience of Single-Center Cohort Study

BACKGROUND

Endovascular abdominal aortic repair (EVAR) is the main therapeutic option for repairing abdominal aortic aneurysms (AAAs). We aimed to determine the long-term outcomes of patients who underwent EVAR at our center.

METHODS

In this retrospective cohort study, patients who underwent EVAR for intact isolated AAA at Tehran Heart Center between 2007 and 2017 were included. Clinical outcomes and the frequency of mortality were analyzed for follow-up periods. We calculated the 5-year survival rate and its predictors for our patients using Kaplan-Meier estimation.

RESULTS

We included the data of all patients (154 patients, mean age = 70.7 [± 8.0] years, 96.1% men) who successfully underwent EVAR at our center. The most common risk factors were coronary artery disease (70.1%), hypertension (68.2%), smoking (64.9%), and dyslipidemia (39.6%). There was no mortality during the procedure. The median follow-up was 65.5 months. An average decrease of 9.07 mm (95% confidence interval: 6.9-11.2) occurred in the size of the AAA. During follow-up, 12 patients developed some complications, 49 died, and 7 did not complete the follow-up. The 5-year survival rate was 75% (3.9%). The independent predictors for 5-year survival were age (hazard ratio [HR] = 1.06, P = 0.002) and anemia (HR = 1.91, P = 0.029). Despite not being statistically significant, dyslipidemia (HR = 0.573, P = 0.078) and long intensive care unit/cardiac care unit stays (HR = 1.08, P = 0.070) were borderline mortality predictors.

CONCLUSIONS

This study depicted an acceptable survival rate for patients who underwent EVAR at our center. Age and anemia, 2 modifiable predictors of 5-year survival, can probably prolong the survival rate of patients, which requires evaluation later.

Renovisceral artery alterations due to branched endovascular aortic repair and respiratory-induced deformations

OBJECTIVE

This study quantified respiratory-induced dynamics of branch vessels before and after thoracoabdominal aortic aneurysm (TAAA) branched endovascular aneurysm repair (bEVAR).

METHODS

Patients with TAAA were recruited prospectively and treated with bEVAR, predominantly with Zenith t-Branch and BeGraft Peripheral PLUS bridging stents. Using SimVascular software, three-dimensional geometric models of the vessels and implants were constructed from computed tomography angiograms during both inspiratory and expiratory breath-holds, preoperatively and postoperatively. From these models, branch take-off angles, end-stent angles (transition from distal end of stent to native artery), and curvatures were computed. Paired, two-tailed t tests were performed to compare inspiratory vs expiratory geometry and pre- vs postoperative deformations.

RESULTS

We evaluated 52 (12 celiac arteries [CA], 15 superior mesenteric arteries [SMA], and 25 renal arteries [RA]) branched renovisceral vessels with bridging stents in 15 patients. Implantation of bridging stents caused branch take-off angle to shift inferiorly in the SMA (P = .015) and RA (P = .014) and decreased the respiratory-induced branch angle motion in the CA and SMA by approximately 50%. End-stent angle increased from before to after bEVAR for the CA (P = .005), SMA (P = .020), and RA (P < .001); however, respiratory-induced deformation was unchanged. Bridging stents did not experience significant bending owing to respiration.

CONCLUSIONS

The decrease in respiratory-induced deformation of branch take-off angle from before to after bEVAR should decrease the risk of device disengagement and endoleak. The unchanging respiratory-induced end-stent bending, from before to after bEVAR, means that bEVAR maintains native vessel dynamics distal to the bridging stents. This factor minimizes the risk of tissue irritation owing to respiratory cycles, boding well for branch vessel patency. The longer bridging stent paths associated with bEVAR may enable smoother paths subject to less dynamic bending, and potentially lower fatigue risk, compared with fenestrated EVAR.

Risk factors for readmission after open abdominal aortic aneurysms repair and its outcome in chronic kidney disease patients

OBJECTIVE

Readmission after vascular procedures is a burden to hospitals and the Medicare system. Therefore, identifying risk factors leading to readmission is vital. We examined the frequency of and risk factors for 30-day readmission after open aneurysm repair (OAR) and explored post-operative outcomes with special attention for those with preexisting chronic kidney disease (CKD).

METHODS

Patients who underwent OAR were identified in the National Readmission Database (2016-2018). Demographic information and comorbidities were collected. Patients readmitted within 30 days after their index hospitalization were identified and compared to patients without readmission records.

RESULTS

A total of 5090 patients underwent OAR during the study timeframe with 488 patients (9.6%) were readmitted within 30 days. Females were more readmitted than males (F = 11.1% vs M = 9.0%, P < 0.001). Readmitted patients had more comorbidities (median ECI 12, P < 0.05), were on Medicare (73.7%, P < 0.001), had higher surgery admission cost ($146,844, P < 0.001), longer length of stay (8 days, P < 0.001), and were discharged to a lower level care facility (62.7%, P < 0.001). Comorbidities that predisposed patients for readmission include: peripheral arterial disease (OR 2.15, P < 0.01), asthma (OR 1.87, P < 0.01), chronic heart failure (OR 1.74, P < 0.05). On readmission visit, acute renal failure (23.8%) was the most common diagnosis, while intestinal surgery (13.7%) was the most common procedure. Patients with CKD (n = 968, 18.9% of total population) had double the mortality rate compared to non-CKD patients on surgery admission (10.4%, P < 0.001) and readmission (10.1%, P < 0.001).

CONCLUSION

Certain factors were noted to increase readmission rate, special attention need to be paid when dealing with such group of patients requiring OAR. Vascular surgeons should meticulously weigh benefits and risks when considering OAR in patients with CKD who are not a candidate for endovascular repair, and optimize their kidney function before considering such approach.

Severity of acute kidney injury is associated with decreased survival after fenestrated and branched endovascular aortic aneurysm repair

OBJECTIVE

Acute kidney injury (AKI) occurs frequently in complex aortic surgery and has been implicated in perioperative and long-term survival. This study sought to characterize the relationship between AKI severity and mortality after fenestrated and branched endovascular aortic aneurysm repair (F/B-EVAR).

METHODS

Consecutive patients enrolled by the US Aortic Research Consortium in 10, prospective, nonrandomized, physician-sponsored investigational device exemption studies evaluating F/B-EVAR, between 2005 and 2023, were included in this study. Perioperative AKI during hospitalization was defined by and staged using the 2012 Kidney Disease Improving Global Outcomes criteria. Determinants of AKI were evaluated with backward stepwise mixed effects multivariable ordinal logistic regression. Survival was analyzed with conditionally adjusted survival curves and backward stepwise mixed effects Cox proportional hazards modelling.

RESULTS

In the study period, 2413 patients with a median (interquartile range [IQR]) age of 74 years (IQR, 69-79 years) underwent F/B-EVAR. The median follow-up duration was 2.2 years (IQR, 0.7-3.7 years). The median baseline estimated glomerular filtration rate (eGFR) and creatinine were 68 mL/min/1.73 m2 (IQR, 53-84 mL/min/1.73 m2) and 1.1 mg/dL (IQR, 0.9-1.3 mg/dL), respectively. Stratification of AKI identified 316 patients (13%) with stage 1 injury, 42 (2%) with stage 2 injury, and 74 (3%) with stage 3 injury. Renal replacement therapy was initiated during the index hospitalization in 36 patients (1.5% of cohort, 49% of stage 3 injuries). Thirty-day major adverse events were associated with AKI severity (all P ≤ .0001). Multivariable predictors of AKI severity included baseline eGFR (proportional odds ratio, 0.9 per 10 mL/min/1.73 m2 [95% confidence interval (CI), 0.85-0.95 per 10 mL/min/1.73 m2]; P < .0001), baseline serum hematocrit (0.58 per 10% [95% CI, 0.48-0.71 per 10%]; P < .0001), renal artery technical failure during aneurysm repair (3 [95% CI,1.61-5.72]; P = .0006), and total operating time (1.05 per 10 minutes [95% CI, 1.04-1.07 per 10 minutes]; P < .0001). One-year unadjusted survivals for AKI severity strata were 91% (95% CI, 90%-92%) for no injury, 80% (95% CI, 76%-85%) for stage 1 injury, 72% (95% CI, 59-87%) for stage 2 injury, and 46% (95% CI, 35-59%) for stage 3 injury (P<.0001). Multivariable determinants of survival included AKI severity (stage 1, hazard ratio [HR], 1.6 [95% CI, 1.3-2]); stage 2, HR, 2.2 [95% CI, 1.4-3.4]); stage 3 HR, 4 [95% CI, 2.9-5.5]; P < .0001), decreased eGFR (HR, 1.1 [95% CI, 0.9-1.3]; P = .4), patient age (HR, 1.6 per 10 years [95% CI, 1.4-1.8 per 10 years]; P < .0001), baseline chronic obstructive pulmonary disease (HR, 1.5 [95% CI, 1.3-1.8]; P < .0001), baseline congestive heart failure (HR, 1.7 [95% CI, 1.6-2.1]; P < .0001), postoperative paraplegia (HR, 2.1 [95% CI, 1.1-4]; P = .02), and procedural technical success (HR, 0.6 [95% CI, 0.4-0.8]; P = .003).

CONCLUSIONS

AKI, as defined by the 2012 Kidney Disease Improving Global Outcomes criteria, occurred in 18% of patients after F/B-EVAR. Greater severity of AKI after F/B-EVAR was associated with decreased postoperative survival. The predictors of AKI severity identified in these analyses suggest a role for improved preoperative risk mitigation and staging of interventions in complex aortic repair.

Japanese single-center experience of abdominal aortic aneurysm repair over 20 years: should open or endovascular aneurysm repair be performed first?

PURPOSE

The present study analyzed the outcomes of our experience with abdominal aortic aneurysm (AAA) repair over 20 years using endovascular aortic repair (EVAR) with commercially available devices or open aortic repair (OAR) and reviewed our surgical strategy for AAA.

METHODS

From 1999 to 2019, 1077 patients (659 OAR, 418 EVAR) underwent AAA repair. The OAR and EVAR groups were compared retrospectively, and a propensity matching analysis was performed.

RESULTS

EVAR was first introduced in 2008. Our strategy was changed to an EVAR-first strategy in 2010. Beginning in 2018, this EVAR-first strategy was changed to an OAR-first strategy. After propensity matching, the overall survival in the OAR group was significantly better than that in the EVAR group at 10 years (p = 0.006). Two late deaths due to AAA rupture were identified in the EVAR group, although there were no significant differences between the OAR and EVAR groups with regard to the freedom from AAA-related death at 10 years. The rate of freedom from aortic events at 10 years was significantly higher in the OAR group than in the EVAR group (p < 0.0001).

CONCLUSION

The rates of freedom from AAA-related death in both the OAR and EVAR groups were favorable, and the rate of freedom from aortic events was significantly lower in the EVAR group than in the OAR group. Close long-term follow-up after EVAR is mandatory.

Detection of Endoleaks Following Thoracic and Abdominal Aortic Endovascular Aortic Repair-: A Comparison of Standard and Dynamic 4D-Computed Tomography Angiography

PURPOSE

Endoleaks are a common complication after endovascular aortic repair (EVAR) and thoracic endovascular aortic repair (TEVAR). The detection and correct classification of endoleaks is essential for the further treatment of affected patients. However, standard computed tomography angiography (CTA) provides no hemodynamic information on endoleaks, which can result in misclassification in complex cases. The aim of this study was to compare standard CTA (sCTA) with dynamic, dual-energy CTA (dCTA) for detection and classification of endoleaks following EVAR or TEVAR.

MATERIALS AND METHODS

This retrospective evaluation compared 69 sCTA diagnostic examinations performed on 50 different patients with 89 dCTA diagnostic examinations performed on 69 different patients.

RESULTS

In total, 15.9% of sCTA examinations and 49.4% of dCTA examinations led to the detection of endoleaks. With sCTA, 20.0% of patients were diagnosed with endoleaks, while with dCTA, 37.7% of patients were diagnosed with endoleaks. With sCTA, mainly Type 1 endoleaks were detected, whereas, with dCTA, the types of detected endoleaks were more evenly distributed. In comparison with the literature, the frequencies of endoleak types detected with dCTA better reflect the natural distribution than the frequencies detected with standard CTA.

CONCLUSION

Based on the retrospective comparative evaluation, dCTA could pose a valuable supplementary diagnostic tool resulting in a more accurate and realistic detection and classification of suspected endoleaks.

Proximal Instructions for Use Violations in Elective Endovascular Aneurysm Repair in the Vascular Quality Initiative: Retrospective Analysis

BACKGROUND

Endovascular aneurysm repair (EVAR) is often attempted in patients with marginal anatomy. These patients' midterm outcomes are available in the Vascular Quality Initiative for analysis.

STUDY DESIGN

Retrospective analysis of prospectively collected data in the Vascular Quality Initiative from patients who underwent elective infrarenal EVAR between 2011 and 2018. Each EVAR was identified as either on- or off-instructions for use (IFU) based on aortic neck criteria. Multivariable logistic regression models were used to assess associations between aneurysm sac enlargement, reintervention, and type Ia endoleak with IFU status. Kaplan-Meier time-to-event models estimated reintervention, aneurysm sac enlargement, and overall survival.

RESULTS

We identified 5,488 patients with at least 1 follow-up recorded. Those treated off-IFU included 1,236 patients ([23%] mean follow-up 401 days) compared with 4,252 (77%) treated on-IFU (mean follow-up 406 days). There was no evidence of significant differences in crude 30-day survival (96% vs 97%; p = 0.28) or estimated 2-year survival (97% vs 97%; log-rank p = 0.28). Crude type Ia endoleak frequency was greater in patients treated off IFU (2% vs 1%; p = 0.03). Off-IFU EVAR was associated with type Ia endoleak on multivariable regression model (odds ratio 1.84 [95% CI 1.23 to 2.76]; p = 0.003). Patients treated off IFU vs on IFU experienced had increased risk of reintervention within 2 years (7% vs 5%; log-rank p = 0.02), a finding consistent with results from the Cox modeling (hazard ratio 1.38 [95% CI 1.06 to 1.81]; p = 0.02).

CONCLUSIONS

Patients treated off IFU were at greater risk for type Ia endoleak and reintervention, although they had similar 2-year survival compared with those treated on IFU. Patients with anatomy outside IFU should be considered for open surgery or complex endovascular repair to reduce the probability for revision.

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

OBJECTIVE

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Endovascular aortic repair impact on myocardial contractility: A prospective study

BACKGROUND

This study aimed to estimate if the altered sphygmic wave transmission may affect the left ventricular (LV) contractile function in patients undergoing endovascular aortic repair (EVAR).

METHODS

A prospective single-centre study was carried out on consecutive patients undergoing EVAR for abdominal aortic aneurysm. A preoperative and 6-month single photon emission computed tomography (SPECT) with arterial stiffness measurement were performed to evaluate variations in pressure wave curve and myocardial perfusion parameters.

RESULTS

From 2018 to 2020 a total of 16 patients were included in the study. Among the parameters evaluated, we found a measurable reduction of the reflected wave transit time from pre- to postoperative period, for both stress (115.13 ± 7.2 ms-111.1 ± 7.0 ms, p = .08) and rest SPECT acquisitions (115.3 ± 6.2 ms-112.2 ± 5.6 ms, p = .1). Unidirectional increase of both LV end-systolic volume (34 ± 9 mL-39 ± 8 mL, p = .02) and end-diastolic volume (85 ± 34 mL-89 ± 29 mL, p = .6) was also observed. Lastly, the ratio between the end-systolic pressure and the end-systolic volume (maximal systolic myocardial stiffness) decreased from 3.6 ± 1.5 mmHg/mL to 2.66 ± .74 mmHg/mL (p = .03).

CONCLUSIONS

Our data showed that EVAR induced an altered transmission of the sphygmic wave associated with an early LV contractile impairment.

Infrarenal Abdominal Aortic Aneurysm

Abdominal aortic aneurysms are found in up to 6% of men and 1.7% of women over the age of 65 years and are usually asymptomatic. The natural history of aortic aneurysms is continued dilation leading to rupture, which is associated with an overall 80% mortality. Of the patients with ruptured aneurysms that undergo intervention, half will not survive their hospitalization. Reduction in aneurysm mortality is therefore achieved by prophylactic repair during the asymptomatic period. On a population-based level, this is supported by abdominal aortic aneurysm screening programs. Approximately 60% of abdominal aortic aneurysms are confined to the infrarenal portion of the aorta and are amenable to repair with off-the-shelf endovascular devices. Endovascular techniques have now replaced open surgery as the primary modality for aneurysm repair.

Use of the right retroperitoneum as an alternative approach to the abdominal aorta

OBJECTIVE

The left retroperitoneal approach to the aorta is a well-established technique for aortic exposure. The right retroperitoneal approach to the aorta is performed less commonly, and the outcomes remain unknown. This study aimed to evaluate the outcomes of right retroperitoneal aortic-based procedures and to determine its utility in aortic reconstruction when faced with hostile anatomy or infection in the abdomen or left flank.

METHODS

A retrospective query of a vascular surgery database from a tertiary referral center was performed for all retroperitoneal aortic procedures. Individual patient charts were reviewed, and data were collected. Demographics, indications, intraoperative details, and outcomes were tabulated.

RESULTS

From 1984 through 2020, there have been 7454 open aortic procedures; 6076 were retroperitoneal-based, and 219 of which were performed from the right retroperitoneal approach (Rrp). Aneurysmal disease was the most common indication (48.9%), and graft occlusion was the most common postoperative complication (11.4%). The average aneurysm size was 5.5 cm, and the most common reconstruction was with a bifurcated graft (77.6%). Average intraoperative blood loss was 923.8 mL (range, 50-6800 mL; median, 600 mL). Perioperative complications occurred in 56 patients (25.6%) for a total of 70 complications. Perioperative mortality occurred in two patients (0.91%). The 219 patients treated with Rrp required 66 subsequent procedures in 31 patients. These included 29 extra-anatomic bypasses, 19 thrombectomies/embolectomies, 10 bypass revisions, 5 infected graft excisions, and 3 aneurysm revisions. Eight Rrp eventually underwent a left retroperitoneal approach for aortic reconstruction. Fourteen patients with a left-sided aortic procedure required a Rrp.

CONCLUSIONS

The right retroperitoneal approach to the aorta is a useful technique in the setting of prior surgery, anatomic abnormality, or infection that complicates the use of other more frequently employed approaches. This review demonstrates comparable outcomes and the technical feasibility of this approach. The right retroperitoneal approach to aortic surgery should be considered a viable alternative to left retroperitoneal and transperitoneal access in patients with complex anatomy or prohibitive pathology for more traditional exposure.