A Contemporary Evaluation of the Centers for Medicare and Medicaid Services High-Risk Indicators for Carotid Endarterectomy.

OBJECTIVE: Compare stroke/death outcomes across Carotid Endarterectomy (CEA), Transcarotid Artery Revascularization (TCAR), and Transfemoral Carotid Artery Stenting (TFCAS) using Centers for Medicare & Medicaid Services (CMS) high-risk criterion. SUMMARY BACKGROUND DATA: Existing literature has revealed inconsistencies with CMS risk guidelines. With recent approval for TCAR and TFCAS in standard risk patients, an updated analysis of guidelines is needed. METHODS: Data from the Vascular Quality Initiative (VQI) (2016-2023) on CEA, TFCAS, or TCAR patients were used. We used inverse probability of treatment weighting to compare in-hospital stroke/death rates across procedures for high-risk criteria: contralateral occlusion (CLO), prior CEA, CAS, radiation, neck surgery, moderate to severe CHF, severe COPD (on home O2), unstable angina, recent MI (<6 mo.), and age (≥75 years-old). RESULTS: A total of 199,050 patients were analyzed, of whom 122,737 (62%) patients underwent CEA, 50,095 (25%) TCAR, and 26,218 (13%) TFCAS. TCAR had lower odds of stroke/death compared to CEA in patients with CLO (aOR=0.73 [95%CI:0.55-0.98], P=0.035) and radiation (aOR=0.44[95%CI:0.23-0.82], P=0.010). Contrary to CMS criteria, CEA patients did not have higher stroke/death in patients with prior CEA, CAS, neck surgery, moderate to severe CHF, severe COPD, unstable angina, recent MI, or age (≥75) compared to TCAR and TFCAS. CONCLUSIONS: While CMS high-risk criteria have traditionally been recognized as contraindications for CEA, our study reveals inconsistencies-with CEA performing similarly to TCAR and significantly better than TFCAS in patients with prior CEA, moderate to severe CHF, recent MI, or age (≥75). As a result, the definition of high-risk criteria may warrant reconsideration.

The effect of controlled vs uncontrolled hypertension on outcomes of carotid revascularization procedures.

BACKGROUND: Hypertension (HTN) has been implicated as a strong predictive factor for poorer outcomes in patients undergoing various vascular procedures. However, limited research is available that examines the effect of uncontrolled HTN (uHTN) on outcomes after carotid revascularization. We aimed to determine which carotid revascularization procedure yields the best outcome in this patient population. METHODS: We studied patients undergoing carotid endarterectomy (CEA), transfemoral carotid artery stenting (TFCAS), or transcarotid artery revascularization (TCAR) from April 2020 to June 2022 using data from the Vascular Quality Initiative. Patients were stratified into two groups: those with cHTN and those with uHTN. Patients with cHTN were those with HTN treated with medication and a blood pressure of <130/80 mm Hg. Patients with uHTN had a blood pressure of ≥130/80 mm Hg. Our primary outcomes were in-hospital stroke, death, myocardial infarction (MI), and 30-day mortality. Our secondary outcomes were postoperative hypotension or HTN, reperfusion syndrome, prolonged length of stay (LOS) (>1 day), stroke/death, and stroke/death/MI. We used logistic regression models for the multivariate analysis. RESULTS: A total of 34,653 CEA (uHTN, 11,347 [32.7%]), 8199 TFCAS (uHTN, 2307 [28.1%]), and 17,309 TCAR (uHTN, 4990 [28.8%]) patients were included in this study. There was no significant difference in age between patients with cHTN and patients with uHTN for each carotid revascularization procedure. However, compared with patients with cHTN, patients with uHTN had significantly more comorbidities. uHTN was associated with an increased risk of combined in-hospital stroke/death/MI after CEA (adjusted odds ratio [aOR], 1.56; 95% confidence interval [CI], 1.30-1.87; P < .001), TFCAS (aOR, 1.59; 95% CI, 1.21-2.08; P < .001), and TCAR (aOR, 1.39; 95% CI, 1.12-1.73; P = .003) compared with cHTN. Additionally, uHTN was associated with a prolonged LOS after all carotid revascularization methods. For the subanalysis of patients with uHTN, TFCAS was associated with an increased risk of stroke (aOR, 1.82; 95% CI, 1.39-2.37; P < .001), in-hospital death (aOR, 3.73; 95% CI, 2.25-6.19; P < .001), reperfusion syndrome (aOR, 6.24; 95% CI, 3.57-10.93; P < .001), and extended LOS (aOR, 1.87; 95% CI, 1.51-2.32; P < .001) compared with CEA. There was no statistically significant difference between the outcomes of TCAR compared with CEA. CONCLUSIONS: The results from this study show that patients with uHTN are at a higher risk of stroke and death postoperatively compared with patients with cHTN, highlighting the importance of treating HTN before undergoing elective carotid revascularization. Additionally, in patients with uHTN, TFCAS yields the worst outcomes, whereas CEA and TCAR proved to be safer interventions. Patients with uTHN with symptomatic carotid disease treated with CEA or TCAR have better outcomes compared with those treated with TFCAS.

The obesity paradox exists for perioperative complications and mortality following lower extremity arterial bypass surgery.

OBJECTIVE: The obesity paradox refers to a phenomenon by which obese individuals experience lower risk of mortality and even protective associations from chronic disease sequelae when compared with the non-obese and underweight population. Prior literature has demonstrated an obesity paradox after cardiac and other surgical procedures. However, the relationship between body mass index (BMI) and perioperative complications for patients undergoing major open lower extremity arterial revascularization is unclear. METHODS: We queried the Vascular Quality Initiative for individuals receiving unilateral infrainguinal bypass between 2003 and 2020. We used multivariable logistic regression to assess the relationship of BMI categories (underweight [<18.5 kg/m2], non-obese [18.5-24.9 kg/m2], overweight [25-29.9 kg/m2], Class 1 obesity [30-34.9 kg/m2], Class 2 obesity [35-39.9 kg/m2], and Class 3 obesity [>40 kg/m2]) with 30-day mortality, surgical site infection, and adverse cardiovascular events. We adjusted the models for key patient demographics, comorbidities, and technical and perioperative characteristics. RESULTS: From 2003 to 2020, 60,588 arterial bypass procedures met inclusion criteria for analysis. Upon multivariable logistic regression with the non-obese category as the reference group, odds of 30-day mortality were significantly decreased among the overweight (odds ratio [OR], 0.64; 95% confidence interval [CI], 0.53-0.78), Class 1 obese (OR, 0.65; 95% CI, 0.52-0.81), Class 2 obese (OR, 0.66; 95% CI, 0.48-0.90), and Class 3 obese (OR, 0.61; 95% CI, 0.39-0.97) patient categories. Conversely, odds of 30-day mortality were increased in the underweight patient group (OR, 1.58; 95% CI, 1.16-2.13). Furthermore, a BMI-dependent positive association was present, with odds of surgical site infections with patients in Class 3 obesity having the highest odds (OR, 2.10; 95% CI, 1.60-2.76). Finally, among the adverse cardiovascular event outcomes assessed, only myocardial infarction (MI) demonstrated decreased odds among overweight (OR, 0.82; 95% CI, 0.71-0.96), Class 1 obese (OR, 0.78; 95% CI, 0.65-0.93), and Class 2 obese (OR, 0.66; 95% CI, 0.51-0.86) patient populations. Odds of MI among the underweight and Class 3 obesity groups were not significant. CONCLUSIONS: The obesity paradox is evident in patients undergoing lower extremity bypass procedures, particularly with odds of 30-day mortality and MI. Our findings suggest that having higher BMI (overweight and Class 1-3 obesity) is not associated with increased mortality and should not be interpreted as a contraindication for lower extremity arterial bypass surgery. However, these patients should be under vigilant surveillance for surgical site infections. Finally, patients that are underweight have a significantly increased odds of 30-day mortality and may be more suitable candidates for endovascular therapy.

Postoperative Outcomes and One-Year Mortality of Patients on Chronic Anticoagulation Medications Undergoing Infrainguinal Bypass.

BACKGROUND: Patients requiring open infrainguinal bypass (IIB) frequently are taking chronic anticoagulation (AC) medications. Taking these medications in the preoperative setting may affect the outcomes of surgery. This study aims to evaluate postoperative outcomes and 1-year mortality of patients taking chronic AC medications that undergo IIB. METHODS: Using data obtained from the Vascular Quality Initiative from January 2011 to October 2021, patients on warfarin or any direct oral anticoagulants (DOAC) within 30 days of IIB were compared with patients not taking chronic AC medications. The primary outcomes were in-hospital, 30-day, and 1-year mortality. The secondary outcomes included total procedure time, need for perioperative packed red blood cell transfusion, prolonged length of hospital stay, postoperative myocardial infarction or stroke, and graft patency at discharge. A subgroup analysis was performed comparing patients taking warfarin with those taking DOACs. Univariate analyses and multivariate logistic regression, Kaplan Meier survival, and Cox regression analyses were used to analyze the data for postoperative and 1-year outcomes, respectively. RESULTS: A total of 55,076 patients underwent IIB during the study period, and 11,547 (20.97%) were on chronic AC prior to surgery. The 2 cohorts differed significantly in almost every demographic and clinical characteristic. Multivariate analyses adjusting for 45 potential confounders revealed that there was no significant difference in in-hospital, 30-day, and 1-year mortality. The total procedure time for the chronic AC cohort was on average 11.46 ± 2.16 min longer (P ≤ 0.001) and there was a greater risk of prolonged length of stay in the hospital (adjusted odds ratio [aOR]: 1.19, 95% confidence interval [CI]: 1.13-1.26, P < 0.001). These patients also returned to the operating room (OR) at a greater rate (aOR: 1.12, 95% CI: 1.05-1.19; P = 0.016) and demonstrated a significantly lower rate of graft patency at discharge (aOR: 0.73, 95% CI: 0.62-0.86, P = 0.001). On subgroup analysis, multivariate analysis demonstrated lower 30-day mortality for the DOAC group in comparison to the warfarin group (aOR: 0.74, 95% CI: 0.57-0.94, P = 0.015), but no significant differences in in-hospital and 1-year mortality. CONCLUSIONS: Patients taking AC medications within 30 days prior to IIBs may require more perioperative red blood cell transfusions, longer hospitalizations, and return to the OR at a greater rate. They are also at an increased risk for loss of graft patency at discharge. However, these patients are not at increased risk of in-hospital, 30-day, or 1-year mortality. IIB can, therefore, be performed safely in patients taking chronic AC medications.

Modality-specific outcomes of patients undergoing carotid revascularization in the setting of recent myocardial infarction.

OBJECTIVE: Recent myocardial infarction (MI) represents a real challenge in patients requiring any vascular procedure. There is currently a lack of data on the effect of preoperative MI on the outcomes of carotid revascularization methodology (carotid enterectomy [CEA], transfemoral carotid artery stenting [TFCAS], or transcarotid artery revascularization [TCAR]). This study looks to identify modality-specific outcomes for patients with recent MI undergoing carotid revascularization. METHODS: Data was collected from the Vascular Quality Initiative (2016-2022) for patients with carotid stenosis in the United States and Canada with recent MI (<6 months) undergoing CEA, TFCAS, or TCAR. In-hospital outcomes after TFCAS vs CEA and TCAR vs CEA were compared. TCAR vs TFCAS were compared in a secondary analysis. We used logistic regression models to compare the outcomes of these three procedures in patients with recent MI, adjusting for potential confounders. Primary outcomes included 30-day in-hospital rates of stroke, death, and MI. Secondary outcomes included stroke/death, stroke/death/MI, postoperative hypertension, postoperative hypotension, prolonged length of stay (>2 days), and 30-day mortality. RESULTS: The final cohort included 1217 CEA (54.2%), 445 TFCAS (19.8%), and 584 TCAR (26.0%) cases. Patients undergoing CEA were more likely to have prior coronary artery bypass graft/percutaneous coronary intervention and to use anticoagulant. Patients undergoing TFCAS were more likely to be symptomatic, have prior congestive heart failure, chronic obstructive pulmonary disease, chronic kidney disease, and undergo urgent operations. Patients undergoing TCAR were more likely to have higher rates of American Society of Anesthesiologists class IV to V, P2Y12 inhibitor, and protamine use. In the univariate analysis, CEA was associated with a lower rate of ipsilateral stroke (P = .079), death (P = .002), and 30-day mortality (P = .007). After adjusting for confounders, TFCAS was associated with increased risk of stroke/death (adjusted odds ratio [aOR], 2.69; 95% confidence interval [CI], 1.36-5.35; P = .005) and stroke/death/MI (aOR, 1.67; 95% CI, 1.07-2.60; P = .025) compared with CEA. However, TCAR had similar outcomes compared with CEA. Both TFCAS and TCAR were associated with increased risk of postoperative hypotension (aOR, 1.62; 95% CI, 1.18-2.23; P = .003 and aOR, 1.74; 95% CI, 1.31-2.32; P ≤ .001, respectively) and decreased risk of postoperative hypertension (aOR, 0.59; 95% CI, 0.36-0.95; P = .029 and aOR, 0.50; 95% CI, 0.36-0.71; P ≤ .001, respectively) compared with CEA. CONCLUSIONS: Although recent MI has been established as a high-risk criterion for CEA and an approved indication for TFCAS, this study showed that CEA is safer in this population with lower risk of stroke/death and stroke/death/MI compared with TFCAS. TCAR had similar stroke/death/MI outcomes in comparison to CEA in patients with recent MI. Further prospective studies are needed to confirm our findings.

Patients with Prior Exposure to a Combination of Statins & Angiotensin-Converting Enzyme Inhibitors (ACE-Is)/Angiotensin Receptor Blockers (ARBs) Have Better Outcomes after Carotid Revascularization than Patients with Prior Exposure to Statins Alone: A MultiCenter Analysis.

BACKGROUND: Statin use has been studied and confirmed to have a beneficial impact on perioperative carotid endarterectomy (CEA) and carotid artery stenting (CAS) outcomes. The benefits of Angiotensin-converting enzyme inhibitors (ACE-I) in hypertension, ischemic heart disease, heart failure, diabetes mellitus, and renal disease are well-known; however, the impact of continuing or withholding ACE-Is/angiotensin receptor blockers (ARBs) on CEA and CAS outcomes is not addressed well in the literature. This study aimed to evaluate the impact of preoperative statin use combined with ACE-Is/ARBs in patients undergoing CEA or CAS on mortality and morbidity using a multi-institutional database. METHODS: Using the data of all patients who underwent carotid artery revascularization, including CEA, transcarotid artery revascularization, and transfemoral carotid artery stenting from 2016 to 2021 in the Vascular Quality Initiative data, we determined as our primary outcome 30-day mortality/stroke after carotid revascularization based on periop exposure to statins alone, or the combination of statins and ACE-Is/ARBs. Secondary outcomes were postop myocardial infarction and postop congestive heart failure. Poisson regression with robust variance was used to determine postop outcomes comparing the combination of statin and ACE-Is/ARBs group with statins alone group. RESULTS: A total of 131,285 patients were included in the study, with 59,860 (46%) patients receiving statin only, and 71,425 (54%) receiving both statin and ACE-Is/ARBs preoperatively. Both patient groups differed significantly in preop clinical and demographic characteristics. After adjusting for potential confounders, the statins plus ACE-I/ARB group had a 12% lower risk of postop mortality/stroke (Incident Rate Ratio comparing Statin/ACE group to Statins Only group [IRR] 0.88, 95% confidence interval 0.81-0.95, P = 0.001), 18% lower risk of postop congestive heart failure (IRR 0.82, 95% CI 0.68-0.98, P = 0.029), and similar risk of postop myocardial infarction (IRR 1.05 95% confidence interval 0.91-1.20, P = 0.54) compared to the statin-only group. CONCLUSION: Statins combined with ACE-Is/ARBs perioperatively offer better protection compared to statins alone in patients undergoing carotid revascularization surgery. We recommend the continuation of ACE-Is/ARBs use in patients undergoing carotid revascularization, especially if they have concurrent hypertension. Further prospective studies are needed to evaluate the benefit of adding ACE-Is/ARBs.

Perioperative Blood Transfusion Is Associated with Worse 30-Day Mortality and Complications After Thoracic Endovascular Aortic Repair.

BACKGROUND: It is not uncommon for patients requiring vascular surgery, and in particular aortic surgery, to have increased requirements for blood transfusion. However, studies examining the effects of perioperative transfusion for thoracic endovascular aortic repair (TEVAR) are limited. Using large multicenter data, we aimed to study the impact of perioperative blood transfusion on 30-day mortality and complications after TEVAR. METHODS: A total of 9,263 patients who underwent TEVAR were included in this retrospective study from the multicenter Vascular Quality Initiative cohort spanning 2010-2022. We excluded patients who were post-traumatic, anemic (World Health Organization criteria: hemoglobin < 12 g/dl and < 13 g/dl for females and males respectively), who underwent open conversions or presented with ruptured aneurysms. Primary outcomes were 30-day mortality and stroke. Secondary outcomes were postop congestive heart failure (CHF), respiratory complications, spinal cord ischemia (SCI), myocardial infarction (MI) and any postop complications (composite variable). Poisson regression with robust variance was performed to determine the risk of post op outcomes comparing patients who received red blood cells (RBCs) to those who did not. RESULTS: Comparing patients without any transfusion (n = 8,223), perioperative transfusion of 1-3 units (n = 735) was associated with 3-fold increased risk of 30-day mortality (adjusted relative risk [aRR] 3.30, 95% confidence interval [CI] 2.39,4.57, P < 0.001), almost 2-fold increased risk of stroke (aRR 1.98, 95% CI 1.24,3.15, P = 0.004), 2.7-fold increased risk of SCI (aRR 2.66, 95% CI 1.87-3.77, P < 0.001), 3-fold increased risk of MI (aRR 3.40, 95% CI 2.30, 5.03, P < 0.001), 2-fold increased risk of CHF (aRR 2.04, 95% CI 1.09, 3.83, P = 0.03), 3.5-fold increased risk of respiratory complications (aRR 3.49, 95% CI 2.67, 4.56, P < 0.001), and 2-fold increased risk of any postop complication (aRR 2.36, 95% CI 2.04, 2.73, P < 0.001). These effects were even higher in patients transfused 4 or more units (n = 305) than seen in the effects seen in those transfused 1-3 units; comparing each group to patients who received none. CONCLUSIONS: In hemodynamically stable patients undergoing TEVAR for nonemergent/emergent and nontraumatic indications, transfusion of any amount perioperatively is associated with worse 30-day mortality, stroke, SCI, MI, CHF, and respiratory complications. A conservative transfusion approach and multidisciplinary care to identify complications and rescue TEVAR patients who receive any amount of RBCs perioperatively might help improve outcomes. Future studies to understand the mechanisms of outcomes for transfused patients are needed.

Two-Stage Offers No Advantages over Single-Stage Arteriovenous Creation: An Analysis of Multicenter National Data.

BACKGROUND: Traditionally, arteriovenous fistulas (AVF) involving the basilic vein (BV) have been created in 1 or 2 stages to allow time for the vein to enlarge before superficialization for potential better fistula maturation. Previous single institution studies and meta-analyses have found conflicting outcomes between single-stage and 2-stage procedures. Our study aims to use a large national database to assess the difference in outcomes between single-stage and 2-stage procedures for dialysis access. METHODS: We studied all patients undergoing BV AVF creation in the Vascular Quality Initiative (VQI) from 2011 to 2021. Patients were split into single-stage or a planned 2-stage procedure for dialysis access. Primary outcomes included dialysis use with index fistula, maturity rate, and number of days from surgery to fistula use. Secondary outcomes included patency (defined by physical exam or imaging on follow-up), 30-day mortality, and postoperative complications (bleeding, steal syndrome, thrombosis, or neuropathy). Logistic regression models were used to assess the association between staged dialysis access procedures and primary outcomes of interest. RESULTS: The cohort consisted of 22,910 individuals of which 7,077 (30.9%) had a 2-staged dialysis access procedure and 15,833 (69.1%) had a single-staged procedure. Average follow-up was 345 days in the single stage and 420 days for 2-stage. Baseline characteristics were significantly different between the 2 groups in terms of medical comorbidities. Primary outcomes were significant for more patients in the 2-stage group undergoing dialysis with the index fistula compared to single stage (31.5% vs. 22.2%, P < 0.0001), significant decrease in days to use in current dialysis patients (103.9 days single stage versus 141.0 days 2-stage, P < 0.0001), and no difference in maturity at follow-up (19.3% single-stage and 17.4% 2-stage, P = 0.354). Secondary outcomes revealed no difference in 30-day mortality or patency (89.8% single-stage and 89.1% 2-stage, P = 0.383), but a significant difference in postoperative complications with a 2-stage procedure compared to 1-stage (1.6% vs. 1.1%, P = 0.026). Finally, a spline model was used to determine that a preoperative vein of 3 mm or less could be a cutoff in which a 2-stage procedure might be beneficial. CONCLUSIONS: This study demonstrates that when dialysis access fistulas are created using the BV, there is no difference in maturity rate or 1-year patency when assessing single-stage versus 2-stage procedures. However, 2-stage procedures significantly delay the time of first use of the fistula and increase postoperative complications. Therefore, we suggest performing single stage procedures when the vein is of appropriate diameter to minimize multiple procedures, complications and expedite time to maturity.

Cost-Effectiveness Analysis of Open Versus Endovascular Revascularization for Chronic Mesenteric Ischemia.

BACKGROUND: Recent studies have shown a trend supporting endovascular revascularization (ER) in the treatment of chronic mesenteric ischemia (CMI). However, few studies have compared the cost effectiveness of ER and open revascularization (OR) for this indication. The purpose of this study is to conduct a cost-effectiveness analysis comparing open versus ER for CMI. METHODS: We built a Markov model with Monte Carlo microsimulation using transition probabilities and utilities from existing literature for CMI patients undergoing OR versus ER. Costs were derived from the hospital perspective using the 2020 Medicare Physician Fee Schedule. The model randomized 20,000 patients to either OR or ER and allowed for 1 subsequent reintervention with 3 other intervening health states: alive, alive with complications, and dead. Quality-adjusted life years (QALYs), costs, and incremental cost-effectiveness ratio (ICER) were analyzed over a 5-year period. One-way sensitivity and probabilistic sensitivity analyses were conducted to study the impact of parameter variability on cost effectiveness. RESULTS: OR cost $4,532 for 1.03 QALYs while ER cost $5,092 for 1.21 QALYs, leading to an ICER of $3,037 per QALY gained in the ER arm. This ICER was less than our willingness to pay threshold of $100,000. Sensitivity analysis demonstrated that our model was most sensitive to costs, mortality, and patency rates after OR and ER. Probabilistic sensitivity analysis demonstrated ER would be considered cost effective 99% of iterations. CONCLUSIONS: This study found that while 5-year costs for ER were greater than OR, ER afforded greater QALYs than OR. Although ER is associated with lower long-term patency and higher rates of reintervention, it appears to be more cost effective than OR for the treatment of CMI.

Anemia is associated with higher mortality and morbidity after thoracic endovascular aortic repair.

BACKGROUND: It is uncertain whether preoperative anemia is independently associated with thoracic endovascular aortic repair (TEVAR) outcomes. Using a national vascular surgery database, we evaluated the associations between preoperative anemia and 30-day mortality, postoperative complications, and 1-year survival for patients undergoing TEVAR. METHODS: We retrospectively analyzed all patients in the Vascular Quality Initiative who had undergone TEVAR for aortic dissection, aortic aneurysm, penetrating aortic ulcer, hematoma, or thrombus between January 2011 and December 2019. We excluded patients with a ruptured aneurysm, traumatic dissection, emergent repair, treated aorta distal to zone 5, polycythemia, transfusion of >4 U of packed red blood cells intraoperatively or postoperatively, and missing data on hemoglobin level or surgical indications. The final study cohort was dichotomized into two groups: normal/mild anemia (women, ≥10 g/dL; men, ≥12 g/dL) and moderate/severe anemia (women, <10 g/dL; male, <12 g/dL). Propensity scores by stratification were used to control for confounding in the analysis of the association between the outcomes of 30-day mortality, postoperative complications, and 1-year survival and a binary indicator variable of moderate/severe anemia vs normal/mild anemia. Kaplan-Meier analysis and log-rank tests were used to compare the 1-year survival between the two groups. A Cox regression model was fitted to assess the associations between anemia and survival outcomes. RESULTS: A total of 3391 patients were analyzed, 958 (28.3%) of whom had had moderate/severe anemia. After adjustment for multiple clinical factors using propensity score stratification, moderate/severe anemia was associated with a 141% increased odds of 30-day mortality (adjusted odds ratio [aOR], 2.41; 95% confidence interval [CI], 1.15-5.05; P = .019), 58% increased odds of any in-hospital complication (aOR, 1.58; 95% CI, 1.17-2.13; P = .003), 281% increased odds of intraoperative transfusion (aOR, 3.81; 95% CI, 2.68-5.53; P < .001). In addition, moderate/severe anemia was associated with significantly worse survival within the first year after TEVAR (log-rank P < .001; 1-year survival rate using Kaplan-Meier estimates, 86.4% ± 1.3% standard error vs 92.5% ± 0.6% standard error) and with an increased risk of mortality in the first postoperative year (adjusted hazard ratio, 1.81; 95% CI, 1.16-2.82; P = .009). CONCLUSIONS: We found that moderate or severe anemia is associated with significantly increased odds of mortality, postoperative complications, and worse 1-year survival after TEVAR. Future studies are needed to evaluate the effect of anemia correction on the outcomes of TEVAR.

Immediate and delayed complications of inferior vena cava filters.

OBJECTIVE: Inferior vena cava (IVC) filter placement has increased dramatically in the past two decades. However, literature supporting the efficacy of these devices has been limited and controversial. In the present study, we have evaluated the predictors and rates of technical complications after IVC filter insertion in a large national database. METHODS: The Vascular Quality Initiative registry was explored (January 2013 to December 2020). Immediate complications were defined as venous injury requiring treatment, filter misplacement (failure to open, deployed >20 mm from intended site or in wrong vein, embolized to the heart), angulation >20°, and insertion site complications. Delayed complications were defined as migration, angulation >15°, fracture, caval and/or iliac thrombosis, filter thrombus, fragment embolization, and perforation. The Pearson χ2 test was used to compare the baseline characteristics between the patients who had developed immediate and/or delayed complications and those who had not. The predictors of these complications were evaluated using multivariable logistic regression, Cox proportional hazard regression, and Kaplan-Meier survival analysis. RESULTS: A total of 14,784 patients were included in the present analysis, with a median follow-up of 11 months (interquartile range, 4-16 months). The rate of immediate and delayed complications was 1.8% and 3.1%, respectively. Angulation (1.2%) was the most common immediate complication, and filter thrombosis (1.6%) was the most common delayed complication. Compared with the patients with no immediate complications, those with immediate complications were more likely to have had abnormal anatomy (6.0% vs 1.7%; P < .001) and a landing zone other than infrarenal (7.0% vs 4.2%; P = .02). Compared with their counterparts, those with delayed complications were less likely to have received statins (21.0% vs 29.5%; P = .006) and were more likely to have a family history of venous thromboembolism (8.0% vs 5.1%; P = .047). Logistic regression analysis revealed that renal vein visualization was associated a 50% reduction (adjusted odds ratio [aOR], 0.50; 95% confidence interval [CI], 0.27-0.92; P = .027) in the odds of immediate complications and female sex and abnormal anatomy were associated with a 41% (aOR, 1.41; 95% CI, 1.08-1.85; P = .013) and 244% (aOR, 3.44; 95% CI, 1.66-7.16; P < .001) increase in the odds of immediate complications, respectively. Immediate (P = .21) and delayed (P = .51) complications did not result in increased mortality. CONCLUSIONS: The immediate and delayed IVC filter complication rates were 1.8% and 3.1%, respectively, but the occurrence of complications was not associated with increased mortality. Female sex was associated with an increase in the development of immediate complications. The incidence of immediate complications might be mitigated if advanced imaging were used for renal vein visualization before IVC filter deployment. Delayed complications might be avoided if IVC filter retrieval were performed in a timely fashion and institutional retrieval protocols were optimized.