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 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.

Vascular Quality Initiative assessment of compliance with Society for Vascular Surgery clinical practice guidelines on the management of extracranial cerebrovascular disease.

OBJECTIVES: Compliance with Society for Vascular Surgery (SVS) clinical practice guidelines (CPGs) is associated with improved outcomes for the treatment of abdominal aortic aneurysm, but this has not been assessed for carotid artery disease. The Vascular Quality Initiative (VQI) registry was used to examine compliance with the SVS CPGs for the management of extracranial cerebrovascular disease and its impact on outcomes. METHODS: The 2021 SVS extracranial cerebrovascular disease CPGs were reviewed for evaluation by VQI data. Compliance rates by the center and provider were calculated, and the impact of compliance on outcomes was assessed using logistic regression with inverse probability-weighted risk adjustment for each CPG recommendation, allowing for clustering by the center. Our primary outcome was a composite end point of in-hospital stroke/death. As a secondary analysis, compliance with the 2021 SVS carotid implementation document recommendations and associated outcomes were also assessed. RESULTS: Of the 11 carotid CPG recommendations, 4 (36%) could be evaluated using VQI registry data. Median center-specific CPG compliance ranged from 38% to 95%, and median provider-specific compliance ranged from 36% to 100%. After adjustment, compliance with 2 of the recommendations was associated with lower rates of in-hospital stroke/death: first, the use of best medical therapy (antiplatelet and statin therapy) in low/standard surgical risk patients undergoing carotid endarterectomy for >70% asymptomatic stenosis (event rate in compliant vs noncompliant cases 0.59% vs 1.3%; adjusted odds ratio: 0.44, 95% confidence interval: 0.29-0.66); and second, carotid endarterectomy over transfemoral carotid artery stenting in low/standard surgical risk patients with >50% symptomatic stenosis (1.9% vs 3.4%; adjusted odds ratio: 0.55, 95% confidence interval: 0.43-0.71). Of the 132 implementation document recommendations, only 10 (7.6%) could be assessed using VQI data, with median center- and provider-specific compliance rates ranging from 67% to 100%. The impact of compliance on outcomes could only be assessed for 6 (4.5%) of these recommendations, and compliance with all 6 recommendations was associated with lower stroke/death. CONCLUSIONS: Few SVS recommendations could be assessed in the VQI because of incongruity between the recommendations and the VQI data variables collected. Although guideline compliance was extremely variable among VQI centers and providers, compliance with most of these recommendations was associated with improved outcomes after carotid revascularization. This finding confirms the value of guideline compliance, which should be encouraged for centers and providers. Optimization of VQI data to promote evaluation of guideline compliance and distribution of these findings to VQI centers and providers will help facilitate quality improvement efforts in the care of vascular patients.

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.

Racial and ethnic disparities in 3-year outcomes following infrainguinal bypass for chronic limb-threatening ischemia.

OBJECTIVE: Black and Hispanic patients have had higher rates of chronic limb-threatening ischemia (CLTI) and experienced worse perioperative outcomes after lower extremity bypass compared with White patients. The underlying reasons for these disparities have remained unclear, and data on 3-year outcomes are limited. Therefore, we examined the differences in 3-year outcomes after open infrainguinal bypass for CLTI stratified by race/ethnicity and explored the potential factors contributing to these differences. METHODS: We identified all CLTI patients who had undergone primary open infrainguinal bypass in the Vascular Quality Initiative registry from 2003 to 2017 with linkage to Medicare claims through 2018 for the 3-year outcomes. Our primary outcomes were the 3-year rates of major amputation, reintervention, and mortality. We also recorded the 30-day major adverse limb events (MALE) defined as major amputation or reintervention. We used Kaplan-Meier estimation methods and multivariable Cox regression analyses to evaluate the outcomes stratified by race/ethnicity and identify contributing factors. RESULTS: Of the 7108 patients with CLTI, 5599 (79%) were non-Hispanic White, 1053 (15%) were Black, 48 (1%) were Asian, and 408 (6%) were Hispanic patients. Compared with White patients, Black patients had higher rates of 3-year major amputation (Black vs White, 32% vs 19%; hazard ratio [HR], 1.9; 95% confidence interval [CI], 1.7-2.2), reintervention (Black vs White, 61% vs 57%; HR, 1.2; 95% CI, 1.1-1.3), and 30-day MALE (Black vs White, 8.1% vs 4.9%; HR, 1.3; 95% CI, 1.2-1.4) but lower mortality (Black vs White, 38% vs 42%; HR, 0.9; 95% CI, 0.8-0.99). Hispanic patients also experienced higher rates of amputation (Hispanic vs White, 27% vs 19%; HR, 1.6; 95% CI, 1.3-2.0), reintervention (Hispanic vs White, 70% vs 57%; HR, 1.4; 95% CI, 1.2-1.6), and MALE (Hispanic vs White, 8.7% vs 4.9%; HR, 1.5; 95% CI, 1.3-1.7. However, mortality was similar between the two groups (Hispanic vs White, 38% vs 42%; HR, 0.88; 95% CI, 0.76-1.0). The low number of Asian patients prevented a meaningful assessment of amputation (Asian vs White, 20% vs 19%; HR, 0.93; 95% CI, 0.44-2.0), reintervention (Asian vs White, 55% vs 57%; HR, 0.79; 95% CI, 0.51-1.2), MALE (Asian vs White, 8.5% vs 4.9%; HR, 0.71; 95% CI, 0.46-1.1), or mortality (Asian vs White, 36% vs 42%; HR, 0.83; 95% CI, 0.52-1.3). In the adjusted analyses, the association of Black race and Hispanic ethnicity with amputation and reintervention was explained by differences in the demographic characteristics (ie, age, sex) and baseline comorbidities (ie, tobacco use, diabetes, renal disease). CONCLUSIONS: Compared with White patients, Black and Hispanic patients had higher 3-year major amputation and reintervention rates. However, mortality was lower for Black patients than for the White patients and similar between Hispanic and White patients. Disparities in amputation and reintervention were partly attributable to differences in demographic characteristics and the higher prevalence of comorbidities in Black and Hispanic patients with CLTI. Future work is necessary to determine whether interventions to improve access to care and reduce the burden of comorbidities in these populations will confer limb salvage benefits.

Disparities in 5-year outcomes and imaging surveillance following elective endovascular repair of abdominal aortic aneurysm by sex, race, and ethnicity.

OBJECTIVES: Sex, racial, and ethnic disparities in postoperative outcomes following abdominal aortic aneurysm repair have been described, but differences in long-term outcomes are poorly understood. Our aim was to identify differences in 5-year outcomes and imaging surveillance after elective endovascular aortic aneurysm repair (EVAR) by sex, race, and ethnicity and to explore potential mechanisms underlying these differences. METHODS: We identified patients undergoing elective EVAR in the Vascular Quality Initiative from 2003 to 2017 with linkage to Medicare claims through 2018 for long-term outcomes. Our primary outcome was 5-year aneurysm rupture. Secondary outcomes were 5-year reintervention and mortality and 2-year loss-to-imaging follow-up (defined as no aortic imaging from 6 to 24 months after EVAR). We used Kaplan-Meier and Cox regression analyses to evaluate these outcomes by sex/race/ethnicity and constructed multivariable models to explore potential contributing factors. RESULTS: Among 16,040 patients, 11,764 (73%) were White males, 2891 (18%) were White females, 417 (2.6%) were Black males, 175 (1.1%) were Black females, 141 (0.9%) were Asian males, 34 (0.2%) were Asian females, 277 (1.7%) were Hispanic males, and 60 (0.4%) were Hispanic females. At 5 years, rupture rates were highest in Black females at 6.4% and lowest in white males at 2.3%. Compared with White males, rupture rates were higher in White females (hazard ratio [HR], 1.5; 95% confidence interval [CI], 1.1-2.0), Black females (HR, 2.5; 95% CI, 1.0-6.0), and Asian females (HR, 5.2; 95% CI, 1.3-21). White females also had higher mortality (HR, 1.2; 95% CI, 1.2-1.3) and loss-to-imaging-follow-up (HR, 1.2; 95% CI, 1.1-1.3), whereas Black females had higher mortality (HR, 1.4; 95% CI, 1.1-1.8) and reintervention (HR, 2.0; 95% CI, 1.4-2.8). Among other groups, Black males had higher reintervention (HR, 1.4; 95% CI, 1.0-1.8), and both Black and Hispanic males had higher loss-to-imaging-follow-up (Black: HR, 1.4; 95% CI, 1.1-1.7; Hispanic: HR, 1.3; 95% CI, 1.0-1.8). In adjusted analyses, White, Black, and Asian females remained at significantly higher risk for 5-year rupture after accounting for procedure year, clinical and anatomic characteristics, surgeon and hospital volume, and loss-to-imaging follow-up. CONCLUSIONS: Compared with White male patients, Black females had higher 5-year aneurysm rupture, reintervention, and mortality after elective EVAR, whereas White females had higher rupture, mortality and loss-to-imaging-follow-up. Asian females also had higher rupture, and Black males had higher reintervention and loss-to-imaging-follow-up. These populations may benefit from improved preoperative counseling and clinical outreach after EVAR. A larger-scale investigation of current practice patterns and their impact on sex, racial, and ethnic disparities in late outcomes after EVAR is needed to identify tangible targets for improvement.

Effect of postoperative antithrombotic therapy on lower extremity outcomes after infrapopliteal bypass for chronic limb-threatening ischemia.

OBJECTIVE: Although the current guidelines have recommended single antiplatelet therapy (SAPT) for patients undergoing revascularization for chronic limb-threatening ischemia (CLTI), antithrombotic management has varied by patient and provider. Our aim was to examine the effects of different postoperative antithrombotic regimens on 3-year clinical outcomes after infrapopliteal bypass for CLTI. METHODS: We identified patients who had undergone infrapopliteal bypass for CLTI in the Vascular Quality Initiative (VQI) registry from 2003 to 2017 with linkage to Medicare claims for long-term outcomes. We divided the patients into three cohorts according to the discharge antithrombotic regimen: SAPT (aspirin or clopidogrel), dual antiplatelet therapy (DAPT; aspirin and clopidogrel), or anticoagulation (AC) plus any antiplatelet (AP) agent. To reduce selection bias, we restricted the analysis cohorts to patients treated by providers who discharged >50% of patients with each antithrombotic regimen. Our primary outcome was 3-year major adverse limb events (MALE; major amputation or reintervention). The secondary outcomes included 3-year major amputation, reintervention, and mortality. We used Kaplan-Meier and Cox regression analyses to assess these outcomes stratified by antithrombotic regimen and adjusted for demographic, comorbid, clinical, and operative differences between the treatment groups with clustering at the center level. RESULTS: Among 1812 patients (median follow-up, >2 years), 693 (38%) were discharged with SAPT, 544 (30%) with DAPT, and 575 (32%) with AC+AP. At 3 years, the MALE rates were 75% with DAPT, 74% with AC+AP, and 68% with SAPT. In adjusted analyses with SAPT as the reference group, no differences were found in 3-year MALE with DAPT (adjusted hazard ratio [aHR], 1.0; 95% confidence interval [CI], 0.85-1.3; P = .71) or AC+AP (aHR, 1.1; 95% CI, 0.96-1.3; P = .14). Across the treatment groups, we also found no differences in the individual end points of 3-year major amputation (DAPT: aHR, 0.98; 95% CI, 0.72-1.3; AC+AP: aHR, 1.3; 95% CI, 0.96-1.7), reintervention (DAPT: aHR, 1.0; 95% CI, 0.84-1.3; AC+AP: aHR, 1.1; 95% CI, 0.96-1.3), or mortality (DAPT: aHR, 1.1; 95% CI, 0.88-1.4; AC+AP: aHR, 0.95; 95% CI, 0.74-1.2). In a sensitivity analysis evaluating patients treated by providers who discharged >60%, >70%, or >80% of patients with these regimens, the association between antithrombotic regimen and MALE was unchanged. CONCLUSIONS: Compared with SAPT, DAPT and anticoagulation therapy were not associated with improved outcomes among Medicare beneficiaries who had undergone infrapopliteal bypass for CLTI at VQI participating centers. These findings support current guidelines recommending SAPT after lower extremity bypass and suggest that the routine use of DAPT or anticoagulation therapy might not provide clinical benefit in this high-risk, elderly population. However, further evaluation of the risks and benefits of various antithrombotic regimens in relevant subgroups is warranted.

Epidemiology of abdominal aortic aneurysms.

Abdominal aortic aneurysm (AAA) disease remains a major source of morbidity in developed countries and can progress to life-threatening rupture if left untreated, with exceedingly high mortality. The goal of AAA management is to identify and electively repair AAAs before rupture. AAA disease burden and outcomes have improved over time with declining tobacco use and advancements in care across patients' disease course. The introduction of endovascular AAA repair, in particular, has allowed for elective AAA repair in patients previously considered too high risk for open surgery and has contributed to lower rates of AAA rupture over time. However, these improved outcomes are not universally experienced, and disparities continue to exist in the detection, treatment, and outcomes of AAA by sex, race, and ethnicity. Mitigating these disparities requires enhanced, focused efforts at preventing disease, promoting health, and delivering appropriate care among an increasingly diverse patient population.