Outcomes and predictors of amputation-free survival in patients undergoing below-knee popliteal-distal bypass.

OBJECTIVE: The infrageniculate popliteal artery is a potential source for inflow in lower extremity bypass surgery in patients with isolated tibial artery disease. The objective of our study was to assess the short- and long-term outcomes of popliteal-distal bypasses using data from the Vascular Quality Initiative (VQI). METHODS: The VQI registry was queried between 2003 and 2021 for patients undergoing surgical revascularizations with the below-knee popliteal artery serving as inflow. Demographics, comorbidities, intraoperative characteristics, and postoperative complications were analyzed. Kaplan-Meier models were used to estimate amputation-free survival, survival, and freedom from amputation. Cox regression analysis was conducted to determine factors associated with major amputation or death. RESULTS: A total of 1884 procedures were analyzed. The mean age of the included patients was 67.7 years. The most frequently observed preoperative comorbidities included insulin-dependent diabetes (52.3%), coronary disease (32.4%), and end-stage renal disease (14.4%). Of all the patients, 670 (35.6%) had a history of ipsilateral endovascular intervention. The procedures were performed for a variety of indications, including tissue loss (84.3%), rest pain (10.9%), and claudication (4.8%). Intraoperatively, the outflow targets were the dorsalis pedis (31.4%), the posterior tibial (24.4%), and the anterior tibial arteries (15.6%). Vein conduit was used in 92.1% of cases. The rate of perioperative myocardial infarction (MI) was 2.4%, and the 30-day mortality was 1.9%. The median length of follow up was 371 days. Amputation-free survival was found to be 85.6% (95% confidence interval [CI], 84.0%-87.2%) at 6 months and 78.6% (95% CI, 76.6%-80.4%) at 12 months. Survival was found to be 93.4% (95% CI, 92.2%-94.5%) at 6 months and 88.6% (95% CI, 87.1%-90.0%) at 12 months. Freedom from amputation was found to be 92.0% (95% CI, 90.7%-93.3%) at 6 months and 89.0% (95% CI, 87.3%-90.4%) at 12 months. Cox regression analysis demonstrated that age greater than 65 years, congestive heart failure, coronary artery disease, and end-stage renal disease were associated with a higher risk of major amputation or death (P < .05). CONCLUSIONS: Below-knee popliteal-distal bypass is a safe and effective approach to treat severe tibial vessel occlusive disease in this challenging patient cohort. Patients exhibited low perioperative complication rates and good amputation-free survival at 1 year.

Dynamic Perioperative Platelet Activity and Cardiovascular Events in Peripheral Artery Disease.

OBJECTIVE: Patients with peripheral artery disease (PAD) undergo lower extremity revascularization (LER) for symptomatic relief or limb salvage. Despite LER, patients remain at increased risk of platelet-mediated complications, such as major adverse cardiac and limb events (MACLE). Platelet activity is associated with cardiovascular events; yet little is known about the dynamic nature of platelet activity over time. We therefore investigated the change in platelet activity over time and its association with long-term cardiovascular risk. METHODS: Patients with PAD undergoing LER were enrolled into the multicenter, prospective Platelet Activity and Cardiovascular Events (PACE) study. Platelet aggregation was assessed by light transmission aggregometry (LTA) to submaximal epinephrine (0.4µ M) immediately prior to LER, and on post-operative day 1 or 2 (POD1) and 30 (POD30). A hyperreactive platelet phenotype was defined as >60% aggregation. Patients were followed longitudinally for MACLE, defined as the composite of death, myocardial infarction, stroke, major lower extremity amputation, or acute limb ischemia leading to reintervention. RESULTS: Among 287 patients undergoing LER, mean age was 70 ± 11 years, 33% were female, 61% were white, and 89% were on baseline antiplatelet therapy. Platelet aggregation to submaximal epinephrine induced a bimodal response; 15.5%, 16.8%, and 16.4% of patients demonstrated a hyperreactive platelet phenotype at baseline, POD1, and POD30, respectively. Platelet aggregation increased by 18.5% (P=0.001) from baseline to POD1, which subsequently returned to baseline at POD30. After a median follow-up of 19 months, MACLE occurred in 165 (57%) patients. After adjustment for demographics, clinical risk factors, procedure type, and antiplatelet therapy, platelet hyperreactivity at POD1 was associated with a significant hazard of long-term MACLE (aHR 4.61, 95% CI 2.08-10.20, P<0.001). CONCLUSION: Among patients with severe PAD, platelet activity increases following LER. Platelet hyperreactivity to submaximal epinephrine on POD1 is associated with long-term MACLE. Platelet activity following LER may represent a modifiable biomarker associated with excess cardiovascular risk.

The Effect of Ipsilateral Carotid Revascularization on Contralateral Carotid Duplex Parameters in Patients with Bilateral Carotid Stenosis.

BACKGROUND: Duplex-derived velocity measurements are often used to determine the need for carotid revascularization. There is evidence that severe ipsilateral carotid stenosis can cause artificially elevated velocities in the contralateral carotid artery, which may decrease following ipsilateral revascularization. The objective of this study was to determine if contralateral carotid artery duplex velocities decrease following ipsilateral carotid endarterectomy or stenting procedures. METHODS: This is a single institutional retrospective study of prospectively collected data on all patients who underwent carotid revascularization from 2013 to 2021. Patients with immediate preoperative and first postoperative Duplex scan within 4 months of carotid revascularization at our vascular laboratory were included for analysis. Patients with contralateral occlusion were excluded. Duplex criteria used to define moderate (50-69%) and severe (>70%) stenosis were systolic velocity ≥125 cm/sec and ≥230 cm/sec, respectively. RESULTS: Between 2013 and 2021, 129 patients with bilateral carotid stenosis underwent either carotid endarterectomy (98) or a stenting procedure (31). The majority of patients (90%) underwent intervention for severe stenosis. Preoperatively, the contralateral artery was categorized as severe in 30.4% patients. After ipsilateral carotid revascularization, 86 patients (67.2%) saw a decrease in the contralateral artery peak systolic velocity (PSV), while the remaining remained stable or increased. Fifty-four patients had a change in designated stenosis severity in the contralateral artery. Between the carotid endarterectomy and stenting cohorts, there was no significant difference in the proportion of patients whose contralateral velocity decreased (69.4% vs. 61.3%, P = 0.402). Patients with coronary artery disease and diabetes were significantly less likely to experience a decrease in the contralateral artery PSV after ipsilateral intervention (P = 0.018 and P = 0.033). CONCLUSIONS: In patients with bilateral carotid disease, ipsilateral revascularization can change the contralateral artery velocity and perceived disease severity. Most patients were noted to have a decrease in the contralateral artery PSV, although almost one-third either stayed stable or increased. On multivariable analysis, patients with coronary artery disease and diabetes were less likely to see a decrease in the contralateral artery PSV after intervention. Patients who are at risk for artificial elevation of the contralateral artery may warrant a re-evaluation of the contralateral artery after ipsilateral intervention. These patients are potentially better assessed with axial imaging, although further research is needed.

Supra-Inguinal Inflow for Distal Bypasses Have Acceptable Patency and Limb Salvage Rates.

BACKGROUND: There is a paucity of data evaluating outcomes of lower extremity bypass (LEB) using supra-inguinal inflow for revascularization of infra-inguinal vessels. The purpose of this study is to report outcomes after LEB originating from aortoiliac arteries to infra-femoral targets. METHODS: The Vascular Quality Initiative database (2003-2020) was queried for patients undergoing LEB from the aortoiliac arteries to the popliteal and tibial arteries. Patients were stratified into 3 cohorts based on outflow targets (above-knee [AK] popliteal, below-knee [BK] popliteal, and tibial arteries). Perioperative and 1-year outcomes including primary patency, amputation-free survival (AFS), and major adverse limb events (MALEs) were compared. A Cox proportional hazards model was used to estimate the independent prognostic factors of outcomes. RESULTS: Of 403 LEBs, 389 (96.5%) originated from the external iliac artery, while the remaining used the aorta or common iliac artery as inflow. In terms of the distal target, the AK popliteal was used in 116 (28.8%), the BK popliteal in 151 (27.5%), and tibial vessels in 136 (43.7%) cases. BK popliteal and tibial bypasses, compared to AK popliteal bypasses, were more commonly performed in patients with chronic limb-threatening ischemia (69.5% and 69.9% vs. 48.3%; P < 0.001). Vein conduit was more often used for tibial bypass than for AK and BK popliteal bypasses (46.3% vs. 21.9% and 16.3%; P < 0.001). In the perioperative period, BK popliteal and tibial bypass patients had higher reoperation rates (16.9% and 13.2% vs. 5.2%; P = 0.02) and lower primary patency (89.4% and 89% vs. 95.7%; P = 0.04) than AK bypass patients. At 1 year, compared with AK popliteal bypasses, BK and tibial bypasses demonstrated lower primary patency (81.9% vs. 56.7% vs. 52.4%, P < 0.001) and freedom from MALE (77.6% vs. 70.2% vs. 63.1%, P = 0.04), although AFS was not significantly different (89.7% vs. 90.6% vs. 83.8%, P = 0.19).On multivariable analysis, compared with AK popliteal bypasses, tibial bypasses were independently associated with increased loss of primary patency (hazard ratio 1.9, 95% confidence interval, 1.03-3.51, P = 0.04). Subanalysis of patients with chronic limb-threatening ischemia demonstrated significantly higher primary patency in the AK popliteal cohort at discharge and 1 year, but no difference in AFS or freedom from MALE between the cohorts at follow-up. CONCLUSIONS: LEB with supra-inguinal inflow appear to have acceptable rates of 1-year patency and limb salvage in patients at high risk of bypass failure. Tibial outflow target was independently associated with worse primary patency but not with MALE or AFS.

Young patients undergoing carotid stenting procedures have an increased rate of procedural failure at 1-year follow-up.

OBJECTIVE: The outcomes of patients with premature cerebrovascular disease (age ≤55 years) who undergo carotid artery stenting are not well-defined. Our study objective was to analyze the outcomes of younger patients undergoing carotid stenting. METHODS: The Society for Vascular Surgery Vascular Quality Initiative was queried for transfemoral carotid artery stenting (TF-CAS) and transcarotid artery revascularization (TCAR) procedures between 2016 and 2020. Patients were stratified based on age ≤55 or >55 years. Primary endpoints were periprocedural stroke, death, myocardial infarction (MI), and composite outcomes. Secondary endpoints included procedural failure (defined as ipsilateral restenosis ≥80% or occlusion) and reintervention rates. RESULTS: Of the 35,802 patients who underwent either TF-CAS or TCAR, 2912 (6.1%) were ≤55 years. Younger patients were less likely than older patients to have coronary disease (30.5% vs 50.2%; P < .001), diabetes (31.5% vs 37.9%; P < .001), and hypertension (71.8% vs 89.8%; P < .001), but were more likely to be female (45% vs 35.4%; P < .001) and active smokers (50.9% vs 24.0%; P < .001) Younger patients were also more likely to have had a prior transient ischemic attack or stroke than older patients (70.7% vs 56.9%; P < .001). TF-CAS was more frequently performed in younger patients (79.7% vs 55.4%; P < .001). In the periprocedural period, younger patients were less likely to have a MI than older patients (0.3% vs 0.7%; P < .001), but there was no significant difference in the rates of periprocedural stroke (1.5% vs 2.0%; P = .173) and composite outcomes of stroke/death (2.6% vs 2.7%; P = .686) and stroke/death/MI (2.9% vs 3.2%; P = .353) between our two cohorts. The mean follow-up was 12 months regardless of age. During follow-up, younger patients were significantly more likely to experience significant (≥80%) restenosis or occlusion (4.7% vs 2.3%; P = .001) and to undergo reintervention (3.3% vs 1.7%; P < .001). However, there was no statistical difference in the frequency of late strokes between younger and older patients (3.8% vs 3.2%; P = .129). CONCLUSIONS: Patients with premature cerebrovascular disease undergoing carotid artery stenting are more likely to be African American, female, and active smokers than their older counterparts. Young patients are also more likely to present symptomatically. Although periprocedural outcomes are similar, younger patients have higher rates of procedural failure (significant restenosis or occlusion) and reintervention at 1-year follow-up. However, the clinical implication of late procedural failure is unknown, given that we found no significant difference in the rate of stroke at follow-up. Until further longitudinal studies are completed, clinicians should carefully consider the indications for carotid stenting in patients with premature cerebrovascular disease, and those who do undergo stenting may require close follow-up.

Young patients undergoing carotid endarterectomy have increased rates of recurrent disease and late neurological events.

OBJECTIVES: There are few data regarding outcomes of patients with premature cerebrovascular disease (age ≤55 years) who undergo carotid endarterectomy (CEA). The objective of this study was to analyze the demographics, presentation, perioperative and later outcomes of younger patients undergoing CEA. METHODS: The Society for Vascular Surgery Vascular Quality Initiative was queried for CEA cases between 2012 and 2022. Patients were stratified based on age of less than 55 or age greater than 55 years. Primary end points were periprocedural stroke, death, myocardial infarction, and composite outcomes. Secondary end points included restenosis (≥80%) or occlusion, late neurological events and reintervention. RESULTS: Of 120,549 patients undergoing CEA, 7009 (5.5%) were 55 years old or younger (mean age, 51.3 years). Younger patients were more likely to be African American (7.7% vs 4.5%; P < .001), female (45.2% vs 38.9%; P < .001), and active smokers (57.3% vs 24.1%; P < .001). They were less likely than older patients to have hypertension (82.5% vs 89.7%; P < .001), coronary artery disease (25.0% vs 27.3%; P < .001), and congestive heart failure (7.8% vs 11.4%; P < .001). Younger patients were significantly less likely than older patients to be on aspirin, anticoagulation, statins, or beta-blockers, but were more likely to be taking P2Y12 inhibitors (37.2 vs 33.7%; P < .001). Younger patients were more likely to present with symptomatic disease (35.1% vs 27.6%; P < .001) and were more likely to undergo nonelective CEA (19.2% vs 12.8%; P < .001). Younger and older patients had similar rates of perioperative stroke/death (2% vs 2%; P = NS) and postoperative neurological events (1.9% vs 1.8%; P = NS). However, younger patients had lower rates of overall postoperative complications compared with their older counterparts (3.7% vs 4.7%; P < .001). Of these patients, 72.6% had recorded follow-up (mean, 13 months). During follow-up, younger patients were significantly more likely than older patients to experience a late failure, defined as significant restenosis (≥80%) or complete occlusion of the operated artery (2.4% vs 1.5%; P < .001) and were more likely to experience any neurological event (3.1% vs 2.3%; P < .001). Reintervention rates did not significantly differ between the two cohorts. After controlling for covariates using a logistic regression model, age 55 years or younger was independently associated with increased odds of late restenosis or occlusion (odds ratio, 1.591; 95% confidence interval, 1.221-2.073; P < .001) as well as late neurological events (odds ratio, 1.304; 95% confidence interval, 1.079-1.576; P = .006). CONCLUSIONS: Young patients undergoing CEA are more likely to be African American, female, and active smokers. They are more likely to present symptomatically and undergo nonelective CEA. Although perioperative outcomes are similar, younger patients are more likely to experience carotid occlusion or restenosis as well as subsequent neurological events, during a relatively short follow-up period. These data suggest that younger CEA patients may require more diligent follow-up, as well as a continued aggressive approach to medical management of atherosclerosis to prevent future events related to the operated artery, given the particularly aggressive nature of premature atherosclerosis.

The impact of aorto-uni-iliac graft configuration on outcomes of endovascular repair for ruptured abdominal aortic aneurysms.

INTRODUCTION: Endovascular aneurysm repair has improved outcomes for ruptured abdominal aortic aneurysms (rAAA) compared with open repair. We examined the impact of aorto-uni-iliac (AUI) vs standard bifurcated endograft configuration on outcomes in rAAA. METHODS: Patients 18 years or older in the Vascular Quality Initiative database who underwent endovascular aneurysm repair for rAAA from January 2011 to April 2020 were included. Patient characteristics were analyzed by graft configuration: AUI or standard bifurcated. Primary and secondary outcomes included 30-day mortality, postoperative major adverse events (myocardial infarction, stroke, heart failure, mesenteric ischemia, lower extremity embolization, dialysis requirement, reoperation, pneumonia, or reintubation), and 1-year mortality. A subset propensity-score matched cohort was also analyzed. RESULTS: We included 2717 patients: 151 had AUI and 2566 had standard bifurcated repair. There was no significant difference between the groups in terms of age, major medical comorbidities, anatomic aortic neck characteristics, or rates of conversion to open repair. Patients who underwent AUI were more commonly female (30% vs 22%, P = .011) and had a history of congestive heart failure (19% vs 12%, P = .013). Perioperatively, patients who underwent AUI had a significantly higher incidence of cardiac arrest (15% vs 7%, P < .001), greater intraoperative blood loss (1.3 L vs 0.6 L, P < .001), longer operative duration (218 minutes vs 138 minutes, P < .0001), higher incidence of major adverse events (46.3% vs 33.3%, P = .001), and prolonged intensive care unit (7 vs 4.7 days, P = .0006) and overall hospital length of stay (11.4 vs 8.1 days, P = .0003). Kaplan-Meier survival analyses demonstrated significant differences in 30-day (31.1% vs 20.2%, log-rank P = .001) and 1-year mortality (41.7% vs 27.7%, log-rank P = .001). The propensity-score matched cohort demonstrated similar results. CONCLUSIONS: The AUI configuration for rAAA appears to be implemented in a sicker cohort of patients and is associated with worse perioperative and 1-year outcomes compared with a bifurcated graft configuration, which was also seen on propensity-matched analysis. Standard bifurcated graft configuration may be the preferred approach in the management of rAAA unless AUI configuration is mandated by patient anatomy or other extenuating circumstances.

Periprocedural P2Y12 inhibitors improve perioperative outcomes after carotid stenting by primarily decreasing strokes.

OBJECTIVE: The continuation of antiplatelet agents in the periprocedural period around carotid stenting (CAS) procedures is felt to be mandatory to minimize the risk of periprocedural stroke. However, the optimal antiplatelet regimen is unclear, with some advocating dual antiplatelet therapy, and others supporting the use of P2Y12 inhibitors alone. The objective of this study was to evaluate the periprocedural effect of P2Y12 inhibitors for CAS. METHODS: The Vascular Quality Initiative was used from years 2007 to 2020. All transcarotid artery revascularization (TCAR) and transfemoral carotid artery stenting (TF-CAS) procedures were included. Patients were stratified based on perioperative use of P2Y12 inhibitors as well as symptomatic status. Primary end points were perioperative neurological events (strokes and transient ischemic attacks). Secondary end points were mortality and myocardial infarction. RESULTS: A total of 31,036 CAS procedures were included for analysis, with 49.8% TCAR and 50.2% TF-CAS cases; 63.8% of patients were male and 82.3% of patients were on a P2Y12 inhibitor. P2Y12 inhibitor use was more common in males, asymptomatic patients, those older than 70 years, and concurrent statin use. P2Y12 inhibitors were more likely to be used in TCAR cases than in TF-CAS cases (87.3% vs 76.8%; P < .001). The rate of periprocedural neurological events in the whole cohort was 2.6%. Patients on P2Y12 inhibitors were significantly less likely to experience a periprocedural neurological event (2.3% vs 3.9%; P < .001) and mortality (0.6% vs 2.1%; P < .001) than those who were not on a P2Y12 inhibitor. There was no effect on the rates of myocardial infarction. On multivariate analysis, both symptomatic and asymptomatic patients on P2Y12 inhibitors were significantly less likely to develop perioperative neurological events. Additionally, the use of P2Y12 inhibitors demonstrated an independent significant effect in reducing of the rate of perioperative stroke (odds ratio, 0.29; 95% confidence interval, 0.25-0.33). Finally, additional analysis of the types of P2Y12 inhibitors used revealed that all seemed to be equally effective in decreasing the periprocedural neurological event rate. CONCLUSIONS: The use of perioperative P2Y12 inhibitors seems to markedly decrease the perioperative neurological event rate with TCAR and TF-CAS in both symptomatic and asymptomatic patients and should be strongly considered. Patients with contraindications to P2Y12 inhibitors may not be appropriate candidates for any CAS procedure. Additionally, alternative types of P2Y12 inhibitors seem to be equally effective as clopidogrel. Finally, an analysis of the Vascular Quality Initiative demonstrates that, even for TCAR cases, only 87.3% of patients seem to be on P2Y12 inhibitors in the periprocedural period, leaving room for significant improvement.

Aortobifemoral reconstruction in open abdominal aortic aneurysm repair is associated with increased morbidity and mortality.

OBJECTIVE: Much attention has been given to the influence of anatomic and technical factors, such as maximum abdominal aortic aneurysm diameter and proximal clamp position, in open abdominal aortic aneurysm repair (OSR). However, no studies have rigorously examined the correlation between site of distal anastomosis and OSR outcomes despite conventional wisdom that more proximal sites of anastomosis are preferrable when technically feasible. This study aimed to test the association between sites of distal anastomosis and clinical outcomes for patients undergoing primary elective OSR. METHODS: Our study included 5683 patients undergoing primary elective OSR at 233 centers from 2014 to 2020. Using a variety of statistical methods to account for potential confounders, including multivariable logistic regression and Cox proportional hazards modeling, as well as subgroup analysis, we examined the association between site of distal anastomosis and clinical outcomes in elective OSR. Primary outcomes were major in-hospital complication rate, 30-day mortality, and long-term survival. RESULTS: Patients undergoing elective aortobifemoral reconstruction (n = 672) exhibited significantly increased rates of smoking, chronic obstructive pulmonary disease, and peripheral artery disease in comparison to patients undergoing elective OSR with distal anastomosis to the aorta (n = 2298), common iliac artery (n = 2163), or external iliac artery (n = 550). Patients undergoing aorto-aortic tube grafting were significantly less likely to exhibit iliac aneurysmal disease and significantly more likely to be undergoing elective OSR with a suprarenal or supraceliac proximal clamp position. Using multivariable logistic regression and Cox proportional hazards analysis to control for important confounders, such as age, smoking status, and medical history, we found that distal anastomosis to the common femoral artery was associated with increased odds of major in-hospital complications (adjusted odds ratio, 1.79; 95% confidence interval, 1.46-2.18; P < .001) and reduced long-term survival (adjusted hazard ratio, 1.44; 95% confidence interval, 1.09-1.89; P = .010). We observed no significant differences in 30-day mortality across sites of distal anastomosis in our study population. CONCLUSIONS: It is generally accepted that more proximal sites of distal anastomosis should be selected in OSR when technically feasible. Our findings support this hypothesis by demonstrating that distal anastomosis to the common femoral artery is associated with increased perioperative morbidity and reduced long-term survival. Careful diligence regarding optimization of preoperative health status, perioperative care, and long-term follow-up should be applied to mitigate major complications in this patient population.

Renal transplant recipients undergoing endovascular abdominal aortic aneurysm repair have increased risk of perioperative acute kidney injury but no difference in late mortality.

OBJECTIVE: Renal transplant is associated with substantial survival advantage in patients with end-stage renal disease. However, little is known about the outcomes of renal transplant recipients (RTRs) after endovascular abdominal aortic aneurysm repair (EVAR). This study aimed to study the effect of renal transplant on perioperative outcomes and long-term survival after elective infrarenal EVAR. METHODS: The Vascular Quality Initiative database was queried for all patients undergoing elective EVAR from 2003 to 2021. Functioning RTRs were compared with non-renal transplant recipients without a diagnosis of end-stage renal disease (non-RTRs). The outcomes included 30-day mortality, acute kidney injury (AKI), new renal failure requiring renal replacement therapy (RRT), endoleak, aortic-related reintervention, major adverse cardiac events, and 5-year survival. A logistic regression analysis was used to assess the association between RTRs and perioperative outcomes. RESULTS: Of 60,522 patients undergoing elective EVAR, 180 (0.3%) were RTRs. RTRs were younger (median, 71 years vs 74.5 years; P < .001), with higher incidence of hypertension (92% vs 84%; P = .004) and diabetes (29% vs 21%; P = .005). RTRs had higher median preoperative serum creatinine (1.3 mg/dL vs 1.0 mg/dL; P < .001) and lower estimated glomerular filtration rate (51.6 mL/min vs 69.4 mL/min; P < .001). There was no difference in the abdominal aortic aneurysm diameter and incidence of concurrent iliac aneurysms. Procedurally, RTRs were more likely to undergo general anesthesia with lower amount of contrast used (median, 68.6 mL vs 94.8 ml; P < .001) and higher crystalloid infusion (median, 1700 mL vs 1500 mL; P = .039), but no difference was observed in the incidence of open conversion, endoleak, operative time, and blood loss. Postoperatively, RTRs experienced a higher rate of AKI (9.4% vs 2.7%; P < .001), but the need for new RRT was similar (1.1% vs 0.4%; P = .15). There was no difference in the rates of postoperative mortality, aortic-related reintervention, and major adverse cardiac events. After adjustment for potential confounders, RTRs remained associated with increased odds of postoperative AKI (odds ratio, 3.33; 95% confidence interval, 1.93-5.76; P < .001) but had no association with other postoperative complications. A subgroup analysis identified that diabetes (odds ratio, 4.21; 95% confidence interval, 1.17-15.14; P = .02) is associated with increased odds of postoperative AKI among RTRs. At 5 years, the overall survival rates were similar (83.4% vs 80%; log-rank P = .235). CONCLUSIONS: Among patients undergoing elective infrarenal EVAR, RTRs were independently associated with increased odds of postoperative AKI, without increased postoperative renal failure requiring RRT, mortality, endoleak, aortic-related reintervention, or major adverse cardiac events. Furthermore, 5-year survival was similar. As such, while EVAR may confer comparable benefits and technical success perioperatively, RTRs should have aggressive and maximally optimized renal protection to mitigate the risk of postoperative AKI.

Insulin Dependence is Associated with Poor Long-Term Outcomes Following AAA Repair.

BACKGROUND: While prior studies have confirmed the protective effect of diabetes on abdominal aortic aneurysm (AAA) development, much less is known about the effect of diabetes, and in particular insulin dependence, on outcomes following AAA repair. In this study, we aim to evaluate the role of insulin-dependent diabetes on short-term and long-term outcomes following open and endovascular AAA repair. METHODS: The Vascular Implant Surveillance and Interventional Outcomes Network (VISION), a registry linking the Vascular Quality Initiative (VQI) data with Medicare claims, was queried for patients who underwent open or endovascular AAA repair from 2011 to the present. Exclusion criteria were unknown diabetes status, prior aortic intervention, maximum aneurysm diameter <45 mm at presentation, and Medicare Advantage coverage due to inconsistent follow-up. Patients were stratified based on diabetes status (no diabetes versus diabetes) and insulin dependence (no diabetes or non-insulin-dependent diabetes versus insulin-dependent diabetes). RESULTS: Of the 38,437 cases in the VISION endovascular aortic aneurysm (EVAR) and open aortic aneurysm repair (OAR) databases, 21,943 met inclusion criteria. Perioperative outcomes after OAR were comparable between diabetic and nondiabetic patients. However, diabetic patients undergoing EVAR were significantly more likely to have a postoperative myocardial infarction (1.0% vs 0.6%, P = 0.04) and have a 30-day readmission (10.9% vs 8.8%, P < 0.001). Insulin-dependent diabetic patients were more likely to require a 30-day readmission after OAR (24.5% vs 13.5%, P = 0.02) and EVAR (15.1% vs 9.0%, P < 0.001); however, only insulin-dependent diabetes mellitus (IDDM) patients undergoing EVAR experienced higher rates of postoperative myocardial infarction (1.9% vs 0.7%, P < 0.01). After propensity score matching, patients with IDDM undergoing EVAR were additionally at increased risk of mortality at 1-year, 3-year, and 5-year follow-up with the highest risk occurring at the 1-year mark (hazard ratio 1.79, P < 0.0001), while IDDM patients undergoing OAR were only at a significantly increased risk of mortality at 5-year follow-up (hazard ratio 1.90, P = 0.01). CONCLUSIONS: Patients with insulin-dependent diabetes have greater than 14% one-year mortality following open or endovascular aneurysm repair, compared to 8% for all others. Our findings raise questions about whether insulin-dependent diabetics should have a higher size threshold for prophylactic repair, although further studies are needed to address this question and consider the influence of glycemic control on these outcomes.

Depressed Ejection Fraction Does Not Affect Perioperative Mortality After Thoracic Endovascular Aortic Repair for Type B Aortic Dissection.

BACKGROUND: Despite the expanded application of thoracic endovascular aortic repair (TEVAR) in patients with significant cardiac comorbidities, the effect of decreased left ventricular ejection fraction (EF) on outcomes remains unknown. The aim of this study was to compare outcomes in patients with normal and abnormal EFs undergoing TEVAR for type-B aortic dissection (TBAD). METHODS: The Vascular Quality Initiative database was reviewed from 2012 to 2020. Patients were categorized into severely reduced (EF ≤ 30%), reduced (EF 30-50%) and normal EF (EF>50%). Baseline characteristics, procedural details and 18-month outcomes were compared. Multivariable logistic regression identified factors associated with mortality, major adverse cardiac events (MACEs), and aortic-related reintervention. RESULTS: Of 1,993 patients, 38 (2%) and 208 (10%) patients had severely reduced ejection fraction (SREF) and reduced ejection fraction (REF). Patients with abnormal EF were more likely to have cardiac comorbidities and be prescribed angiotensin-converting enzyme inhibitors and anticoagulants. Perioperatively, patients with SREF were more likely to experience mortality (13.2% vs. 6.7% vs. 4.4%, P = 0.018), MACE (26.3% vs. 11.5% vs. 8%, P < 0.001), hemodialysis (13.5% vs. 5% vs. 2.9%, P = 0.001) and aortic related reintervention (21.1% vs. 13% vs. 10%, P = 0.041), compared to REF and normal ejection fraction (NEF) patients. However, these associations were not present on multivariable analysis. At 18 months, mortality was significantly higher in patients with SREF, which was confirmed on multivariable analysis, but depressed EF was not associated with increased aortic reintervention compared to NEF. CONCLUSIONS: SREF was not independently associated with perioperative mortality or MACE compared to NEF. REF had similar risk of morbidity and mortality compared to NEF in both the perioperative and early postoperative periods. TEVAR-related complications were similar among the cohorts. As such, TEVAR may be offered to appropriately selected patients regardless of EF.

Response to clopidogrel in patients undergoing lower extremity revascularization.

OBJECTIVES: Clopidogrel is effective at decreasing cardiovascular events in patients with peripheral artery disease (PAD); however, its effect on limb outcomes are less known. This study investigated the variability in response to clopidogrel and its relationship with clinical limb outcomes. METHODS: Three hundred subjects were enrolled in the Platelet Activity and Cardiovascular Events (PACE) study prior to lower extremity revascularization, of whom 104 were on clopidogrel. Light transmission platelet aggregation was measured in response to ADP 2 µm immediately prior to revascularization. Patients were followed longitudinally for a median follow-up of 18 months. The primary endpoint was major adverse limb events (MALE) defined by major amputation or reoperation of the affected limb. Patients were stratified into groups according to percent ADP-induced aggregation. Poor response to clopidogrel was defined by >50% aggregation. RESULTS: Overall, the median age was 70 (63, 76) and 35.6% were female. Twenty-nine (27.9%) patients experienced MALE during their follow-up. Median aggregation to ADP 2 µ m was 22.5% (Q1-Q3: 10%, 50%) and 27 subjects (26%) were clopidogrel poor responders. Baseline aggregation was higher in subjects who went on to develop a MALE than those without MALE (43% vs 20%, p = .017). Subjects with aggregation > median (22.5%) were more likely to experience MALE than aggregation < median (38.5% vs 17.3%, p = .029). After multivariable adjustment for age, sex, race/ethnicity, BMI, diabetes, coronary artery disease, and aspirin use, aggregation > median was associated with MALE (adjusted HR [aHR] 2.67, 95% CI 1.18-6.01, p = .018). When stratified by established cut-offs for responsiveness to clopidogrel (50% aggregation), poor responders were more likely to experience MALE than normal responders (44.4% vs 22.1%, aHR 2.18, 95% CI 1.00-4.78, p = .051). CONCLUSIONS: Among patients undergoing lower extremity revascularization on clopidogrel, higher baseline percent aggregation is associated with increased risk for major adverse limb events.

Abdominal aortic aneurysm neck dilatation and sac remodeling in fenestrated compared to standard endovascular aortic repair.

OBJECTIVE: Contemporary commercially available endovascular devices for the treatment of abdominal aortic aneurysm (AAA) include standard endovascular aortic repair (sEVAR) or fenestrated EVAR (fEVAR) endografts. However, aortic neck dilatation (AND) can occur in nearly 25% of patients following EVAR, resulting in loss of proximal seal with risk of aortic rupture. AND has not been well characterized in fEVAR, and direct comparisons studying AND between fEVAR and sEVAR have not been performed. This study aims to analyze AND in the infrarenal and suprarenal aortic segments, including seal zone, and quantify sac regression following fEVAR implantation compared to sEVAR. METHOD: A retrospective review of prospectively collected data on 20 consecutive fEVAR patients (Cook Zenith® Fenestrated) and 20 sEVAR (Cook Zenith®) patients was performed. Demographic data, anatomic characteristics, procedural details, and clinical outcome were analyzed. Pre-operative, post-operative (1 month), and longest follow-up CT scan at an average of 29.3 months for fEVAR and 29.8 months for sEVAR were analyzed using a dedicated 3D workstation (iNtuition, TeraRecon Inc, Foster City, California). Abdominal aortic aneurysm neck diameter was measured in 5 mm increments, ranging from 20 mm above to 20 mm below the lowest renal artery. Sub-analysis comparing the fEVAR to the sEVAR group at 12 months and at greater than 30 months was performed. Standard statistical analysis was done. RESULTS: Demographic characteristics did not differ significantly between the two cohorts. The fEVAR group had a larger mean aortic diameter at the lowest renal artery, shorter infrarenal aortic neck length, increased prevalence of nonparallel neck shape, and longer AAA length. On follow-up imaging, the suprarenal aortic segment dilated significantly more at all locations in the fEVAR cohort, whereas the infrarenal aortic neck segment dilated significantly less compared to the sEVAR group. Compared to the sEVAR cohort, the fEVAR patients demonstrated significantly greater positive sac remodeling as evident by more sac diameter regression, and elongation of distance measured from the celiac axis to the most cephalad margin of the sac. Device migration, endoleak occurrence, re-intervention rate, and mortalities were similar in both groups. CONCLUSION: Compared to sEVAR, patients undergoing fEVAR had greater extent of suprarenal AND, consistent with a more diseased native proximal aorta. However, the infrarenal neck, which is shorter and also more diseased in fEVAR patients, appears more stable in the post-operative period as compared to sEVAR. Moreover, the fEVAR cohort had significantly greater sac shrinkage and improved aortic remodeling. The suprarenal seal zone in fEVAR may result in a previously undescribed increased level of protection against infrarenal neck dilatation. We hypothesize that the resultant decreased endotension conferred by better seal zone may be responsible for a more dramatic sac shrinkage in fEVAR.

Comparative analysis of patients undergoing lower extremity bypass using in-situ and reversed great saphenous vein graft techniques.

OBJECTIVE: Autologous great saphenous vein (GSV) is considered the conduit of choice for lower extremity bypass (LEB). However, the optimal configuration remains the source of debate. We compared outcomes of patients undergoing LEB using in-situ and reversed techniques. METHODS: The Vascular Quality Initiative database was queried for patients undergoing LEB with a single-segment GSV in in-situ (ISGSV) and reversed (RGSV) configurations for symptomatic occlusive disease from 2003 to 2021. Patient demographics, procedural detail, and in-hospital and follow-up outcomes were collected. The primary outcome measures included primary patency at discharge or 30 days and one year. Secondary outcomes were secondary patency, and reinterventions at discharge or 30 days and one year. Cox proportional hazards models were created to determine the association between bypass techniques and outcomes of interest. RESULTS: Of 8234 patients undergoing LEBs, in-situ and reversed techniques were used in 3546 and 4688 patients, respectively. The indication for LEBs was similar between the two cohorts. ISGSV was performed more frequently from the common femoral artery and to more distal targets. RGSV bypass was associated with higher intraoperative blood loss and longer operative time. Perioperatively, ISGSV cohort had higher rates of reinterventions (13.2 vs 11.1%; p = 0.004), surgical site infection (4.2 vs 3%; p = 0.003), and lower primary patency (93.5 vs 95%; p = 0.004) but a comparable rate of secondary patency (99 vs 99.1%; p = 0.675). At 1 year, in-situ bypasses had a lower rate of reinterventions (19.4% vs 21.6%; p=0.02), with similar rates of primary (82.6 vs 81.8%; p = 0.237) and secondary patency (88.7 vs 88.9%; p = 0.625). After adjusting for significant baseline differences and potential confounders, in-situ bypass was independently associated with decreased risks of primary patency loss (HR 0.9; 95% CI, 0.82-0.98; p = 0.016) and reinterventions (HR 0.88; 95% CI, 0.8-0.97; p = 0.014) but a similar risk of secondary patency loss (HR 0.99; 95% CI, 0.86-1.16; p = 0.985) at follow-up, compared to reversed bypass. A subgroup analysis of bypasses to crural targets showed that in-situ and reversed bypasses had similar rates of primary patency loss and reinterventions at 1 year. Among patients with chronic limb-threatening ischemia, in-situ bypass was associated with a decreased risk of reinterventions but similar rates of primary and secondary patency and major amputations at 1 year. CONCLUSIONS: In patients undergoing LEBs using the GSV, in-situ configuration was associated with more perioperative reinterventions and lower primary patency rate. However, this was offset by decreased risks of loss of primary patency and reinterventions at 1 year. A thorough intraoperative graft assessment with adjunctive imaging may be performed to detect abnormalities in patients undergoing in-situ bypasses to prevent early failures. Furthermore, closer surveillance of reversed bypass grafts is warranted given the higher rates of reinterventions.

Neuroprotective association of preoperative renin-angiotensin system blocking agents use in patients undergoing carotid interventions.

OBJECTIVE: The optimal medical management strategy in the periprocedural period for patients undergoing carotid artery interventions is not well described. Renin-angiotensin-system blocking (RASB) agents are considered to be among the first line anti-hypertensive agents; however, their role in the perioperative period is unclear. The objective of this study was to examine the relationship between the use of RASB agents on periprocedural outcomes in patients undergoing carotid interventions-carotid endarterectomy (CEA), transfemoral carotid artery stenting (CAS), and transcervical carotid artery revascularization (TCAR). METHOD: The Society for Vascular Surgery Quality Initiative database was queried for all patients undergoing CAS, CEA, and TCAR between 2003 and 2020. Patients were stratified into two groups based upon their use of RASB agents in the periprocedural period. The primary endpoint was periprocedural neurologic events (including both strokes and transient ischemic attacks (TIAs)). The secondary endpoints were peri-procedural mortality and significant cardiac events, including myocardial infarction, dysrhythmia, and congestive heart failure. RESULTS: Over 150,000 patients were included in the analysis: 13,666 patients underwent TCAR, 13,811 underwent CAS, and 125,429 underwent CEA for carotid artery stenosis. Overall, 52.2% of patients were maintained on RASB agents. Among patients undergoing CEA, patients on RASB agents had a significantly lower rate of periprocedural neurologic events (1.7% versus 2.0%, p =0.001). The peri-procedural neurological event rate in the TCAR cohort was similarly reduced in those treated with RASB agents, but did not reach statistical significance (2.0% vs 2.4%, p = 0.162). Among patients undergoing CAS, there was no difference in perioperative neurologic events between the RASB treated and untreated cohorts (3.4% vs 3.2%, p = 0.234); however, the use of RASB agents was significantly associated with lower mortality (1.2% vs 1.7%, p =0.001) with CAS. The use of preoperative RAS-blocking agents did not appear to affect the overall rates of adverse cardiac events with any of the three carotid intervention types, or periprocedural mortality following CEA or TCAR. On multivariable analysis, the use of RAS-blocking agents was independently associated with lower rates of post-procedural neurologic events in patients undergoing CEA (OR 0.819, CI 0.747-0.898; p = 0.01) and TCAR (OR 0.869, CI 0.768-0.984; p = 0.026), but not in those undergoing CAS (OR 0.967, CI 0.884-1.057; p = 0.461). CONCLUSION: The use of peri-procedural RASB agents was associated with a significantly decreased rate of neurologic events in patients undergoing both CEA and TCAR. This effect was not observed in patients undergoing CAS. As carotid interventions warrant absolute minimization of perioperative complications in order to provide maximum efficacy with regard to stroke protection, the potential neuro-protective effect associated with RASB agents use following CEA and TCAR warrants further examination.

Fenestrated endovascular aortic aneurysm repair promotes positive infrarenal neck remodeling and greater sac shrinkage compared with endovascular aortic aneurysm repair.

OBJECTIVE: Endovascular aortic aneurysm repair (EVAR) has become the standard of care for abdominal aortic aneurysms (AAAs) in the modern era. Although numerous devices exist for standard infrarenal AAA repair, fenestrated EVAR (fEVAR) offers a minimally invasive alternative to traditional open repair for patients with a short infrarenal neck. Over time, aortic neck dilation can occur, leading to loss of the proximal seal, endoleaks, and AAA sac growth. In the present study, we analyzed aortic remodeling after EVAR vs fEVAR and further evaluated whether fEVAR confers a benefit in terms of sac shrinkage. METHODS: A retrospective review of prospectively collected data from 120 patients who had undergone EVAR was performed. Of these 120 patients, 30 had been treated with fEVAR (Zenith fenestrated; Cook Medical Inc, Bloomington, IN) and 90 patients were treated with EVAR devices (30 each with Endurant [Medtronic, Dublin, Ireland], Excluder [W.L. Gore & Associates, Flagstaff, AZ], and Zenith [Cook Medical Inc]). The demographic data were recorded. Also, anatomic measurements were performed for each patient preoperatively, at 30 days postoperatively, and at the longest follow-up point using three-dimensional reconstruction software. RESULTS: No significant differences were found in demographic data between the four groups. fEVAR had been used more often in aortas with large necks and irregular morphology (P = .004). At the longest follow-up, the suprarenal aorta encompassing 5, 10, and 15 mm above the lowest renal artery had dilated the most for the fEVAR group vs all EVAR groups. However, the infrarenal segment had tended to increase the least, or to even have regressed, for fEVAR compared with all three EVAR groups and was associated with the overall greatest proportion of sac shrinkage for the fEVAR group compared with the Medtronic, Gore, and Cook devices (-13.90% vs -5.75% vs -2.31% vs -4.68%, respectively; P = .025). CONCLUSIONS: Compared with EVAR, the patients treated with fEVAR had experienced greater suprarenal dilation over time, consistent with an overall greater burden of disease in the proximal native aorta. However, the infrarenal segment had dilated significantly less over time in the fEVAR group compared with all three EVAR groups, suggesting that fEVAR might stabilize the infrarenal neck, promoting positive sac remodeling, which was evidenced by the greatest degree of decrease in the largest AAA diameter in the fEVAR group.

Severity of stenosis in symptomatic patients undergoing carotid interventions might influence perioperative neurologic events.

OBJECTIVE: The carotid artery plaque burden, indirectly measured by the degree of stenosis, quantifies a patient's future embolic risk. In natural history studies, patients with moderate degrees of stenosis have had a lower stroke risk than those with severe stenosis. However, patients with symptomatic carotid stenosis who have experienced transient ischemic attack (TIA) or stroke were found to have both moderate and severe degrees of stenosis. We examined the association of carotid artery stenosis severity with the outcomes for symptomatic patients who had undergone carotid intervention, including carotid endarterectomy (CEA), transfemoral carotid artery stenting (TFCAS), and transcervical carotid artery revascularization (TCAR). METHODS: The Society for Vascular Surgery Vascular Quality Initiative database was queried for all patients who had undergone TFCAS, CEA, or TCAR between 2003 and 2020. The patients were stratified into two groups according to stenosis severity-nonsevere (0%-69%) and severe (≥70%). The primary end point was periprocedural neurologic events (stroke and TIA). The secondary end points were periprocedural death, myocardial infarction (MI), and the composite outcomes of stroke/death and stroke/death/MI in accordance with the reporting standards for carotid intervention. RESULTS: Of the 29,614 included symptomatic patients, 5296 (17.9%) had undergone TCAR, 7844 (26.5%) TFCAS, and 16,474 (55.6%) CEA for symptomatic carotid artery stenosis. In the CEA cohort, the neurologic event rate was significantly lower for the patients with severe stenosis than for those with nonsevere stenosis (2.6% vs 3.2%; P = .024). In the TCAR cohort, the periprocedural neurologic even rate was lower for those with severe stenosis than for those with nonsevere stenosis (3% vs 4.3%; P = .033). No similar difference was noted for the TFCAS cohort, with a periprocedural neurologic event rate of 3.8% in the severe group vs 3.5% in the nonsevere group (P = .518). On multivariable analysis, severe stenosis was associated with significantly decreased odds of postprocedural neurologic events after CEA (odds ratio, 0.75; 95% confidence interval, 0.6-0.92; P = .007) and TCAR (odds ratio, 0.83; 95% confidence interval, 0.69-0.99; P = .039) but not after TFCAS. CONCLUSIONS: Severe carotid stenosis, in contrast to more moderate stenosis degrees, was associated with decreased rates of periprocedural stroke and TIA in symptomatic patients undergoing TCAR and CEA but not TFCAS. The finding of increased rates of periprocedural neurologic events in symptomatic patients with lesser degrees of stenosis undergoing TCAR and CEA warrants further evaluation with a particular focus on plaque morphology and brain physiology and their inherent risks with carotid revascularization procedures.

Beta-blocker use after thoracic endovascular aortic repair in patients with type B aortic dissection is associated with improved early aortic remodeling.

OBJECTIVE: Beta-blockers (BBs) are first-line anti-impulse therapy for patients presenting with acute type B aortic dissection (TBAD). However, little is understood about their effects after aortic repair. The aim of the present study was to evaluate the role of postoperative BB use on the outcomes of thoracic endovascular aortic repair (TEVAR) in TBAD. METHODS: The Vascular Quality Initiative database was queried for all patients who had undergone TEVAR for TBAD from 2012 to 2020. Aortic-related reintervention, all-cause mortality, and the effects of TEVAR on false lumen thrombosis of the treated aortic segment were assessed and compared between patients treated with and without BBs postoperatively. Cox proportional hazards models were used to estimate the effect of BB therapy on the outcomes. RESULTS: A total of 1114 patients who had undergone TEVAR for TBAD with a mean follow-up of 18 ± 12 months were identified. The mean age was 61.1 ± 11.9 years, and 791 (71%) were men. Of the 1114 patients, 935 (84%) continued BB therapy at discharge and follow-up. The patients taking BBs were more likely to have had an entry tear originating in zones 1 to 2 (22% vs 13%; P = .022). The prevalence of acute, elective, and symptomatic aortic dissection, prevalence of concurrent aneurysms, number of endografts used, distribution of proximal and distal zones of dissection, and operative times were comparable between the two cohorts. At 18 months, significantly more complete false lumen thrombosis (58% vs 47%; log-rank P = .018) was observed for patients taking BBs, and the rates of aortic-related reinterventions (13% vs 9%; log-rank P = .396) and mortality (0.2% vs 0.7%; log-rank P = .401) were similar for patients taking and not taking BBs, respectively. Even after adjusting for clinical and anatomic factors, postoperative BB use was associated with increased complete false lumen thrombosis (hazard ratio, 1.56; 95% confidence interval, 1.10-2.21; P = .012) but did not affect mortality or aortic-related reintervention. A secondary analysis of BB use for those with acute vs chronic TBAD showed a higher rate of complete false lumen thrombosis for patients with chronic TBAD and taking BBs (59% vs 38%; log-rank P = .038). In contrast, no difference was found in the rate of complete false lumen thrombosis for those with acute TBAD between the two cohorts (58% vs 51%; log-rank P = .158). When analyzed separately, postoperative angiotensin-converting enzyme inhibitor use did not affect the rates of complete false lumen thrombosis, mortality, and aortic-related reintervention. CONCLUSIONS: BB use was associated with promotion of complete false lumen thrombosis for patients who had undergone TEVAR for TBAD. In addition to its role in the acute setting, anti-impulse control with BBs appears to confer favorable aortic remodeling and might improve patient outcomes after TEVAR, especially for those with chronic TBAD.

Prior infrarenal aortic surgery is not associated with increased risk of spinal cord ischemia after thoracic endovascular aortic repair and complex endovascular aortic repair.

OBJECTIVE: Patients with prior infrarenal aortic intervention represent an increasing demographic of patients undergoing thoracic endovascular aortic repair (TEVAR) and/or complex EVAR. Studies have suggested that prior abdominal aortic surgery is a risk factor for spinal cord ischemia (SCI). However, these results were largely based on single-center experiences with limited multi-institutional and national data that had assessed the clinical outcomes for these patients. The objective of the present study was to evaluate the effect of prior infrarenal aortic surgery on the occurrence of SCI. METHODS: The Society for Vascular Surgery Vascular Quality Initiative database was retrospectively reviewed to identify all patients aged ≥18 years who had undergone TEVAR and/or complex EVAR from January 2012 to June 2020. Patients with previous thoracic or suprarenal aortic repair were excluded. The baseline and procedural characteristics and postoperative outcomes were compared between TEVAR and/or complex EVAR with and without previous infrarenal aortic repair. The primary outcome was postoperative SCI. The secondary outcomes included postoperative hospital length of stay, bowel ischemia, renal ischemia, and 30-day mortality. Multivariate regression was used to determine the independent predictors of postoperative SCI. Additional analysis was performed of the patients who had undergone isolated TEVAR. RESULTS: A total of 9506 patients met the inclusion criteria: 8691 (91.4%) had not undergone prior infrarenal aortic repair and 815 (8.6%) had undergone previous infrarenal aortic repair. Patients with previous infrarenal repair were older with an increased prevalence of chronic kidney disease (P = .001) and cardiovascular risk factors, including hypertension, chronic obstructive pulmonary disease, and positive smoking history (P < .001). These patients also presented with a larger maximal aortic diameter (6.06 ± 1.47 cm vs 5.15 ± 1.76 cm; P < .001) and required more stent-grafts (P < .001) with increased intraoperative blood transfusion requirements (P < .001), and longer procedure times (P < .001). Univariate analysis demonstrated no differences in postoperative SCI, postoperative hospital length of stay, bowel ischemia, or renal ischemia between the two groups. The 30-day mortality was significantly higher in patients with prior infrarenal repair (P = .001). On multivariate regression, prior infrarenal aortic repair was not a predictor of postoperative SCI. In contrast, aortic dissection (odds ratio [OR], 1.65; 95% confidence interval [CI], 1.26-2.16; P < .001), number of stent-grafts deployed (OR, 1.45; 95% CI, 1.30-1.62; P < .001), and units of packed red blood cells transfused intraoperatively (OR, 1.33; 95% CI, 1.03-1.73; P = .032) were independent predictors of postoperative SCI. CONCLUSIONS: Although the patients in the TEVAR and/or complex EVAR group with prior infrarenal aortic repair constituted a sicker cohort with higher 30-day mortality, the rate of SCI was comparable to that of the patients without prior repair. Previous infrarenal repair was not associated with the risk of SCI.