Systemic immunosuppression does not affect revascularization outcomes in patients with chronic limb-threatening ischemia.

OBJECTIVE: Many patients with chronic limb-threatening ischemia (CLTI) have additional comorbidities requiring systemic immunosuppression. Few studies have analyzed whether these medications may inhibit graft integration and effectiveness, or conversely, whether they may prevent inflammation and/or restenosis. Therefore, our study aim was to examine the effect of systemic immunosuppression vs no immunosuppression on outcomes after any first-time lower extremity revascularization for CLTI. METHODS: We identified all patients undergoing first-time infrainguinal bypass graft (BPG) or percutaneous transluminal angioplasty with or without stenting (PTA/S) for CLTI at our institution between 2005 and 2014. Patients were stratified by procedure type and immunosuppression status, defined as ≥6 weeks of any systemic immunosuppression therapy ongoing at the time of intervention. Immunosuppression vs nonimmunosuppression were the primary comparison groups in our analyses. Primary outcomes included perioperative complications, reintervention, primary patency, and limb salvage, with Kaplan-Meier and Cox proportional hazard models used for univariate and multivariate analyses, respectively. RESULTS: Among 1312 patients, 667 (51%) underwent BPG and 651 (49%) underwent PTA/S, of whom 65 (10%) and 95 (15%) were on systemic immunosuppression therapy, respectively. Whether assessing BPG or PTA/S patients, there were no differences noted in perioperative outcomes, including perioperative mortality, myocardial infarction, stroke, hematoma, or surgical site infection (P > .05). For BPG patients, Kaplan-Meier analysis and log-rank testing demonstrated no significant difference in three-year reintervention (37% vs 33% [control]; P = .75), major amputation (27% vs 15%; P = .64), or primary patency (72% vs 66%; P = .35) rates. Multivariate analysis via Cox regression confirmed these findings (immunosuppression hazard ratio [HR] for reintervention, 0.95; 95% CI, 0.56-1.60; P = .85; for major amputation, HR, 1.44; 95% CI, 0.70-2.96; P = .32; and for primary patency. HR, 0.97; 95% CI, 0.69-1.38; P = .88). For PTA/S patients, univariate analysis revealed similar rates of reintervention (37% vs 39% [control]; P = .57) and primary patency (59% vs 63%; P = .21); however, immunosuppressed patients had higher rates of major amputation (23% vs 12%; P = .01). After using Cox regression to adjust for baseline demographics, as well as operative and anatomic characteristics, immunosuppression was not associated with any differences in reintervention (HR, 0.75; 95% CI, 0.49-1.16; P = .20), major amputation (HR, 1.46; 95% CI, 0.81-2.62; P = .20), or primary patency (HR, 0.84; 95% CI, 0.59-1.19; P = .32). Sensitivity analyses for the differences in makeup of immunosuppression regimens (steroids vs other classes) did not alter the interpretation of any findings in either BPG or PTA/S cohorts. CONCLUSIONS: Our findings demonstrate that patients with chronic systemic immunosuppression, as compared with those who are not immunosuppressed, does not have a significant effect on late outcomes after lower extremity revascularization, as measured by primary patency, reintervention, or major amputation.

Assessment of self-reported financial conflicts of interest in vascular surgery studies.

OBJECTIVE/BACKGROUND: With increased collaboration between surgeons and industry, there has been a push towards improving transparency of conflicts of interest (COIs). This study aims to determine the accuracy of reporting of COIs among studies in major vascular surgery journals. METHODS: A literature search identified all comparative studies published from January 2018 through December 2018 from three major United States vascular surgery journals (Journal of Vascular Surgery, Vascular and Endovascular Surgery, and Annals of Vascular Surgery). Industry payments were collected using the Centers for Medicare and Medicaid Services Open Payments database. COI discrepancies were identified by comparing author declaration statements with payments found for the year of publication and year prior. RESULTS: A total of 239 studies (1642 authors) were identified. Two hundred twenty-one studies (92%) and 669 authors (63%) received undisclosed payments when utilizing a cut-off payment amount of $250. In 2018, 10,778 payments (totaling $22,174,578) were made by 145 companies. Food and beverage payments were the most commonly reported transaction (42%), but accounted for only 3% of total reported monetary values. Authors who accurately disclosed payments received significantly higher median general payments compared with authors who did not accurately disclose payments ($56,581 [interquartile range, $2441-$100,551] vs $2361 [interquartile range, $525-$9,699]; P < .001). When stratifying by dollar-amount discrepancy, the proportions of authors receiving undisclosed payments decreased with increasing payment thresholds. Multivariate analysis demonstrated that first and senior authors were both significantly more likely to have undisclosed payments (odds ratio, 2.0; 95% confidence interval, 1.1-3.6 and odds ratio, 2.9; 95% confidence interval, 1.6-5.2, respectively). CONCLUSIONS: There is a significant discordance between self-reported COI in vascular surgery studies compared with payments received in the Centers for Medicare and Medicaid Services Open Payments database. This study highlights the need for increased efforts to both improve definitions of what constitutes a relevant COI and encourage a standardized reporting process for vascular surgery studies.

Validation of the Global Limb Anatomic Staging System in first-time lower extremity revascularization.

OBJECTIVE: The Global Limb Anatomic Staging System (GLASS) was developed as a new anatomic classification scheme to grade the severity of chronic limb threatening ischemia. We evaluated the ability of this anatomic grading system to determine major adverse limb events after lower extremity revascularization. METHODS: We performed a single-institutional retrospective review of 1060 consecutive patients who had undergone 1180 first-time open or endovascular revascularization procedures for chronic limb threatening ischemia from 2005 to 2014. Using the review of angiographic images, the limbs were classified as GLASS stage 1, 2, or 3. The primary composite outcome was reintervention, major amputation (below- or above-the-knee amputation), and/or restenosis (>3.5× step-up by duplex criteria) events (RAS). The secondary outcomes included all-cause mortality, failure to cross the lesion by endovascular methods, and a comparison between bypass vs endovascular intervention. Kaplan-Meier estimates were used to determine the event rates at 1 and 5 years, and Cox regression analysis was used to adjust for baseline differences among the GLASS stages. RESULTS: Of all patients undergoing first-time revascularization, imaging studies were available for 1180 procedures (91%) for GLASS grading. Of these procedures, 552 were open bypass (47%) and 628 were endovascular intervention (53%). Compared with GLASS stage 1 disease (n = 267, 23%), stage 2 (n = 367; 31%) and stage 3 (n = 546; 42%) disease were associated with a greater risk of RAS at 1 year (stage 1, 33% vs stage 2, 48% vs stage 3, 53%) and 5 years (stage 1, 45% [reference]; stage 2, 65%; hazard ratio [HR], 1.7; 95% confidence interval [CI], 1.3-2.2; P < .001; stage 3, 69%; HR, 2.3; 95% CI, 1.7-2.9; P < .001). These differences were mainly driven by reintervention and restenosis rather than by major amputation. The 5-year mortality was similar for stage 2 and 3 compared with stage 1 disease (stage 1, 40% [reference]; stage 2, 45%; HR, 1.1; 95% CI, 0.8-1.4; P = .69; stage 3, 49%; HR, 1.2; 95% CI, 1.0-1.6; P = .11). For all attempted endovascular interventions, failure to cross a target lesion increased with advancing GLASS stage (stage 1, 4.5% vs stage 2, 6.3% vs stage 3, 13.3%; P < .01). Compared with open bypass (n = 552; 46.8%), endovascular intervention (n = 628; 53.3%) was associated with a higher rate of 5-year RAS for GLASS stage 1 (49% vs 34%; HR, 1.9; 95% CI, [1.1-3.5; P = .03), stage 2 (69% vs 52%; HR, 1.7; 95% CI, 1.2-2.5; P < .01), and stage 3 (83% vs 61%; HR, 1.5; 95% CI, 1.2-2.0; P < .01) disease. CONCLUSIONS: For patients undergoing first-time lower extremity revascularization, the GLASS can be used to predict for reintervention and restenosis. Bypass resulted in better long-term outcomes compared with endovascular intervention for all GLASS stages.

Wound location is independently associated with adverse outcomes following first-time revascularization for tissue loss.

OBJECTIVE: Few studies adequately evaluate the impact of wound location on patient outcomes after lower extremity revascularization. Consequently, we evaluated the relationship between lower extremity wound location and long-term outcomes. METHODS: We reviewed all patients at our institution undergoing any first-time open surgical bypass or percutaneous transluminal angioplasty with or without stenting for tissue loss between 2005 and 2014. We categorized wounds into three distinct groups: forefoot (ie, toes and metatarsal heads), midfoot (ie, dorsal, plantar, lateral, medial surfaces excluding toes, metatarsal heads, or heel), and heel. Limbs with multiple wounds were excluded from analyses. We compared rates of perioperative complications, wound healing, reintervention, limb salvage, amputation-free survival, and survival using χ2, Kaplan-Meier, and Cox regression analyses. RESULTS: Of 2869 infrainguinal revascularizations from 2005 to 2014, 1126 underwent a first-time revascularization for tissue loss, of which 253 patients had multiple wounds, 197 had wounds proximal to the ankle, 100 had unreliable wound information, and 576 (forefoot, n = 397; midfoot, n = 61; heel, n = 118) fit our criteria and had a single foot wound with reliable information regarding wound specifics. Patients with forefoot, midfoot, and heel wounds had similar rates of coronary artery disease, hypertension, diabetes, and smoking history (all P > .05). Conversely, there were significant differences in patient age (71 vs 69 vs 70 years), prevalence of gangrene (41% vs 5% vs 21%), and dialysis dependence (18% vs 17% vs 30%) (all P < .05). There were no statistically significant differences in perioperative mortality (1.3% vs 4.9% vs 4.2%; P = .06) or postoperative complications among the three groups. Between forefoot, midfoot, and heel wounds, there were significant differences in unadjusted 6-month rates of complete wound healing (69% vs 64% vs 53%), 3-year rates of amputation-free survival (54% vs 57% vs 35%), and survival (61% vs 72% vs 41%) (all P < .05). After adjustment, compared with forefoot wounds, heel wounds were associated with higher rates of incomplete 6-month wound healing (hazard ratio [HR], 1.6; 95% confidence interval [CI], 1.1-2.]), major amputation or mortality (HR, 1.7; 95% CI, 1.1-2.7), and all-cause mortality (HR, 1.8; 95% CI, 1.1-3.0), but not major amputation alone (HR, 2.1; 95% CI, 0.9-4.5). In open surgical bypass-first patients, heel wounds were solely associated with an increased risk of all-cause mortality (HR, 1.7; 95% CI, 1.1-2.8), whereas heel wounds in percutaneous transluminal angioplasty-first patients were associated with an increased risk of incomplete wound healing (HR, 2.2; 95% CI, 1.3-3.7), major amputation or mortality (HR, 2.3; 95% CI, 1.1-5.4), and all-cause mortality (HR, 2.8; 95% CI, 1.1-7.2). CONCLUSIONS: Heel wounds confer considerably higher short- and long-term morbidity and mortality compared with midfoot or forefoot wounds in patients undergoing any first-time lower extremity revascularization.

Search for Axionic Dark Matter Using the Magnetar PSR J1745-2900.

We report on a search for dark matter axion conversion photons from the magnetosphere of the Galactic Center magnetar PSR J1745-2900 using spectra obtained from the Karl G. Jansky Very Large Array (the National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.). No significant spectral features are detected. Using a hybrid model for PSR J1745-2900 and canonical assumptions about the dark matter density profile, we exclude axion models with axion-photon coupling g_{aγγ}>6-34×10^{-12} GeV^{-1} with 95% confidence over the mass ranges 4.2-8.4, 18.6-26.9, 33.0-41.4, 53.7-62.1, and 126.0-159.3 µeV. If there is a dark matter cusp, the limits reduce to g_{aγγ}>6-34×10^{-14} GeV^{-1}, which overlap some axion models for the observed mass ranges >33 µeV. These limits may be improved by modeling the stimulated emission that can boost the axion-photon conversion process.

Outcomes after first-time lower extremity revascularization for chronic limb-threatening ischemia in insulin-dependent diabetic patients.

OBJECTIVE: Historically, open surgical bypass provided a durable repair among diabetic patients with chronic limb-threatening ischemia (CLTI). In the current endovascular era, however, the difference in long-term outcomes between first-time revascularization strategies among patients with insulin-dependent diabetes mellitus (IDDM) is poorly understood. METHODS: We reviewed the records of all patients with IDDM undergoing a first-time infrainguinal bypass graft (BPG) or percutaneous transluminal angioplasty with or without stenting (PTA/S) for CLTI at our institution from 2005 to 2014. We defined IDDM as use of chronic insulin administration at baseline to control blood glucose levels and recorded the most recent glycated hemoglobin value available within 3 months before the procedure and fasting blood glucose level on the day of the procedure. We compared rates of wound healing, restenosis, reintervention, major amputation, and mortality between BPG and PTA/S in our population using χ2, Kaplan-Meier, and Cox regression analyses. As a sensitivity analysis, we calculated propensity scores and employed inverse probability weighting to account for nonrandom assignment to BPG vs PTA/S. RESULTS: Of 2869 infrainguinal revascularizations from 2005 to 2014, 655 limbs (316 BPG, 339 PTA/S) in 580 patients fit our criteria and underwent a first-time revascularization for CLTI. Patients undergoing BPG, compared with PTA/S, were similar in age (69 vs 68 years; P = .55), had similar rates of tissue loss (87% vs 91%; P = .07) and dialysis dependence (26% vs 28%; P = .55), were less likely to be hypertensive (84% vs 92%; P < .001), and were more likely to be current smokers (21% vs 14%; P = .02). There were no differences between BPG and PTA/S patients in mean glycated hemoglobin levels (8.1% vs 8.0%; P = .51) or mean fasting blood glucose levels (158 vs 150 mg/dL; P = .18). Although total hospital length of stay was significantly longer among BPG patients (11 vs 8 days; P < .001), perioperative complications did not differ, including acute kidney injury (19% vs 23%; P = .24), hematoma (6.0% vs 3.8%; P = .20), acute myocardial infarction (1.3% vs 2.1%; P = .43), and mortality (3.8% vs 3.0%; P = .55). BPG-first patients had significantly lower unadjusted 6-month rates of incomplete wound healing (49% vs 57%) and 5-year rates of restenosis (53% vs 72%) and reintervention (47% vs 58%; all P < .05). After adjustment, multivariable analysis suggested PTA/S-first intervention to be significantly associated with higher risk of restenosis (hazard ratio, 1.9; 95% confidence interval, 1.3-2.7) and reintervention (1.9 [1.2-2.7]). These results remained robust after inverse probability weighting. CONCLUSIONS: Among patients with IDDM and CLTI, a bypass-first strategy is associated with similar 30-day outcomes and lower restenosis and reintervention rates. These data suggest that a bypass-first approach may best serve appropriately selected, anatomically suitable patients with IDDM and pedal ischemia that requires revascularization.

Use of an Assistant Surgeon Does not Mitigate the Effect of Lead Surgeon Volume on Outcomes Following Open Repair of Intact Abdominal Aortic Aneurysms.

OBJECTIVE/BACKGROUND: While higher lead surgeon volume has been associated with lower mortality following open abdominal aortic aneurysm (AAA) repair, little is known about the impact of using an attending surgeon as assistant surgeon. The aim of this study was to determine whether the presence of an assistant surgeon, particularly a high volume assistant, mitigates the relationship between lead surgeon volume and outcomes. METHODS: All Medicare beneficiaries who underwent intact, open AAA repair between 2003 and 2008 were evaluated and nested regression models were constructed to evaluate the relationship between surgeon and assistant volume and peri-operative mortality, adjusting for comorbid conditions and hospital volume. RESULTS: In total 28,590 repairs were studied, of which 19,284 (67.5%) were performed by a single surgeon and 9306 (32.5%) included an assistant surgeon. Of cases with an assistant, 12.3% included a high volume assistant surgeon. Lower volume surgeons more frequently used an assistant (lead surgeon Q1 volume: 40%; Q2: 36%; Q3: 34%; Q4: 29%; Q5: 27% [p < .01]). In cases with no assistant, adjusted peri-operative mortality varied monotonically with surgeon volume (Q1: 4.7%; Q2: 4.4%; Q3: 4.1%; Q4: 3.3%; Q5: 3.2%). However, the use of a high or a low volume assistant surgeon, compared with no attending surgeon as assistant, was not associated with lower peri-operative mortality in any lead surgeon volume quintile, even among those operations performed by the lowest volume lead surgeons. CONCLUSION: Employing an assistant surgeon does not improve outcomes amongst any quintile of volume of the lead surgeon. As surgeons perform fewer open AAA repairs in the modern era, these data imply that even the help of a high volume assistant surgeon may not mitigate the detrimental effect of a lower volume surgeon.

Statin therapy is associated with higher long-term but not perioperative survival after abdominal aortic aneurysm repair.

BACKGROUND: Although preoperative and perioperative statin therapy improves postoperative outcomes in several populations, few data examine its association with survival after abdominal aortic aneurysm (AAA) repair. In addition, no data exist regarding the benefits of starting statins in patients with AAA not currently taking them. METHODS: We performed a registry-based study of all patients undergoing repair of AAAs in the Vascular Quality Initiative between 2003 and 2017 without documented statin intolerance. In our primary analysis, we evaluated the association between preoperative statin therapy and long-term mortality, 30-day mortality, and in-hospital myocardial infarction and stroke. As a secondary analysis, we studied the cohort of patients not taking a statin preoperatively and compared their long-term mortality on the basis of whether they were discharged on a statin. To account for nonrandom assignment to treatment, we constructed propensity scores and applied inverse probability weighting. RESULTS: We identified 40,452 AAA repairs, of which 37,950 fit our entry criteria (29,257 endovascular and 8693 open). Overall, 25,997 patients (69%) were taking a statin preoperatively, with patients undergoing endovascular aneurysm repair more frequently taking a statin than those undergoing open repair (69% compared with 66%; P < .001). After propensity weighting, preoperative statin therapy was not associated with 30-day death or in-hospital stroke or myocardial infarction. However, patients taking statins preoperatively experienced higher adjusted 1-year (94% vs 90%) and 5-year (85% vs 81%) survival from the date of surgery compared with those who were not (P < .001 overall), although subgroup analysis showed that this applied only to intact or symptomatic aneurysms. Of the 11,941 patients not taking a statin preoperatively and discharged alive, 2910 (24%) started on a statin before discharge. In our secondary analysis of the subset of patients not taking statins preoperatively, those initiated on a statin before discharge experienced higher survival at 1 year (94% vs 91%) and 5 years (89% vs 81%; P < .001 overall) than those who remained off statin therapy, with the greatest absolute long-term survival difference in patients with rupture (87% vs 62%; P < .001 overall). CONCLUSIONS: Preoperative statin therapy is associated with higher long-term survival but not perioperative mortality and morbidity in patients undergoing AAA repair, and initiating statin therapy in previously statin-naive patients is associated with markedly higher survival. All patients with AAAs without contraindications should receive statin therapy. In patients not taking a statin at the time of AAA repair, clinicians should consider initiating one before discharge.

Three-Year Results of the Endurant Stent Graft System Post Approval Study.

BACKGROUND: Long-term data following endovascular aneurysm repair (EVAR) exist but are limited to endografts that are no longer in use. The aim of the ENGAGE Post Approval Study is to describe the long-term safety and effectiveness data following EVAR using the Endurant stent graft system. METHODS: From August 2011 to June 2012, 178 patients were enrolled and treated with the Endurant stent graft system. Clinical and radiologic data were prospectively collected and analyzed. The primary end point was abdominal aortic aneurysm (AAA)-related mortality, and secondary end points were overall mortality, endoleak, secondary interventions, and device-related complications. Kaplan-Meier estimates were used for late outcomes. RESULTS: A total of 178 patients underwent EVAR with the Endurant stent graft across 24 centers (82% men; median age 71, interquartile range [IQR] 66-79). Median aortic diameter was 55 mm (IQR 51-58 mm). There was a 98.9% technical success rate. Three-year clinical and radiographic follow-up data were available for 87% and 74% of patients, respectively. Median follow-up was 37 months (IQR 30-38 months). Three-year aneurysm-related mortality rate was 1.1%, with 2 deceased patients in the perioperative period. All-cause mortality rate at 3 years was 13%. No patients suffered from aneurysm rupture or underwent conversion to open repair through 3 years of follow-up. Only 11 patients (6.2%) had undergone reintervention at 3 years. Younger age was associated with reintervention (HR 3.3 per younger decade, 95% confidence interval 1.3-7.6, P < 0.01), but neck diameter, length, and angulation were not significantly associated with reintervention. CONCLUSIONS: The Endurant stent graft system provides a safe, durable approach to treating infrarenal AAA. No patients experienced late rupture or aneurysm-related mortality, and only 1 in 16 patients underwent reintervention by 3 years. The rate of reintervention with the Endurant graft appears to be lower than other contemporary grafts, despite more liberal "Instructions For Use" parameters, but further research including direct graft comparisons will be necessary to guide appropriate graft selection.

Regional variation in racial disparities among patients with peripheral artery disease.

OBJECTIVE: Prior studies identified significant racial disparities as well as regional variation in outcomes of patients with peripheral artery disease (PAD). We aimed to determine whether regional variation contributes to these racial disparities. METHODS: We identified all white or black patients who underwent infrainguinal revascularization or amputation in 15 deidentified regions of the Vascular Quality Initiative between 2003 and 2017. We excluded three regions with <100 procedures. We used multivariable linear regression, allowing clustering at the hospital level to calculate the marginal effects of race and region on adjusted 30-day mortality, major adverse limb events (MALEs), and amputation. We compared long-term outcomes between black and white patients within each region and within patients of each race treated in different regions using multivariable Cox regression. RESULTS: We identified 90,418 patients, 15,527 (17%) of whom were black. Patients underwent 31,263 bypasses, 52,462 endovascular interventions, and 6693 amputations. Black patients were younger and less likely to smoke, to have coronary artery disease, or to have chronic obstructive pulmonary disease, but they were more likely to have diabetes, limb-threatening ischemia, dialysis dependence, and hypertension and to be self-insured or on Medicaid (all P < .05). Adjusted 30-day mortality ranged from 1.2% to 2.1% across regions for white patients and 0% to 3.0% for black patients; adjusted 30-day MALE varied from 4.0% to 8.3% for white patients and 2.4% to 8.1% for black patients; and adjusted 30-day amputation rates varied from 0.3% to 1.2% for white patients and 0% to 2.1% for black patients. Black patients experienced significantly different (both higher and lower) adjusted rates of 30-day mortality and amputation than white patients did in several regions (P < .05) but not MALEs. In addition, within each racial group, we found significant variation in the adjusted rates of all outcomes between regions (all P < .01). In adjusted analyses, compared with white patients, black patients experienced consistently lower long-term mortality (hazard ratio [HR], 0.80; 95% confidence interval [CI], 0.73-0.88; P < .001) and higher rates of MALEs (HR, 1.15; 95% CI, 1.06-1.25; P < .001) and amputation (HR, 1.33; 95% CI, 1.18-1.51; P < .001), with no statistically significant variation across the regions. However, rates of all long-term outcomes varied within both racial groups across regions. CONCLUSIONS: Significant racial disparities exist in outcomes after lower extremity procedures in patients with PAD, with regional variation contributing to perioperative but not long-term outcome disparities. Underperforming regions should use these data to generate quality improvement projects, as understanding the etiology of these disparities is critical to improving the care of all patients with PAD.

Racial disparities in outcomes after intact abdominal aortic aneurysm repair.

OBJECTIVE: We aimed to compare perioperative morbidity and mortality and late survival among black, white, and Asian patients undergoing intact abdominal aortic aneurysm (AAA) repair. METHODS: We identified all patients undergoing intact, infrarenal AAA repair in the Vascular Quality Initiative (VQI) from 2003 to 2017. We compared in-hospital outcomes by race using the Fisher exact and Kruskal-Wallis tests. Multivariable logistic and linear regression models of perioperative outcomes adjusted for differences in demographics, comorbidities, hospital volume, and procedure. We used Cox regression to evaluate late survival by race. RESULTS: In the cohort, 21,961 (94%) patients were white, 1215 (5.2%) were black, and 318 (1.4%) were Asian. Black patients were more likely to be symptomatic (black, 16%; white, 9.1%; Asian, 11%; P < .001) and to undergo endovascular aneurysm repair (EVAR; black, 87%; white, 83%; Asian, 84%; P < .001). There were no differences in 30-day mortality after EVAR (black, 1.1%; white, 1.1%; Asian, 0.8%; P = .80) or open repair (black; 4.3%; white, 2.6%; Asian, 1.9%; P = .33). However, black patients were more likely to receive new postoperative dialysis (black, 1.6%; white, 0.8%; Asian; 0.7%; P = .01) and to return to the operating room (black, 4.3%; white, 2.9%; Asian, 0.9%; P < .01). Mean hospital length of stay was longer in black patients after EVAR (black, 3.3 days; white, 2.6 days; Asian, 2.6 days; P < .001) and in Asian and black patients after open repair (black, 10.5 days; white, 8.5 days; Asian, 13.0 days; P < .001). After multivariable adjustment, black patients were more likely than white patients to have postoperative dialysis (odds ratio, 2.2; 95% confidence interval [CI], 1.3-3.6; P < .01) and return to the operating room (odds ratio, 1.6; 95% CI, 1.2-2.2; P < .01). Five-year survival was highest for Asian patients (black, 84%; white, 85%; Asian, 92%), even in the adjusted Cox model (Asian: hazard ratio, 0.6; 95% CI, 0.4-0.97; P = .04). CONCLUSIONS: Although perioperative mortality is comparable across races after AAA repair, black patients are more likely than white or Asian patients to develop new postoperative renal failure and return to the operating room, even after adjusting for differences in comorbidities, operative variables, and hospital volume. In addition, whereas Asian patients have the highest rate of postoperative myocardial infarction, they also have the highest late survival. Further studies are warranted to elucidate the mechanism of these disparities.

Long-term mortality benefit of renin-angiotensin system inhibitors in patients with chronic limb-threatening ischemia undergoing vascular intervention.

OBJECTIVE: The beneficial effect of renin-angiotensin system (RAS) inhibitors has been well-established in patients with cardiovascular disease; however, their effectiveness in patients with chronic limb-threatening ischemia (CLTI), a selected disease-burdened population, is largely unknown. The purpose of this study was to evaluate long-term outcomes of RAS inhibitor use in patients with CLTI undergoing a vascular intervention. METHODS: For this study, all patients with CLTI undergoing a first-time revascularization (bypass or endovascular) were analyzed at our institution between 2005 and 2014. Patients discharged on an RAS inhibitor (angiotensin-converting enzyme inhibitor or angiotensin receptor blocker) were compared with those not on an RAS inhibitor. The inverse probability of treatment weighting with additional regression analyses were used to determine the long-term risk of mortality and major adverse events. A sensitivity analysis was performed to assess the dose-related therapeutic response of RAS inhibitors (low-dose vs high-dose therapy). RESULTS: Between 2005 and 2014, 1303 limbs from 1161 patients were identified. Of these patients, 52% were discharged on an RAS inhibitor, with 67% discharged on a high-dose therapy and 33% on a low-dose therapy. Patients discharged on an RAS inhibitor suffered more frequently from diabetes, hypertension, and myocardial infarction, whereas those not on an RAS inhibitor had more chronic kidney disease (all P < .05). There was no difference in the proportion of patients presenting with tissue loss. After adjustment for these and other baseline covariates, RAS inhibitor use was associated with less late mortality (hazard ratio [HR], 0.78; 95% confidence interval [CI], 0.65-0.94). Discharge on a high-dose RAS inhibitor was associated with lower mortality (HR, 0.70; 95% CI, 0.57-0.86), whereas a low-dose RAS inhibitor was not associated with less mortality (HR, 0.95; 95% CI, 0.73-1.24) compared with patients not prescribed an RAS inhibitor. This association remained significant when comparing high-dose with low-dose therapy (HR, 0.74; 95% CI, 0.55-0.98). No associations were found between RAS inhibitor use and major adverse limb event (HR, 0.95; 95% CI, 0.73-1.22), major amputation (HR, 0.82; 95% CI, 0.57-1.18), or reintervention (HR, 1.05; 95% CI, 0.85-1.31). These point estimates were not different for those on angiotensin-converting enzyme inhibitors vs angiotensin receptor blockers, nor were they affected by the type of revascularization. CONCLUSIONS: Patients with CLTI prescribed an RAS inhibitor at discharge demonstrated significantly less long-term mortality, whereas limb events were unaffected. These data indicate that, in these heavily burdened patients, the benefit is restricted to those on a high dose, which underscores the importance of attaining these doses.

Early reintervention after open and endovascular abdominal aortic aneurysm repair is associated with high mortality.

OBJECTIVE: Although reinterventions are generally considered more common after endovascular aneurysm repair (EVAR) than after open surgical repair (OSR), less is known about reintervention in the early postoperative period. Furthermore, there are few data regarding the impact of early reintervention on 30-day mortality. We sought to evaluate the rates and types of reintervention after abdominal aortic aneurysm (AAA) repair and the impact of reintervention on postoperative mortality. METHODS: The American College of Surgeons National Surgical Quality Improvement Program (NSQIP) was queried from 2012 to 2014 for all intact, infrarenal AAA repairs. The 30-day reintervention was classified by Current Procedural Terminology (CPT) codes. Univariate analysis comparing patients with and without reintervention was performed with the Fisher exact test and Mann-Whitney U test. Logistic regression was used to identify predictors of reintervention and to assess the association between 30-day reintervention and mortality. RESULTS: We identified 5877 patients (OSR, 658 [11%]; EVAR, 5219 [89%]), of whom 261 underwent reintervention (OSR, 7.1%; EVAR, 4.1%; P < .01). Patients who underwent reintervention had larger aortic diameter (median, 5.7 cm vs 5.5 cm; P < .01), were more often symptomatic at presentation (16% vs 9.1%; P < .01), and were more likely to have renal insufficiency (7.7% vs 3.6%; P < .01) and history of prior abdominal operations (32% vs 26%; P = .04). Patients who underwent reintervention had higher 30-day mortality (OSR, 28% vs 2.8% [P < .001]; EVAR, 12% vs 1.0% [P < .001]) and major complications. Factors significantly associated with reintervention included open repair, diameter, symptom status, hypertension, and renal insufficiency. After adjusting for demographics, comorbidities, and type of repair, reintervention was independently associated with 30-day mortality after EVAR and OSR (odds ratio, 13; 95% confidence interval, 8-22; P < .001). CONCLUSIONS: Compared with EVAR, patients undergoing open infrarenal AAA repair were significantly more likely to undergo 30-day reintervention, which could be related to higher open anatomic complexity and lower experience of the surgeon with open repair. Reintervention after both EVAR and OSR was associated with a >10-fold increase in postoperative mortality, emphasizing the need to minimize the complications associated with reintervention.

Patient selection and perioperative outcomes of bypass and endovascular intervention as first revascularization strategy for infrainguinal arterial disease.

OBJECTIVE: The optimal initial revascularization strategy remains uncertain for patients with peripheral arterial disease. The purpose of this study was to evaluate current nationwide selection and perioperative outcomes of patients undergoing bypass or endovascular intervention for infrainguinal disease in those with no prior ipsilateral revascularization. METHODS: Patients undergoing nonemergent first-time infrainguinal revascularization were identified in the Targeted Vascular module of the National Surgical Quality Improvement Program (NSQIP) for 2011 to 2014 and stratified by symptom status (chronic limb-threatening ischemia [CLTI] or claudication). Patients treated with endovascular intervention were compared with those who underwent bypass. Multivariable logistic regression was used to evaluate current selection of patients and to establish independent associations between first-time procedures and postoperative outcomes. RESULTS: Of 5998 first-time infrainguinal revascularizations performed, 3193 were bypass procedures (63% for CLTI) and 2805 were endovascular interventions (64% for CLTI). Current patient characteristics associated with an endovascular-first approach as opposed to bypass-first in CLTI patients were age ≥80 years, tissue loss, nonsmoking, functional dependence, diabetes, dialysis, and tibial lesions, whereas age ≥80 years, nonwhite race, nonsmoking, diabetes, and tibial lesions were associated with an endovascular approach for claudication. In comparing first-time endovascular intervention with bypass, there was no difference in 30-day mortality in CLTI patients (univariate: 2.1% vs 2.2%; adjusted: odds ratio [OR], 0.7; 95% confidence interval [CI], 0.4-1.1) or claudication patients (0.3% vs 0.6%). Among CLTI patients, endovascular-first intervention was associated with lower rates of major adverse cardiovascular event (3.6% vs 4.7%; OR, 0.6; 95% CI, 0.4-0.9), surgical site infection (0.9% vs 7.7%; OR, 0.1; 95% CI, 0.1-0.2), bleeding (8.5% vs 17%; OR, 0.4; 95% CI, 0.3-0.5), unplanned reoperation (13% vs 17%; OR, 0.7; 95% CI, 0.5-0.8), and unplanned readmission (17% vs 18%; OR, 0.8; 95% CI, 0.7-0.9). Patients with claudication undergoing endovascular-first intervention also had lower rates of major adverse cardiovascular event (0.8% vs 1.6%; OR, 0.4; 95% CI, 0.2-0.95), surgical site infection (0.7% vs 6.6%; OR, 0.1; 95% CI, 0.04-0.2), bleeding (2.3% vs 6.0%; OR, 0.3; 95% CI, 0.2-0.5), unplanned reoperation (4.3% vs 6.6%; OR, 0.6; 95% CI, 0.4-0.9), and unplanned readmission (5.9% vs 9.0%; OR, 0.6; 95% CI, 0.4-0.8). Conversely, endovascular-first intervention was associated with a higher rate of secondary revascularizations within 30 days for CLTI (4.3% vs 3.1%; OR, 1.6; 95% CI, 1.04-2.3) but not for claudication (2.6% vs 1.9%; OR, 1.7; 95% CI, 0.9-3.4). CONCLUSIONS: An endovascular-first approach as a revascularization strategy for infrainguinal disease was associated with substantially lower early morbidity but not mortality, at the cost of higher rates of postoperative secondary revascularizations. As a national representation of first-time revascularizations, this study highlights the early endovascular perioperative benefit, although more robust long-term data are needed to adopt either one strategy or the other in select patients with peripheral arterial disease.

Outcomes after first-time lower extremity revascularization for chronic limb-threatening ischemia between patients with and without diabetes.

OBJECTIVE: The effect of diabetes type and insulin dependence on short- and long-term outcomes after lower extremity revascularization for chronic limb-threatening ischemia (CLTI) warrants additional study and more targeted focus. We sought to address this paucity of information by evaluating outcomes in insulin-dependent and noninsulin-dependent patients after any first-time revascularization. METHODS: We reviewed all limbs undergoing first-time infrainguinal bypass grafting (BPG) or percutaneous transluminal angioplasty with or without stenting (PTA/S) for CLTI at our institution from 2005 to 2014. Based on preoperative medication regimen, patients were categorized as having insulin-dependent diabetes (IDDM), noninsulin-dependent diabetes (NIDDM), or no diabetes (NDM). Outcomes included wound healing; major amputation; RAS events (reintervention, major amputation, or stenosis); major adverse limb events; and mortality. Outcomes were evaluated using χ2, Kaplan-Meier, and Cox regression analyses. RESULTS: Of 2869 infrainguinal revascularizations from 2005 to 2014, 1294 limbs (646 BPG, 648 PTA/S) fit our criteria. Overall, our analysis included 703 IDDM, 262 NIDDM, and 329 NDM limbs. IDDM patients, compared with NIDDM and NDM patients, were younger (69 vs 73 vs 77 years; P < .001) and more often presented with tissue loss (89% vs 77% vs 67%; P < .001), coronary artery disease (57% vs 48% vs 43%; P < .001), and end-stage renal disease (26% vs 13% vs 12%; P < .001). Perioperative complications, including mortality (3% vs 2% vs 5%; P = .07), did not differ between groups; however, complete wound healing at 6-month follow-up was significantly worse among IDDM patients (41% vs 49% vs 61%; P < .001). IDDM patients had significantly higher 3-year major amputation rates (23% vs 11% vs 8%; P < .001). Multivariable analyses illustrated that compared with NDM, IDDM was associated with significantly higher risk of both major amputation and RAS events after any first-time intervention (hazard ratio, 2.0 [95% confidence interval, 1.1-4.1] and 1.4 [1.1-1.8], respectively). Similar associations between IDDM and both major amputation and RAS events were found in patients undergoing a PTA/S-first intervention (4.1 [1.3-12.6] and 1.5 [1.1-2.2], respectively), whereas IDDM in BPG-first patients was associated with only incomplete wound healing (2.0 [1.4-4.5]). Last, compared with NDM, NIDDM was associated with lower late mortality (0.7 [0.5-0.9]). CONCLUSIONS: Compared with NDM, IDDM is associated with similar perioperative and long-term mortality but a higher risk of incomplete wound healing, major amputation, and future RAS events, especially after a PTA/S-first approach. NIDDM, on the other hand, is associated with lower long-term mortality and few adverse limb events. Overall, these data demonstrate both the importance of distinguishing between diabetes types and the potential long-term benefit of a BPG-first strategy in appropriately selected IDDM patients with CLTI.

Preoperative anemia associated with adverse outcomes after infrainguinal bypass surgery in patients with chronic limb-threatening ischemia.

OBJECTIVE: Preoperative anemia in elderly patients undergoing surgery is prevalent and associated with adverse events; however, the interaction with other risk factors in patients with chronic limb-threatening ischemia (CLTI) is not well described. The purpose of this study was to assess the association between lower hematocrit (HCT) levels on admission and postoperative outcomes after infrainguinal bypass surgery. METHODS: Patients with CLTI undergoing nonemergent infrainguinal bypass were identified in the targeted vascular module of National Surgical Quality Improvement Program (NSQIP; 2011-2014). The 30-day outcomes were compared across preoperative HCT levels: severe (≤29%), moderate (29.1%-34%), mild (34.1%-39%), or no anemia (>39%), with no anemia serving as the reference group for all analyses. Independent associations between levels of anemia and postoperative outcomes were established using multivariable logistic regression. A sensitivity analysis was performed to assess interactions between preoperative anemia and blood transfusions. RESULTS: We identified 5081 patients undergoing bypass, of which 741 (15%) had severe, 1317 (26%) moderate, 1516 (30%) mild, and 1507 (30%) no anemia. Anemic patients were older and more commonly suffered from tissue loss and comorbidities (eg, hypertension, diabetes, and renal insufficiency; all P < .001). After adjustment for baseline conditions, mortality was higher in those with severe anemia (3.1%; odds ratio [OR], 2.8; 95% confidence interval [CI], 1.3-6.3) and moderate anemia (3.0%; OR, 2.6; 95% CI, 1.2-5.5) compared with those without anemia (0.7%). Severe anemia was independently associated with major amputation (6.9% vs 3.3%; OR, 1.6; 95% CI, 1.01-2.6) compared with no anemia. Anemia on admission was additionally associated with several other adverse outcomes, such as major adverse cardiovascular event (MACE; severe: OR, 1.9; 95% CI, 1.1-3.0; moderate: OR, 1.9; 95% CI, 1.3-2.9; mild: OR, 1.6; 95% CI, 1.1-2.4) and unplanned return to the operating room (severe: OR, 1.6; 95% CI, 1.2-2.1; moderate: OR, 1.5; 95% CI, 1.2-1.8; mild, OR: 1.3; 95% CI, 1.03-1.6). Moreover, mortality associated with preoperative anemia was not different in patients receiving postoperative blood transfusions compared with those who did not, whereas MACE was significantly higher in patients with preoperative anemia and blood transfusions (interaction; P < .001). CONCLUSIONS: Mortality and major adverse events in CLTI patients undergoing infrainguinal bypass are inversely associated with preoperative HCT levels, with the highest event rates in the most severely anemic patients. The correlation between anemia and MACE-but not mortality-was stronger in those patients receiving postoperative blood transfusions. Further research is needed to define an appropriate transfusion threshold, and attention should be focused on how to best optimize anemic CLTI patients before intervention.

Adherence to lipid management guidelines is associated with lower mortality and major adverse limb events in patients undergoing revascularization for chronic limb-threatening ischemia.

OBJECTIVE: The 2013 American College of Cardiology/American Heart Association lipid management guidelines recommend high-intensity statins for all patients ≤75 years old with chronic limb-threatening ischemia (CLTI) and moderate-intensity statins for CLTI patients >75 years old without contraindications or on dialysis, but these recommendations are based primarily on coronary and stroke data. We aimed to validate these guidelines in patients with CLTI and to assess current adherence to these recommendations. METHODS: We identified all patients with CLTI who underwent first-time revascularization (endovascular or surgical) at Beth Israel Deaconess Medical Center from 2005 to 2014. Patients were classified as taking high-intensity, moderate-intensity, low-intensity, or no statin postoperatively. Outcomes included death and major adverse limb event (MALE). Propensity scores were calculated for the probability of receiving guideline-recommended intensity of statin therapy to account for nonrandom assignment of treatments. Cox regression models were constructed and adjusted for the propensity scores and further adjusted for strong potential confounders. RESULTS: After excluding patients on hemodialysis (n = 252), we identified 1019 limbs from 931 patients with a median follow-up of 380 days. Patients discharged on the recommended statin intensity had higher rates of preoperative statin use, coronary artery disease, chronic kidney disease, stroke, atrial fibrillation, congestive heart failure, and coronary artery bypass grafting; they had lower smoking rates and were less likely to be ambulatory preoperatively. Overall, only 35% were taking the recommended statin dosage: 55% of those >75 years old and 20% of those ≤75 years old. In multivariable analysis including propensity scores where appropriate, discharge on any statin was associated with lower mortality (hazard ratio [HR], 0.71; 95% confidence interval [CI], 0.60-0.90; P < .01). Discharge on the recommended intensity of statin therapy was associated with lower mortality (HR, 0.73; 95% CI, 0.60-0.99; P < .05) and lower MALE rate (HR, 0.71; 95% CI, 0.51-0.97; P < .05). Patients >75 years old and ≤75 years old accrued similar benefit. In patients >75 years old, moderate-intensity statin therapy was associated with lower rates of death and MALE compared with high-intensity therapy but did not reach statistical significance. CONCLUSIONS: Use of the recommended intensity of statin therapy in compliance with 2013 American College of Cardiology/American Heart Association lipid management guidelines is associated with significantly improved survival and lower MALE rate in patients undergoing revascularization for CLTI. Adherence to current guidelines is an appealing target for quality improvement.

Lifelong limb preservation: A patient-centered description of lower extremity arterial reconstruction outcomes.

BACKGROUND: Life expectancy is short for patients with critical limb ischemia (CLI), many of whom may fear amputation more than death. In light of the reduced life expectancy of these patients, the traditional 5-year freedom from amputation (FFA) statistic may not accurately address their concern. We developed a more relevant patient-centered calculation of major amputation risk during a patient's remaining lifetime to better answer the question, Will I ever lose my leg? METHODS: We identified all limbs undergoing first-time intervention for CLI in a large institutional database from 2005 to 2013. We calculated the traditional metrics of amputation-free survival (AFS, for which failure is death or amputation) and FFA (for which failure is amputation but deaths are censored and removed from further analysis). In addition, we propose a new term, lifelong limb preservation (LLP). LLP defines amputation as failure, but deaths are not censored and therefore reflect that LLP has been achieved. All deaths before 30 days were considered a failure in all three metrics, reflecting the risk of surgery. RESULTS: There were 1006 limbs identified as having first-time intervention for CLI (22% rest pain, 45% ulcer, 27% gangrene; 46% treated by angioplasty with or without stenting, 54% bypass). Using life-table analysis, 7-year AFS was 14% (561 events), FFA was 78% (123 events), and LLP was 86% (123 events). LLP was similar between patients undergoing angioplasty with or without stenting and bypass (7-year rates, 86% and 85%, respectively). For patients undergoing intervention for rest pain, 7-year rates were 14% for AFS, 84% for FFA, and 92% for LLP. For those undergoing treatment for ulcer, 7-year rates were 14% for AFS, 77% for FFA, and 86% for LLP. Finally, in those with gangrene, rates were 10% for AFS, 67% for FFA, and 79% for LLP. Using LLP, patients presenting with an ulcer can be told that although we cannot guarantee how long they will live, with revascularization there is approximately an 86% chance they will not lose the leg. CONCLUSIONS: These results show that the durability of our limb preservation efforts often exceeds the life expectancy of our patients. Using LLP as an outcomes assessment provides a more accurate and patient-centered answer to the question, If I have this procedure, will I ever lose my leg?

Results for primary bypass versus primary angioplasty/stent for lower extremity chronic limb-threatening ischemia.

BACKGROUND: Long-term results comparing percutaneous transluminal angioplasty with or without stenting (PTA/S) and open surgical bypass for chronic limb-threatening ischemia (CLTI) in patients who have had no prior intervention are lacking. METHODS: All patients undergoing a first-time lower extremity revascularization for CLTI by vascular surgeons at our institution from 2005 to 2014 were retrospectively reviewed. Outcomes included perioperative complications, wound healing, restenosis, primary patency, reintervention, major amputation, RAS events (ie, reintervention, major amputation, or stenosis), and mortality. Outcomes were evaluated using χ2, Kaplan-Meier, and Cox regression analyses. RESULTS: Of the 2869 total lower extremity revascularizations performed between 2005 and 2014, there were 1336 that fit our criteria of a first-time lower extremity intervention for CLTI (668 bypass procedures and 668 PTA/S procedures). Bypass patients were younger (71 vs 72 years; P = .02) and more often male (62% vs 56%; P < .02). Total mean hospital length of stay (LOS) was significantly longer after a first-time bypass (10 vs 8 days; P < .001), as were mean preoperative LOS (4 vs 3 days; P < .01) and postoperative LOS (7 vs 5 days; P < .001). There was no difference in perioperative mortality (3% vs 3%; P = .63). Surgical site infection occurred in 10% of bypass patients. Freedom from reintervention was significantly higher in patients undergoing a first-time bypass procedure (62% vs 52% at 3 years; P = .04), as was freedom from restenosis (61% vs 45% at 3 years; P < .001). Complete wound healing at 6-month follow-up was significantly better after an initial bypass (43% vs 36%; P < .01). A Cox regression model of all patients showed that reintervention was predicted by a first-time PTA/S (hazard ratio, 1.6; 95% confidence interval, 1.3-2.1) and both preoperative femoropopliteal TransAtlantic Inter-Society Consensus (TASC) C and TASC D lesions (2.0 [1.3-3.1] and 1.8 [1.3-2.7], respectively). Major amputation among all patients was predicted by an initial presentation of gangrene (2.5 [1.3-5.0]), dialysis dependence (1.9 [1.3-2.9]), diabetes (2.0 [1.1-3.8]), and preoperative femoropopliteal TASC D lesions (2.1 [1.1-4.0]) and was not predicted by procedure type. CONCLUSIONS: In this retrospective analysis, bypass for the primary treatment of CLTI showed improved 6-month wound healing, higher freedom from restenosis, improved patency rates, significantly fewer reinterventions, and higher survival than PTA/S within 3 years; however, a bypass-first approach was associated with increased total hospital LOS and wound infection. Perioperative mortality and amputation rates were similar between procedure types.

Perioperative outcome of endovascular repair for complex abdominal aortic aneurysms.

BACKGROUND: As endovascular aneurysm repair (EVAR) continues to advance, eligibility of patients with anatomically complex abdominal aortic aneurysms (AAAs) for EVAR is increasing. However, whether complex EVAR is associated with favorable outcome over conventional open repair and how outcomes compare with infrarenal EVAR remains unclear. This study examined perioperative outcomes of patients undergoing complex EVAR, focusing on differences with complex open repair and standard infrarenal EVAR. METHODS: We identified all patients undergoing nonruptured complex EVAR, complex open repair, and infrarenal EVAR in the American College of Surgeons National Surgical Quality Improvement Program Targeted Vascular Module. Aneurysms were considered complex if the proximal extent was juxtarenal or suprarenal or when the Zenith Fenestrated endograft (Cook Medical, Bloomington, Ind) was used. Independent risks were established using multivariable logistic regression analysis. RESULTS: Included were 4584 patients, with 411 (9.0%) undergoing complex EVAR, 395 (8.6%) undergoing complex open repair, and 3778 (82.4%) undergoing infrarenal EVAR. Perioperative mortality was 3.4% after complex EVAR, 6.6% after open repair (P = .038), and 1.5% after infrarenal EVAR (P = .005). Postoperative acute kidney injuries occurred in 2.3% of complex EVAR patients, in 9.5% of those undergoing complex open repair (P < .001), and in 0.9% of infrarenal EVAR patients (P = .007). Compared with complex EVAR, complex open repair was an independent predictor of 30-day mortality (odds ratio [OR], 2.2; 95% confidence interval [CI], 1.1-4.4), renal function deterioration (OR, 4.8; 95% CI, 2.2-10.5), and any complication (OR, 3.7; 95% CI, 2.5-5.5). When complex vs infrarenal EVAR were compared, infrarenal EVAR was associated with favorable 30-day mortality (OR, 0.5; 95% CI, 0.2-0.9), and renal outcome (OR, 0.4; 95% CI, 0.2-0.9). CONCLUSIONS: In this study assessing the perioperative outcomes of patients undergoing repair for anatomically complex AAAs, complex EVAR had fewer complications than complex open repair but carried a higher risk of adverse outcomes than infrarenal EVAR. Further research is warranted to determine whether the benefits of EVAR compared with open repair for complex AAA treatment are maintained during long-term follow-up.