Long-term costs to Medicare associated with endovascular and open repairs of infrarenal and complex abdominal aortic aneurysms.

OBJECTIVE: The vast majority of patients with abdominal aortic aneurysms (AAAs) undergoing repairs receive endovascular interventions (EVARs) instead of open operations (OARs). Although EVARs have better short-term outcomes, OARs have improved longer-term durability and require less radiographic follow-up and monitoring, which may have significant implications on health care economics surrounding provision of AAA care nationally. Herein, we compared costs associated with EVAR and OAR of both infrarenal and complex AAAs. METHODS: We examined patients undergoing index elective EVARs or OARs of infrarenal and complex AAAs in the 2014-2019 Vascular Quality Initiative-Vascular Implant Surveillance and Interventional Outcomes Network (VQI-VISION) dataset. We defined overall costs as the aggregated longitudinal costs associated with: (1) the index surgery; (2) reinterventions; and (3) imaging tests. We evaluated overall costs up to 5 years after infrarenal AAA repair and 3 years for complex AAA repair. Multivariable regressions adjusted for case-mix when evaluating cost differences between EVARs vs OARs. RESULTS: We identified 23,746 infrarenal AAA repairs (8.7% OAR, 91% EVAR) and 2279 complex AAA repairs (69% OAR, 31% EVAR). In both cohorts, patients undergoing EVARs were more likely to be older and have more comorbidities. The cost for the index procedure for EVARs relative to OARs was lower for infrarenal AAAs ($32,440 vs $37,488; P < .01) but higher among complex AAAs ($48,870 vs $44,530; P < .01). EVARs had higher annual imaging and reintervention costs during each of the 5 postoperative years for infrarenal aneurysms and the 3 postoperative years for complex aneurysms. Among patients undergoing infrarenal AAA repairs who survived 5 years, the total 5-year cost of EVARs was similar to that of OARs ($35,858 vs $34,212; -$223 [95% confidence interval (CI), -$3042 to $2596]). For complex AAA repairs, the total cost at 3 years of EVARs was greater than OARs ($64,492 vs $42,212; +$9860 [95% CI, $5835-$13,885]). For patients receiving EVARs for complex aneurysms, physician-modified endovascular grafts had higher index procedure costs ($55,835 vs $47,064; P < .01) although similar total costs on adjusted analyses (+$1856 [95% CI, -$7997 to $11,710]; P = .70) relative to Zenith fenestrated endovascular grafts among those that were alive at 3 years. CONCLUSIONS: Longer-term costs associated with EVARs are lower for infrarenal AAAs but higher for complex AAAs relative to OARs, driven by reintervention and imaging costs. Further analyses to characterize the financial viability of EVARs for both infrarenal and complex AAAs should evaluate hospital margins and anticipated changes in costs of devices.

National trends in utilization of surgeon-modified grafts for complex and thoracoabdominal aortic aneurysms.

INTRODUCTION: Custom-branched/fenestrated grafts are widely available in other countries, but in the United States, they are limited to a handful of centers, with the exception of a 3-vessel juxtarenal device (ZFEN). Consequently, many surgeons have turned to alternative strategies such as physician-modified endografts (PMEGs). We therefore sought to determine how widespread the use of these grafts is. METHODS: We studied all complex endovascular repairs of complex and thoracoabdominal aortic aneurysms in the Vascular Quality Initiative from 2014 to 2022 to examine temporal trends. RESULTS: A total of 5826 repairs were performed during the study period: 1895 ZFEN, 3241 PMEG, 595 parallel grafting, and 95 where parallel grafting was used in addition to ZFEN, with a mean of 2.7 ± 0.98 vessels incorporated. Over time, the number of PMEGs steadily increased, both overall and for juxtarenal aneurysms, whereas the number of ZFENs essentially leveled off by 2017 and has remained steady ever since. In the most recent complete year (2021), PMEGs outnumbered ZFENs by over 2:1 overall (567 to 256) and nearly twofold for juxtarenal repairs. In three-vessel cases involving juxtarenal aneurysms, PMEGs were used as frequently as ZFENs (43% vs 43%), whereas the proportion of juxtarenal aneurysms repaired using a four-vessel graft configuration increased from 20% in 2014 to 29% in 2021 (P < .001). The differences in PMEG use were more pronounced as surgeon volume increased. Surgeons in the lowest quartile of volume performed <2 complex repairs annually, evenly split between PMEGs and ZFENs. However, surgeons in the highest quartile of volume performed a median of 18 (interquartile range: 10-21) PMEGs/y, but only 1.6 (interquartile range: 0.8-3.4) ZFENs/y. The number of physician-sponsored investigational device exemption trials of PMEGs has expanded from 1 in 2012 to 8 currently enrolling. As those data are not included in the Vascular Quality Initiative, the true number of PMEGs is likely substantially higher. CONCLUSIONS: PMEGs have become the dominant endovascular repair modality of complex abdominal and thoracoabdominal aortic aneurysms outside of investigational device exemptions. The field of endovascular aortic surgery and patients with complex aneurysms would benefit from broader publication of PMEG techniques, outcomes, and comparisons to custom-manufactured grafts.

Utility of structured follow-up imaging after aortic surgery.

BACKGROUND: Although postoperative follow-up after aortic surgery is recommended by guidelines, its clinical utility is not well documented. We hypothesized that structured follow-up imaging by an aortic program would improve outcomes. We then documented radiologic findings on asymptomatic postoperative imaging. METHODS: All patients who survived to discharge after open thoracic aortic surgery between January 2017 and July 2021 were included, excluding endocarditis. Patients who followed at our center and received scheduled imaging were compared with patients who did not. Survival was analyzed by the method of Kaplan-Meier, and reintervention was assessed using the Fine-Gray subhazard function. Routine imaging was reviewed for aortic growth, pseudoaneurysm, and perigraft density. RESULTS: After aortic surgery, the cumulative incidence of follow-up was 38.6% at 3 years postoperatively. Patients with follow-up were more likely to have a dissection and fewer comorbidities but were similar in regards to socioeconomic factors and distance to hospital. After matching and accounting for immortal time bias, patients with follow-up had a greater reintervention rate (26.0% vs 9.0%) with similar survival (98.7% vs 95.2%, P = .110) at 4 years. The cumulative incidence of pseudoaneurysm, significant perigraft density, and growth ≥3 mm/year on routine imaging was 49.7% at 3 years. CONCLUSIONS: Implementation of structured follow-up imaging by an aortic program resulted in low clinical compliance. Follow-up was associated with increased rates of aortic reintervention. Clinically relevant radiologic findings were common on asymptomatic imaging and increased throughout 5-year follow-up rather than plateauing in the early postoperative period.

Editor's Choice -- Age Stratified Midterm Survival Following Endovascular Versus Open Repair of Juxtarenal Abdominal Aortic Aneurysms.

OBJECTIVE: Age stratified mortality was examined following fenestrated endovascular aneurysm repair (F-EVAR) vs. open repair of juxtarenal abdominal aortic aneurysms (AAAs) METHODS: All patients undergoing first time elective F-EVAR and complex open aneurysm repair (c-OAR) for juxtarenal AAA in the Vascular Quality Initiative between 2014 and 2021 were identified. Open repairs were compared with commercially available fenestrated endovascular aneurysm repair and physician modified endografts (PMEGs). Patients were stratified into three age groups (< 65, 65 - 75, > 75 years). Primary outcomes were peri-operative and five year mortality, and inverse probability weighted risk adjustment was performed to account for baseline differences. RESULTS: Overall, 1 961 patients underwent F-EVAR (82% commercial F-EVAR, 18% PMEG) and 3 385 patients underwent c-OAR. Across age groups, the distribution of F-EVAR (vs. c-OAR) was: < 65 years: 23%, 65 - 75 years: 33%, > 75 years: 52%. After adjustment, among patients < 65 years, compared with c-OAR, F-EVAR was associated with similar peri-operative mortality (0.9% vs. 2.1%; hazard ratio [HR] 0.40, 95% confidence interval [CI] 0.07 - 1.44], p = .22), and five year mortality (13% vs. 9.5%; HR 1.44, 95% CI 0.71 - 2.90, p = .31). Among patients aged 65 - 75 years, between juxtarenal AAA repair modalities, compared with c-OAR, F-EVAR was associated with a significantly lower risk of peri-operative mortality (2.2% vs. 5.0%; HR 0.50, 95% CI 0.30 - 0.79, p = .004), and five year mortality (13% vs. 13%; HR 0.94, 95% CI 0.65 - 1.36, p = .74). Similarly, among patients > 75 years, compared with c-OAR, F-EVAR was associated with lower peri-operative mortality (2.2% vs. 6.5%; HR 0.26, 95% CI 0.13 - 0.47, p < .001), but with similar five year mortality (18% vs. 21%; HR 0.83, 95% CI 0.57 - 1.20, p = .31). CONCLUSION: Among patients with a juxtarenal AAA, F-EVAR was associated with a lower peri-operative mortality compared with c-OAR in patients ≥ 65 years, but was similar in those < 65 years. At five years, F-EVAR was associated with similar mortality in all age groups, though there was a non-significant trend for a higher mortality rate in younger patients.

One-year aneurysm-sac dynamics are associated with reinterventions and rupture following infrarenal endovascular aneurysm repair.

OBJECTIVE: One-year aneurysm sac changes have previously been found to be associated with mortality and may have the potential to guide personalized follow-up following endovascular aneurysm repair (EVAR). In this study, we examined the association of these early sac changes with long-term reintervention and rupture. METHODS: We identified all patients undergoing first-time EVAR for intact abdominal aortic aneurysm between 2003 and 2018 in the Vascular Quality Initiative with linkage to Medicare claims for long-term outcomes. We included patients with an imaging study at 1 year postoperatively. Aneurysm sac behavior was defined as per the Society for Vascular Surgery guidelines: stable sac (<5 mm change), sac regression (≥5 mm), and sac expansion (≥5 mm). Outcomes included mortality, reintervention, and rupture within 8 years, which were assessed with Kaplan-Meier methods and multivariable Cox regression analysis. Secondarily, we utilized polynomial spline interpolation to demonstrate the continuous relationship of diameter change to 8-year hazard of reintervention, rupture, or mortality as a composite outcome. RESULTS: Of 31,185 EVAR patients, 16,102 (52%) had an imaging study at 1 year and were included in this study. At 1 year, 44% of sacs remained stable, 49% regressed, and 6.2% displayed expansion. Following risk adjustment, compared with a stable sac at 1 year, sac regression was associated with lower 8-year mortality (49% vs 53%; hazard ratio [HR], 0.92; 95% confidence interval [CI], 0.85-0.99; P = .036), reintervention rate (8.9% vs 15%; HR, 0.58; 95% CI, 0.50-0.68; P < .001), and rupture rate (2.0% vs 4.0%; HR, 0.45; 95%CI, 0.29-0.69; P < .001). Conversely, compared with a stable sac, sac expansion was associated with higher 8-year mortality (64% vs 53%; HR, 1.31; 95% CI, 1.14-1.51; P < .001) and reintervention rate (27% vs 15%; HR, 1.98; 95% CI, 1.57-2.51; P < .001), but similar risk of rupture (7.2% vs 4.0%; HR, 1.61; 95% CI, 0.88-2.96; P = .12). Polynomial spline interpolation demonstrated that, compared with no diameter change at 1 year, increased sac regression was associated with an incrementally lower risk of late outcomes, whereas increased sac expansion was associated with an incrementally higher risk of late outcomes. CONCLUSIONS: Following EVAR, compared with a stable sac at 1-year imaging, sac regression and expansion are associated with a lower and higher risk respectively of long-term mortality, reinterventions, and ruptures. Moreover, the amount of regression or expansion seems to be incrementally associated with these late outcomes, too. Future studies are needed to determine how to improve 1-year sac regression, and whether it is safe to extend follow-up intervals for patients with regressing sacs.

Outcomes of Staged Repairs of Complex Endovascular Repairs of Thoracoabdominal Aortic Aneurysms.

BACKGROUND: Endovascular treatment allows for the staging of thoracoabdominal aortic aneurysm repairs (eTAAAs) in an effort to decrease the risk of spinal cord ischemia (SCI), but data are limited. METHODS: We studied all eTAAAs in the Vascular Quality Initiative from 2014 to 2021. Inverse probability weighting was used to compare perioperative and long-term outcomes of staged and single-stage repairs. Thoracoabdominal life-altering events (TALEs) are the composite endpoint consisting of death/stroke/permanent SCI/permanent dialysis. RESULTS: There were 3,258 total operations during the study period. In total, 841 cases (26%) were staged repairs, and 2,417 (74%) were completed in a single stage, but in the cohort of patients with extensive aneurysms, 44% were staged. Staging methods included thoracic endograft (78%), branch (23%), and iliac (5%). Staged repairs were more often employed by high-volume surgeons at high-volume centers; for larger, more extensive aneurysms, with higher rates of prior aortic surgery. After adjustment, staged repair and single-stage treatment were associated with similar odds of all perioperative outcomes and including mortality, TALE, acute kidney injury, stroke, dialysis, and SCI, as well as long-term survival. This was consistent in the subgroups of patients with extensive aneurysms undergoing elective procedures. Of note, first-stage thoracic endografts were associated with 2.6% mortality, 7.3% TALE, 1.5% dialysis, and 4.1% SCI, and 25% of patients did not undergo a second stage. First-stage procedures accounted for one-third of perioperative complications including half of the deaths in the staged cohort. CONCLUSIONS: Staged eTAAA repairs were associated with similar perioperative and long-term complications to single-stage treatments. However, first stage procedures are associated with significant morbidity and mortality, and one-quarter of patients never complete their repairs. These data demonstrate the necessity of evaluating the outcomes of all patients planned for staged procedures, not only those who make it to the final stage. More data are needed as to the optimal method of spinal cord protection for these challenging aneurysms.

Low-volume surgeons can have better outcomes at certain hospital settings for open abdominal aortic repairs.

OBJECTIVE: The volume-outcomes relationship is cross-cutting among open abdominal aortic operations, where higher-volume surgeons have better perioperative outcomes. However, there has been minimal focus on low-volume surgeons and how to improve their outcomes. This study sought to identify if there are any differences in outcomes among low-volume surgeons for open abdominal aortic surgeries by different hospital settings. METHODS: We used the 2012-2019 Vascular Quality Initiative registry to identify all patients who underwent open abdominal aortic surgery for aneurysmal or aorto-iliac occlusive disease by a low-volume surgeon (<7 operations annually). We categorized high-volume hospitals using three distinct definitions: those that performed ≥10 operations annually, those with at least one high-volume surgeon, and by the number of surgeons (1-2 surgeons, 3-4 surgeons, 5-7 surgeons, and 8+ surgeons). Outcomes included 30-day perioperative mortality, overall complications, and failure-to-rescue. We compared outcomes among low-volume surgeons using univariable and multivariable logistic regressions across each of these three hospital categorizations. RESULTS: Among 14,110 patients who underwent open abdominal aortic surgery, 10,252 (7 3%) were performed by 1155 low-volume surgeons. Two-thirds of these patients (66%) underwent their surgery at a high-volume hospital, fewer than one-third (30%) at a hospital that had at least one high-volume surgeon, and one-half (49%) at hospitals with at least five surgeons. Among all patients operated on by low-volume surgeons, rates of 30-day mortality were 3.8%, perioperative complications were 35.3%, and failure-to-rescue were 9.9%. Low-volume surgeons operating at high-volume hospitals for aneurysmal disease had lower rates of perioperative death (adjusted odds ratio [aOR], 0.66; 95% confidence interval [CI], 0.48-0.90) and failure-to-rescue (aOR, 0.70; 95% CI, 0.50-0.98), but similar rates of complications (aOR, 1.06; 95% CI, 0.89-1.27). Similarly, patients undergoing their operation at hospitals that had at least one high-volume surgeon had lower rates of death (aOR, 0.71; 95% CI, 0.50-0.99) for aneurysmal disease. Patient outcomes among low-volume surgeons for aorto-iliac occlusive disease did not vary by hospital setting. CONCLUSIONS: The majority of patients undergoing open abdominal aortic surgery have a low-volume surgeon, where outcomes are slightly better for those taking place at a high-volume hospital. Focused and incentivized interventions may be needed to improve outcomes among low-volume surgeons across all practice settings.

Thoracoabdominal aortic aneurysm life-altering events following endovascular aortic repair in the Vascular Quality Initiative.

OBJECTIVE: Endovascular aortic aneurysm repair (EVAR) has lower rates of postoperative mortality and morbidity when compared with open repair. However, endovascular repair still carries the risk of postoperative dialysis, paralysis, and stroke. This study examined the rates of postoperative mortality and morbidity stratified by type of endovascular aortic aneurysm repair. METHODS: All patients who underwent EVAR in the Vascular Quality Initiative registry from January 2011 to May 2022 were identified. Patients were stratified by repair type: infrarenal EVAR, complex EVAR, thoracic endovascular aortic repair (TEVAR), extent I to III thoracoabdominal aortic aneurysm (TAAA) repair, or aortic arch repair. The primary outcome was postoperative thoracoabdominal aortic aneurysm life-altering events (TALE) across the different treatment groups. TALE was defined as a composite outcome of postoperative mortality, dialysis, paralysis, and/or stroke. Mixed effect logistic regression modeling was used to identify procedural and anatomic factors that were independently associated with TALE. RESULTS: A total of 52,592 EVARs, 3768 complex EVARs, 3899 TEVARs, 1139 extent I to III TAAA repairs, and 479 arch repairs were identified. TALE was observed in 1.2% of EVARs, 4.8% of complex EVARs, 6.0% of TEVARs, 10% of extent I to III TAAA repairs, and 14% of arch repairs. More proximal landing zone was associated with higher odds of TALE after complex EVAR (odds ratio [OR], 1.9; 95% confidence interval [CI], 1.2-3.1; P = .008), TEVAR (OR, 2.2; 95% CI, 1.4-3.5; P = .001), and extent I to III TAAA repair (OR, 2.7; 95% CI, 1.5-4.9; P = .001). Aortic diameter >65 mm was associated with higher odds of TALE after infrarenal EVAR (OR, 1.8; 95% CI, 1.4-2.3; P < .001), complex EVAR (OR, 1.6; 95% CI, 1.1-2.3; P = .010), TEVAR (OR, 2.7; 95% CI, 2.0-3.8; P < .001), and arch repair (OR, 2.4; 95% CI, 1.3-4.4; P = .007). The use of parallel grafting technique (chimney/snorkel/periscope) during extent I to III TAAA repair was also associated with higher odds of TALE (OR, 1.8; 95% CI, 1.1-3.2; P = .032). Preoperative chronic kidney disease was also associated with higher odds of TALE after infrarenal EVAR (OR, 4.3; 95% CI, 3.0-5.7; P < .001), complex EVAR (OR, 5.2; 95% CI, 3.3-8.2; P < .001), TEVAR (OR, 4.5; 95% CI, 2.8-7.1; P < .001), and extent I to III TAAA repair (OR, 3.2; 95% CI, 1.6-6.7; P = .001). CONCLUSIONS: Although TALE was originally described for TAAA repairs, TALE may occur after complex EVAR, TEVAR, and arch repairs as well. Therefore, TALE and its component parts should be used to evaluate the efficacy of all aortic repairs and for preoperative counseling. Additionally, surgeons should be aware of anatomic and procedural characteristics that are associated with higher odds of TALE. The anticipated need for such interventions during aortic repair should be factored into preoperative risk assessment of patients.

Outcomes of Complex Endovascular Treatment of Post-Dissection Aneurysms.

OBJECTIVE: Reports of endovascular treatment of chronic post-dissection aneurysms are limited to high volumes centres, posing questions about generalisability. METHODS: All endovascular repairs of intact pararenal and thoraco-abdominal aneurysms in the Vascular Quality Initiative from 2014 to 2021 were studied, and peri-operative and long term outcomes were compared between repairs of degenerative and post-dissection aneurysms. Peri-operative outcomes were compared using mixed effects logistic regression, and long term outcomes using Medicare linkage. RESULTS: There were 123 patients who completed treatment for post-dissection aneurysms and 3 635 for degenerative aneurysms, with 36% of post-dissection repairs and 6.7% of degenerative repairs performed in a staged fashion (p < .001). The majority (84%) of post-dissection aneurysms were extensive thoraco-abdominal aneurysms (TAAAs: Crawford Type 1, 2, 3, 5), compared with 22% of degenerative aneurysms (p < .001). Physician modified endografts were the primary repair type for post-dissection (73%), while commercially available fenestrated grafts were the dominant repair for degenerative (48%). The first stage of staged procedures was associated with a 2.8% peri-operative mortality rate, 5.1% spinal cord ischaemia, and 8.9% thoraco-abdominal life altering events (the composite of peri-operative death, stroke, permanent spinal cord ischaemia, and dialysis). Th final stage procedure and fluoroscopy times were similar, but technical success was lower in post-dissection repairs (75% vs. 83%, p = .018), both due to issues with the main endograft or bridging vessels (11% vs. 6.6%, p = .055), and types 1and 3 endoleak at completion (17% vs. 10%, p = .035). In addition, high volume surgeons had two fold higher odds of technical success than their low volume counterparts. Adjusted peri-operative outcomes were similar between pathology types, including when comparisons were restricted to extensive TAAAs. Crude and adjusted three year survival were similar, but three year re-interventions were significantly higher following post-dissection repairs (p < .001). CONCLUSION: Complex endovascular repair of chronic post-dissection aneurysms is feasible but is associated with high rates of re-interventions and non-trivial rates of lack of technical success. More data are needed to evaluate the long term durability of these procedures, and the utility of centralising these complex procedures.

Asian race is associated with peripheral arterial disease severity and postoperative outcomes.

OBJECTIVE: The nature of peripheral arterial disease and postoperative outcomes are understudied in Asian patients. We aimed to determine if there are disparities in disease severity at the time of presentation and postoperative outcomes with regard to Asian race. METHODS: We analyzed the Society for Vascular Surgery Vascular Quality Initiative Peripheral Vascular Intervention dataset from 2017 to 2021, which includes endovascular lower extremity interventions. Propensity scores were used to match White and Asian patients based on age, sex, comorbidities, ambulatory/functional status, and intervention level. Differences were examined with regard to Asian race across all patients in the United States, Canada, and Singapore, and separately in the United States and Canada only. The primary outcome was emergent intervention. We also examined differences in severity of disease and postoperative outcomes. RESULTS: A total of 80,312 White and 1689 Asian patients underwent peripheral vascular intervention. After propensity score matching, we identified 1669 matched pairs of patients across all centers including Singapore and 1072 matched pairs in the United States and Canada only. Among the matched cohort consisting of all centers, Asian patients had a higher rate of emergent intervention to prevent limb loss (5.6% vs 1.7%, P < .001). The majority of Asian patients presented with chronic limb threatening ischemia at a higher rate than White patients within the cohort including Singapore (71% vs 66%, P = .005). Within both propensity-matched cohorts, the rate of in-hospital death was higher in Asian patients (all centers: 3.1% vs 1.2%, P < .001; United States and Canada only: 2.1% vs 0.8%, P = .010). Logistic regression demonstrated greater odds of emergent intervention in Asian patients from all centers including Singapore (odds ratio [OR], 3.3; 95% confidence interval [CI], 2.2-5.1, P < .001) but not in the United States and Canada only (OR, 1.4; 95% CI, 0.8-2.8, P = .261). In addition, Asian patients had greater odds of in-hospital death in both matched cohorts (all centers: OR, 2.6; 95% CI, 1.5-4.4, P < .001; United States and Canada: OR, 2.5; 95% CI, 1.1-5.8, P = .026). Asian race was associated with a greater risk of loss of primary patency at 18 months (all centers: hazard ratio, 1.5; CI, 1.2-1.8, P = .001; United States and Canada only: hazard ratio, 1.5; CI, 1.2-1.9, P = .002). CONCLUSIONS: Asian patients are more likely to present with advanced peripheral arterial disease and undergo emergent intervention to prevent limb loss, in addition to having worse postoperative outcomes and long-term patency. These results highlight the need for improved screening and postoperative follow-up in this understudied population.

Mortality analysis of endovascular aneurysm sealing versus endovascular aneurysm repair.

BACKGROUND: Endovascular aneurysm sealing (EVAS), using the Nellix endovascular aneurysm sealing system, has been associated with high reintervention and migration rates. However, prior reports have suggested that EVAS might be related to a lower all-cause mortality compared with endovascular aneurysm repair (EVAR). In the present study, we examined the 5-year all-cause mortality trends after EVAS and EVAR. METHODS: We compared the 333 EVAS patients in the EVAS-1 Nellix U.S. investigational device exemption trial with 16,497 infrarenal EVAR controls from the Vascular Quality Initiative, treated between 2014 and 2016, after applying the exclusion criteria from the investigational device exemption trial (ie, hemodialysis, creatinine >2.0 mg/dL, rupture). As a secondary analysis, we stratified the patients by aneurysm diameter (<5.5 cm and ≥5.5 cm). We calculated propensity scores after adjusting for demographics, comorbidities, and anatomic characteristics and applied inverse probability weighting to compare the risk-adjusted long-term mortality using Kaplan-Meier and Cox regression analyses. RESULTS: After weighting, the EVAS group had experienced similar 5-year mortality compared with the controls from the Vascular Quality Initiative (EVAS vs EVAR, 18% vs 14%; hazard ratio [HR], 1.1; 95% confidence interval [CI], 0.71-1.7; P = .70). The subgroup analysis demonstrated that for patients with an aneurysm diameter of <5.5 cm, EVAS was associated with higher 5-year mortality compared with EVAR (19% vs 11%; HR, 2.4; 95% CI, 1.7-4.7; P = .013). In patients with an aneurysm diameter of ≥5.5 cm, EVAS was associated with lower mortality within the first 2 years (2-year mortality: HR, 0.29; 95% CI, 0.13-0.62; P = .002). However, compared with EVAR, EVAS was associated with higher mortality between 2 and 5 years (HR, 1.9; 95% CI, 1.2-3.0; P = .005), with no mortality difference at 5 years (18% vs 17%; HR, 0.82; 95% CI, 0.4-1.4; P = .46). CONCLUSIONS: Within the overall population, EVAS was associated with similar 5-year mortality compared with EVAR. EVAS was associated with higher mortality for those with small aneurysms (<5.5 cm). For those with larger aneurysms (≥5.5 cm), EVAS was initially associated with lower mortality within the first 2 years, although this advantage was lost thereafter, with higher mortality after 2 years. Future studies are required to evaluate the specific causes of death and to elucidate the potential beneficial mechanism behind sac obliteration that leads to this potential initial survival benefit. This could help guide the development of future grafts with better proximal fixation and sealing that also incorporate sac obliteration.

Racial disparities in treatment of ruptured abdominal aortic aneurysms.

OBJECTIVE: The Society for Vascular Surgery has recommended immediate transfer of patients with ruptured abdominal aortic aneurysms (rAAAs) to a regional center when feasible. However, Black patients might be less likely to be transferred and more likely to be turned down for repair. We, therefore, examined the transfer rates, turndown rates, and outcomes for Black vs White patients presenting with rAAAs in two large databases. METHODS: We examined all rAAA repairs in the Vascular Quality Initiative from 2003 to 2020 to evaluate the transfer rates and outcomes for Black vs White patients. We used the National Inpatient Sample from 2004 to 2015 to examine the turndown rates. Mixed effects logistic regression, Cox regression, and marginal effects modeling were used to study the interaction between race, insurance status, surgery type (open repair vs endovascular aortic aneurysm repair), and hospital volume. RESULTS: We identified 4935 patients with rAAAs in the Vascular Quality Initiative (6.2% Black) and 48,489 in the National Inpatient Sample (6.0% Black). The rates of transfer were high; however, Black patients were significantly less likely to undergo transfer before repair compared with White patients (49% Black vs 62% White; P = .002). The result was consistent in both crude and adjusted analyses when considering only stable patients and was not modified by insurance status, surgery type, or hospital volume. No significant differences were found in perioperative mortality (22% vs 26%; P = .098) or complications (52% vs 52%; P = .64). However, Black patients were significantly more likely to be turned down for repair (37% vs 28%; odds ratio, 1.5; 95% confidence interval, 1.2-1.9; P < .001). A significant interaction was found between race and insurance status with respect to turndown. Patients with private insurance had undergone surgery at a similar rate, regardless of race. However, among patients with Medicare or Medicaid/self-pay, Black patients were less likely than were White patients to undergo repair (Medicare, 64% vs 72%; P = .001; Medicaid/self-pay, 43% vs 61%; P = .031). Patients with Medicaid/self-pay were also less likely to undergo repair than were patients of the same race with either Medicare or private insurance (P < .05). CONCLUSIONS: We found that Black patients with rAAAs are poorly served by the current systems of interhospital transfer in the United States, because they less often undergo transfer before repair. Although the postoperative outcomes appeared similar, this finding could be falsely optimistic, because Black patients, especially the underinsured, were turned down for repair more often even after adjustment. Significant work is needed to better understand the reasons underlying these disparities and identify the targets to improve the care of Black patients with rAAAs.

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

OBJECTIVE: Vulnerable populations, including women and racial and ethnic minorities, have been historically underrepresented in clinical trials. We, therefore, studied the demographics of patients enrolled in pivotal endovascular aortic device trials in the United States. METHODS: We queried the Food and Drug Administration (FDA) medical devices database for all FDA-approved endografts for the treatment of aortic aneurysms, transections, and dissections from September 1999 to November 2021. These included abdominal endovascular aortic repair (EVAR), thoracic EVAR (TEVAR), fenestrated EVAR (FEVAR) devices, and dissection stents. Multiple cases of approval for expanded indications were included separately. The primary outcomes included the proportion of trials reporting participant sex, race, and ethnicity and the proportion of enrolled participants across sex, racial, and ethnic groups. RESULTS: The FDA provided 29 approvals from 29 trials of 24 devices: 15 EVAR devices (52%), 12 TEVAR devices (41%), 1 FEVAR device (3.4%), and 1 dissection stent (3.4%). These trials had included 4046 patients. Of the 29 trials, all had reported on the sex of the participants, and the median female enrollment was 21% (interquartile range [IQR], 11%-34%). The EVAR trials had the lowest female enrollment (11%; IQR, 8.7%-13%) compared with 41% (IQR, 27%-45%) in the TEVAR trials, 21% in the FEVAR trial, and 34% in the dissection stent trial (P < .01 for the difference). Only 52% of the trials had reported the three most common racial groups (White, Black, Asian), and only 48% had reported Hispanic ethnicity. The TEVAR trials were the most likely to report all three racial groups and Hispanic ethnicity (92% and 75%, respectively), while the EVAR trials had the lowest reporting rates (13% and 20%, respectively). Where reported, the median enrollment of racial and ethnic groups across the trials was as follows: Black patients, 9.8% (FEVAR, 0%; EVAR, 1.9%; TEVAR, 12%; dissection stent, 25%; P = .01); Asian patients, 2.4% (EVAR, 0.6%; FEVAR, 2.4%; TEVAR, 2.5%; dissection stent, 11%; P = .24); and Hispanic patients, 3.8% (EVAR, 1.3%; FEVAR, 2.4%; TEVAR, 3.9%; dissection stent, 4.1%; P = .75). CONCLUSIONS: Racial and ethnic minority groups were underrepresented and underreported in pivotal aortic device trials that led to FDA approval. Female patients were also underrepresented in these aortic trials, especially for EVAR. These data suggest the need for standardization of reporting practices and minimum thresholds for minority and female participation in pivotal trials to promote equitable representation.

The association between device instructions for use adherence and outcomes after elective endovascular aortic abdominal aneurysm repair.

OBJECTIVE: Aortic neck anatomy has a significant impact on the complexity of endovascular aortic aneurysm repair (EVAR), with concern that neck characteristics outside of the instructions for use (IFU) may result in worse outcomes. Therefore, this study determined the impact of neck characteristics outside of the IFU on perioperative and 1-year outcomes and mid-term survival after EVAR. METHODS: We identified all patients undergoing elective infrarenal EVAR from December 2014 to May 2020 in the Vascular Quality Initiative database. Neck characteristics outside of the IFU were determined based the specific device IFU neck characteristics (neck diameter, length, and angulation). Patients without 1-year follow-up were excluded for the 1-year outcomes analyses (n = 6138 [40%]). We used multivariable adjusted logistic regression and Cox proportional hazard models to identify the independent associations between neck characteristics outside of the IFU and our outcomes. RESULTS: Of the 15,448 patients identified, 22.1% had neck characteristics outside of the IFU, including 6.6% with a infrarenal angle, 6.8% with a neck length, 10.4% with a neck diameter, and 1.1% with a suprarenal angulation outside of the IFU. Of these, 2.4% had more than one neck characteristic outside of the IFU. Patients with neck characteristics outside of the IFU were more often female (27.9% vs 15.0%; P < .001) and were older (median age, 75 years vs 73 years; P < .001). EVAR patients with neck characteristics outside of the IFU had higher rates of type Ia endoleaks at completion (4.8% vs 2.5%; P < .001), perioperative mortality (1.2% vs 0.6%; P < .001), 1-year sac expansion (7.1% vs 5.3%; P = .017), and 1-year reinterventions (4.4% vs 3.2%; P = .03). In multivariable adjusted analyses, neck characteristics outside of the IFU were independently associated with type Ia completion endoleaks (OR, 1.6; 95% CI, 1.3-2.0; P < .001), perioperative mortality (OR, 1.8; 95% CI, 1.2-2.7; P = .005), 1-year sac expansion (OR, 1.4; 95% CI, 1.0-1.8; P = .025), and 1-year reinterventions (OR, 1.4; 95% CI, 1.0-1.9; P = .039). The unadjusted midterm survival was lower for patients with neck characteristics outside of the IFU than for patients without (5-year survival 84.0% vs 86.7%; log-rank P < .001). However, after adjustment, survival was similar for patients with neck characteristics outside of the IFU to those within (hazard ratio, 1.1; 95% CI, 1.0-1.3; P = .22). CONCLUSIONS: Neck characteristics outside of the IFU are independently associated with completion type Ia endoleaks, perioperative mortality, 1-year sac expansion, and 1-year reinterventions among patients undergoing elective EVAR. These results indicate that continued effort is needed to improve the proximal seal in patients with neck characteristics outside of the IFU undergoing EVAR. Also, in patients with severe hostile neck characteristics, alternative approaches such as open repair, use of a fenestrated or branched device, or endoanchors should be considered.

Evaluating proximal clamp site and intraoperative ischemia time among open repair of juxtarenal aneurysms.

BACKGROUND: The proportion of open aneurysm repairs requiring at least a suprarenal clamp has increased in the past few decades, partly owing to preferred endovascular approaches for most patients with infrarenal aneurysms, suggesting that the management of aortic clamp placement has become even more relevant. This study evaluated the association between the proximal clamp site and intraoperative ischemia times with postoperative renal dysfunction and mortality. METHODS: We used the Vascular Quality Initiative to identify all patients undergoing open repairs of elective or symptomatic juxtarenal AAAs from 2004 to 2018 and compared outcomes by clamp site: above one renal artery, above both renal arteries (suprarenal), or above the celiac trunk (supraceliac). Outcomes evaluated included acute kidney injury (AKI), new-onset renal failure requiring renal replacement therapy (RRT), 30-day mortality, and 1-year mortality. We used multilevel logistic regressions and Cox proportional hazards models, clustered at the hospital level, to adjust for confounding. RESULTS: We identified 3976 patients (median age, 71 years; 70% male; 8.2% non-Caucasian), with a median aneurysm diameter of 5.9cm (interquartile range [IQR], 5.4-6.8 cm). Proximal clamp sites were above one renal artery (31%), suprarenal (52%), or supraceliac (17%). The rates of unadjusted outcomes were 20.5% for AKI, 4.1% for new-onset RRT, 4.9% for 30-day mortality, and 8.3% for 1-year mortality. On adjusted analyses, independent of ischemia time, suprarenal clamping relative to clamping above a single renal artery had higher odds of postoperative AKI (adjusted odds ratio [aOR], 1.50; 95% confidence interval; 95% CI, CI, 1.28-1.75), but similar odds for new-onset RRT (aOR, 1.27; 95% CI, 0.79-2.06) and 30-day mortality (aOR, 1.12; 95% CI, 0.79-1.58) and hazards for 1-year mortality (adjusted hazard ratio, 1.12; 95% CI, 0.86-1.45). However, every 10 minutes of prolonged intraoperative ischemia time was associated with an increase in odds or hazards ratio of postoperative AKI by 7% (IQR, 3%-11%), new-onset RRT by 11% (IQR, 4%-17%), 30-day mortality by 11% (IQR, 6%-17%), and 1-year mortality by 7% (IQR, 2%-13%). Patients with more than 40 minutes of ischemia time had notably higher rates of all four outcomes. CONCLUSIONS: Suprarenal clamping relative to clamping above a single renal artery was associated with AKI, but not new-onset RRT or 30-day mortality. However, the intraoperative renal ischemia time was independently associated with all four postoperative outcomes. Although further studies are warranted, our findings suggest that an expeditious proximal anastomosis creation is more important than trying to maintain clamp position below one renal artery, suggesting that suprarenal clamping may be the best strategy for open AAA repair when needed to efficiently perform the proximal anastomosis.

Overview of screening eligibility in patients undergoing ruptured AAA repair from 2003 to 2019 in the Vascular Quality Initiative.

OBJECTIVE: Although efforts such as the Screening Abdominal Aortic Aneurysms Very Efficiently (SAAAVE) Act have improved access to abdominal aortic aneurysm (AAA) screening, certain high-risk populations are currently excluded from the guidelines yet may benefit from screening. We therefore examined all patients who underwent repair of ruptured AAA (rAAA) to characterize those who are ineligible for screening under current guidelines and evaluate the potential impact of these restrictions on their disease. METHODS: We identified patients undergoing rAAA repair in the Vascular Quality Initiative (VQI) database between 2003 and 2019. These patients were stratified by AAA screening eligibility according to the Centers for Medicare and Medicaid reimbursement guidelines. We then described baseline characteristics to identify high-risk features of these cohorts. Groups with disproportionate representation in the screening-ineligible cohort were identified as potential targets of screening expansion. Trends over time in screening eligibility and the proportion of AAA repairs performed for rAAA were also analyzed. RESULTS: A total of 5340 patients underwent rAAA repair. The majority (66%) were screening-ineligible. When characterizing the screening-ineligible group by sex and risk factors (smoking history or family history of AAA), the largest contributors to screening ineligibility were males less than 65 years of age with a smoking history or family history of AAA (25%), males greater than 75 years of age with a smoking history (25%), and females older than 65 years of age with a smoking history (19%). In comparison with rAAAs prior to implementation of the SAAAVE act, the proportion of AAA repair performed for rupture among males undergoing AAA repair in the VQI decreased from 12% to 8% (P < .001), whereas in females, there was no change (P = .990). There was no statically significant difference in screening eligibility for either males (P = .762) or females (P = .335). CONCLUSIONS: Most patients who underwent rAAA repair were ineligible for initial AAA screening or aged out of the screening window. Furthermore, rAAA rates and screening ineligibility have not improved as much as expected since the passage of the SAAAVE Act. Our data suggest that three high-risk populations may benefit from expansion of AAA screening guidelines: males with a smoking history or family history of AAA between ages 55 and 64 years, female smokers older than 65 years, and male smokers older than 75 years who are otherwise in good health. Increased efforts to screen these high-risk populations may increase elective AAA repair and minimize the morbidity and mortality associated with rAAAs.

Not all risk scores are created equal: A comparison of risk scores for abdominal aortic aneurysm repair in administrative data and quality improvement registries.

OBJECTIVE: Accurate and contemporary prognostic risk prediction is essential to inform clinical decision-making surrounding abdominal aortic aneurysm (AAA) care. Therefore, we validated and compared three different in-hospital mortality risk scores in one administrative and two quality improvement registries. METHODS: We included patients who had undergone elective AAA repair from 2012 to 2015 in the National Inpatient Sample (NIS), Vascular Quality Initiative (VQI; excluding the New England region), and the National Surgical Quality Improvement Program (NSQIP) datasets to validate three risk scores: Medicare, the Vascular Study Group of New England (VSGNE), and Glasgow Aneurysm Score (GAS). The receiver operating characteristic area under the curve (AUC) of all risk scores was calculated, and their discrimination was compared within a dataset using the Delong test and between datasets using a Z test. We constructed graphic calibration curves for the Medicare and VSGNE risk scores and compared the calibration using an integrated calibration index, which indicates the weighted average of the absolute difference between the calibration curve and the diagonal line of perfect calibration. RESULTS: We identified a total of 25,461 NIS, 18,588 VQI, and 8051 NSQIP patients who had undergone elective open or endovascular AAA repair. Overall, the Medicare risk score was more likely to overestimate mortality in the quality improvement registries and the VSGNE risk score underestimated mortality in all the databases. After endovascular AAA repair, the Medicare risk score had a higher AUC in the NIS than in the GAS (P < .001) but not compared with the VSGNE risk score (P = .54). The VSGNE risk score was associated with a significantly higher receiver operating characteristic AUC compared with the Medicare (P < .001) and GAS (P < .001) risk scores in the VQI registry. Also, the VSGNE risk score showed improved calibration compared with the Medicare risk score across all three databases (P < .001 for all). After open repair, the Medicare risk score showed improved calibration compared with the VSGNE risk score in the NIS (P < .001). However, in the VQI registry, the VSGNE risk score compared with the Medicare risk score had significantly better discrimination (P = .008) and calibration (P < .001). CONCLUSIONS: Overall, the VSGNE risk score performed best in the quality improvement registries but underestimated mortality. However, the Medicare risk score demonstrated better calibration in the administrative dataset after open repair. Although the VSGNE risk score appeared to perform better in the quality improvement registries, its overly optimistic mortality estimates and its reliance on detailed anatomic and clinical variables reduces its broader applicability to other databases.

Comparison of treatment options for aortic necks outside standard endovascular aneurysm repair instructions for use.

OBJECTIVE/BACKGROUND: Endovascular aneurysm repair (EVAR) is associated with worse outcomes in patients whose anatomy does not meet the device instructions for use (IFU). However, whether open surgical repair (OSR) and commercially available fenestrated EVAR (Zenith Fenestrated [ZFEN]) represent better options for these patients is unknown. METHODS: We identified all patients without prior aortic surgery undergoing elective repair of abdominal aortic aneurysms with neck length ≥4 mm at a single institution with EVAR, OSR, and ZFEN. We applied device-specific aneurysm neck-related IFU to EVAR patients, and a generic EVAR IFU to ZFEN and OSR patients. Long-term outcomes were studied using propensity scores with inverse probability weighting. We compared outcomes in patients undergoing EVAR by adherence to IFU and outcomes by repair types in the subset of patients not meeting IFU. RESULTS: Of 652 patients (474 EVAR, 34 ZFEN, 143 OSR), 211 had measurements outside of standard EVAR IFU (109 EVAR [23%], 27 ZFEN [80%], and 74 OSR [52%]). Perioperative mortality was 0.5% overall. For EVAR, treatment outside the IFU was associated with significantly higher adjusted rates of long-term type IA endoleak (22% at 5 years compared to 2% within IFU, hazard ratio [HR]: 5.8 [3.1-10.9], P < .001), and lower survival (5- and 10-year survival: 56% and 34% vs 81% and 53%, HR: 2.3 [1.2-4.3], P = .01). There was no difference in reinterventions or open conversion. In patients not meeting IFU, ZFEN was associated with higher adjusted rates of reinterventions (EVAR as referent: HR: 2.6 [1.5-4.4, P < .001), whereas OSR and EVAR patients experienced similar reintervention rates (HR: 0.7 [0.4-1.1], P = .13). Patients outside the IFU experienced lower mortality with OSR compared with either EVAR (HR: 0.4 [0.2-0.9], P = .005) or ZFEN (HR: 0.3 [0.1-0.7], P = .002). When restricted to patients outside the IFU deemed fit for open repair, OSR patients remained associated with lower adjusted mortality compared with ZFEN (HR: 0.2 [0.1-0.5], P < .001), but statistical significance was lost in the comparison to EVAR (HR: 0.6 [0.3-1.1], P = .1). CONCLUSIONS: Treatment outside device-specific IFU is associated with adverse long-term outcomes. Open surgical repair is associated with higher long-term survival in patients who fall outside of the EVAR IFU and should be favored over EVAR or ZFEN in suitable patients. A three-vessel-based fenestrated strategy may not be a durable solution for difficult aortic necks, but more data are needed to evaluate the performance of newer, four-vessel devices.

Association between hospital volume and failure-to-rescue for open repairs of juxtarenal aneurysms.

BACKGROUND: A nationwide variation in mortality stratified by hospital volume exists after open repair of complex abdominal aortic aneurysms (AAAs). In the present study, we assessed whether the rates of postoperative complications or failure-to-rescue (defined as death after a major postoperative complication) would better explain the lower mortality rates among higher volume hospitals. METHODS: Using the 2004 to 2018 Vascular Quality Initiative database, we identified all patients who had undergone open repair of elective or symptomatic AAAs, in which the proximal clamp sites were at least above one renal artery. We divided the patients into hospital quintiles according to the annual hospital volume and compared the risk-adjusted outcomes. Multivariable logistic regression, adjusted for patient characteristics, operative factors, and hospital volume, was used to evaluate three outcomes: 30-day mortality, overall complications, and failure-to-rescue. RESULTS: We identified 3566 patients who had undergone open repair of elective or symptomatic complex AAAs (median age, 71 years; 29% women; 4.1% black; 48% Medicare insurance). The unadjusted rates of 30-day postoperative mortality, overall complications, and failure-to-rescue were 5.0%, 44%, and 10%, respectively. Common complications included renal dysfunction (25%), cardiac dysrhythmia (14%), and pneumonia (14%), with the specific failure-to-rescue rate ranging from 12% to 22%. On adjusted analysis, the risk-adjusted mortality rate was 2.5 times greater for the lower volume hospitals relative to the higher volume hospitals (7.4% vs 3.0%; P < .01). Although the risk-adjusted complication rates were similar between these hospital groups (30% vs 27%; P = .06), the failure-to-rescue rate was 2.3 times greater for the lower volume hospitals relative to the higher volume hospitals (6.3% vs 2.7%; P = .02). CONCLUSIONS: Higher volume hospitals had lower mortality rates after open repair of complex AAAs because they were better at the "rescue" of patients after the occurrence of postoperative complications. Both an understanding of the clinical mechanisms underlying this association and the regionalization of open repair might improve patient outcomes.

Epidemiology of endovascular and open repair for abdominal aortic aneurysms in the United States from 2004 to 2015 and implications for screening.

BACKGROUND: Contemporary national trends in the repair of ruptured abdominal aortic aneurysms (AAAs) and intact AAAs are relatively unknown. Furthermore, screening is only covered by insurance for patients aged 65 to 75 years with a family history of AAAs and for men with a positive smoking history. It is unclear what proportion of patients who present with a ruptured AAA would have been candidates for screening. METHODS: Using the National Inpatient Sample from 2004 to 2015, we identified ruptured and intact AAA admissions and repairs using the International Classification of Diseases codes. We generated the screening-eligible cohort using previously identified proportions of male smokers (87%) and all patients with a family history of AAAs (10%) and applied these proportions to patients aged 65 to 75 years. We accounted for those who could have had a previous AAA diagnosis (17%), either from screening or an incidental detection in patients aged >75 years who had presented with AAA rupture. The primary outcomes were treatment and in-hospital mortality between patients meeting the criteria for screening vs those who did not. RESULTS: We evaluated 65,125 admissions for ruptured AAAs and 461,191 repairs for intact AAAs. Overall, an estimated 45,037 admitted patients (68%) and 25,777 patients who had undergone repair for ruptured AAAs (59%) did not meet the criteria for screening. Of the patients who did not qualify, 27,653 (63%) were aged >75 years, 10,603 (24%) were aged <65 years, and 16,103 (36%) were women. Endovascular AAA repair (EVAR) increased for ruptured AAAs from 10% in 2004 to 55% in 2015 (P < .001), with operative mortality of 35%. EVAR increased for intact AAAs from 45% in 2004 to 83% in 2015 (P < .001), with operative mortality of 2.0%. CONCLUSIONS: Most patients who had undergone repair for ruptured AAAs did not qualify for screening. EVAR was the primary treatment of both ruptured and intact AAAs with relatively low in-hospital mortality. Therefore, expansion of the screening criteria to include selected women and a wider age range should be considered.