Prognostic Value of a Classification System for Iliofemoral Stenting in Patients with Chronic Venous Obstruction.

OBJECTIVE: This retrospective, multicentre study aimed to assess the prognostic value of a proposed classification system for chronic venous obstruction (CVO) patients undergoing successful interventional procedures. METHODS: This study analysed data from 13 vascular centres, including 1 033 patients with CVO treated between 2015 - 2019. The patients were classified into five category types: 1 - non-thrombotic iliac vein lesion; 2 - CVO of iliac segment; 3 - CVO of iliofemoral segment above common femoral vein confluence; 4 - CVO of iliofemoral segment extending into the femoral vein (FV) or deep femoral vein (DFV); and 5 - CVO of iliofemoral segment involving both DFV and FV. Stent deployment, complications, and follow ups were evaluated. Univariate and multivariate analyses were performed to identify predictors of primary patency loss. RESULTS: Mean age of the patients was 44.0 ± 14.7 years, with 59.9% being women. A median of two stents were used for unilateral cases and five stents for bilateral cases. At 12 months of follow up, primary patency rates for types 1 - 5 were 94.9%, 90.3%, 80.8%, 60.6%, and 39.4%, respectively. These rates were strongly correlated with the extension of CVO and showed significant differences between each type. Univariate analysis identified predictors of primary patency loss as the type of CVO, history of deep vein thrombosis, and the total number of stents. In the multivariate analysis, the significant independent predictors of primary patency loss were the type of CVO and the total number of stents. CONCLUSION: The proposed anatomical classification of iliofemoral CVO will help to predict intervention outcomes and facilitate comparison of stent outcomes in future studies. However, further evaluation and validation in prospective studies are needed to confirm the utility of this classification.

Incidence and Outcomes of Visceral Ischemia in Acute Aortic Occlusion.

BACKGROUND: Acute aortic occlusion (AAO) is a morbid diagnosis in which mortality correlates with severity of ischemia on presentation. Visceral ischemia (VI) is challenging to diagnose and its presentation as a consequence of AAO is not well-studied. We aim to identify characteristics associated with VI in AAO to facilitate diagnosis. METHODS: Patients diagnosed with AAO who underwent revascularization were identified retrospectively from institutional records (2006-2020). The primary outcome was the development of VI (intra-abdominal ischemia). Univariate analysis was used to compare demographic, exam, imaging, and intraoperative variables between patients with and without VI in the setting of AAO. RESULTS: Ninety-one patients were included. The prevalence of VI was 20.9%. Preoperative comorbidities, time to revascularization, and operative approach did not differ between patients with and without VI. Patients with VI more frequently were transferred from outside institutions (100% vs. 53%, P = 0.02), presented with advanced acute limb ischemia (Rutherford III 36.9% vs. 7.5%, P < 0.01), and had elevated preoperative serum lactate (4.31 vs. 2.41 mmol/L, P < 0.01). VI patients had an increased occurrence of bilateral internal iliac artery (IIA) occlusion (47.4% vs. 18.1%, P = 0.01). Unilateral IIA occlusion, level of aortic occlusion, and patency of inferior mesenteric arteries were not associated with VI. Patients with VI had worse postoperative outcomes. In particular, VI conferred significant risk of mortality (odds ratio 5.45, P < 0.01). CONCLUSIONS: Visceral ischemia is a common consequence of AAO. Elevated lactate, bilateral IIA occlusion, and advanced acute limb ischemia (ALI) should increase clinical suspicion for concomitant VI with AAO and may facilitate earlier diagnosis to improve outcomes.

Racial Disparities in Treatment Indications and Outcomes for Limb Ischemia.

BACKGROUND: Studies suggest that the Affordable Care Act (ACA) of 2014 has improved access to vascular care and vascular outcomes among patients suffering from peripheral arterial disease (PAD). We sought to examine the racial disparities that exist in patients with PAD who have undergone lower extremity bypass (LEB) or a peripheral vascular intervention (PVI) using the Vascular Quality initiative (VQI) database. METHODS: The VQI infrainguinal and PVI datasets were queried for patients receiving elective and urgent LEB or PVI between 2016, 2 years after ACA implementation, and in 2021. Patients undergoing interventions urgently/emergently or for aneurysm were excluded. The primary outcome was major adverse limb event (MALE-defined as any vascular reintervention or above-ankle amputation) free survival at 1 year. Standard statistical methods were utilized as appropriate. RESULTS: A total of 17,455 LEB and 87,475 PVIs were included in this analysis. Black persons present at a younger age when compared to non-Hispanic White persons (NHW) and are more likely to have diabetes, hypertension, end-stage renal disease (ESRD), and higher rates of prior amputation. Black persons are more likely to present with chronic limb-threatening ischemia (CLTI) rather than claudication, and in a more urgent setting. Postoperative outcomes show higher rates of major amputations among racial minorities, specifically Black persons for both LEB (1.8% vs. 0.8% P < 0.001) and PVI (20.8% vs. 16.8% P < 0.001). Black persons are at higher risk of 1-year MALE for LEB (36.7% vs. 29.9% P < 0.001) and PVI (31.0% vs. 21.7%; P < 0.001). Even after adjusting for confounding variables, Black persons have a higher risk of 1-year MALE for LEB, with an adjusted hazard ratio (aHR) of 1.15 (95% CI [1.05-1.26], P = 0.003) and PVI (aHR 1.18 95% CI [1.12-1.24], P < 0.001). Other major determinates of 1-year MALE on multivariate Cox regression included CLTI (LEB aHR 1.57 95% CI [1.43-1.72], P < 0.001; PVI aHR 2.29 95% CI [2.20-2.39], P < 0.001) and history of prior amputation (LEB aHR 1.35 95% CI [1.17-1.56], P < 0.001; PVI aHR 1.5 95% CI [1.4-1.6], P < 0.001). CONCLUSIONS: Compared to NHW persons, Black persons present with more advanced vascular disease regardless of the operative indication. Black persons are also at significantly higher risk of 1-year MALE. Despite some advances in more accessible care through the ACA of 2014, our observations suggest that Black persons still have significantly worse outcomes due to variety of variables that need further investigation.

A systematic review of cognitive function after carotid endarterectomy in asymptomatic patients.

OBJECTIVE: Asymptomatic carotid stenosis has been associated with a progressive decline in neurocognitive function. However, the effect of carotid endarterectomy (CEA) on this process is poorly understood. We aimed to evaluate preoperative and postoperative cognitive function changes in asymptomatic patients after CEA. METHODS: A systematic review of the existing reports in PubMed/MEDLINE, Embase, and Cochran databases was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis statement recommendations. All original retrospective or prospective studies (including cohort, cross-sectional, case-control, pilot studies, etc) and clinical trials that compared pre and postoperative neurocognitive function in asymptomatic patients with carotid stenosis after CEA, which were published from January 2000 to April 2021 were identified and considered eligible for inclusion in the study. RESULTS: Thirteen studies (502 CEAs) comparing cognitive function changes before and after CEA were identified. In 7 studies with a total 272 patients, a mean age range of 67.3 ± 4.8 to 76.35 years old, and follow-up ranging between 1 and 12 months, overall cognitive function improved after CEA. However, in 6 studies with a total sample of 230, a mean age range of 68.6 ± 6.9 to 74.4 ± 6.1 years, and follow-up ranged from 24 hours to 3 years, showed no change or decline in overall cognitive function after procedures. CONCLUSIONS: The lack of standardization of specific cognitive tests and cognitive function assessment timing after CEA does not allow for definite conclusions to be made. However, improving brain perfusion with a combination of CEA and statin therapy may be a protective strategy against cognitive function decline.

Society for Vascular Surgery clinical practice guidelines for management of extracranial cerebrovascular disease.

Management of carotid bifurcation stenosis in stroke prevention has been the subject of extensive investigations, including multiple randomized controlled trials. The proper treatment of patients with carotid bifurcation disease is of major interest to vascular surgeons and other vascular specialists. In 2011, the Society for Vascular Surgery published guidelines for the treatment of carotid artery disease. At the time, several randomized trials, comparing carotid endarterectomy (CEA) and carotid artery stenting (CAS), were reported. Since the 2011 guidelines, several studies and a few systematic reviews comparing CEA and CAS have been reported, and the role of medical management has been reemphasized. In the present publication, we have updated and expanded on the 2011 guidelines with specific emphasis on five areas: (1) is CEA recommended over maximal medical therapy for low-risk patients; (2) is CEA recommended over transfemoral CAS for low surgical risk patients with symptomatic carotid artery stenosis of >50%; (3) the timing of carotid intervention for patients presenting with acute stroke; (4) screening for carotid artery stenosis in asymptomatic patients; and (5) the optimal sequence of intervention for patients with combined carotid and coronary artery disease. A separate implementation document will address other important clinical issues in extracranial cerebrovascular disease. Recommendations are made using the GRADE (grades of recommendation assessment, development, and evaluation) approach, as was used for other Society for Vascular Surgery guidelines. The committee recommends CEA as the first-line treatment for symptomatic low-risk surgical patients with stenosis of 50% to 99% and asymptomatic patients with stenosis of 70% to 99%. The perioperative risk of stroke and death in asymptomatic patients must be <3% to ensure benefit for the patient. In patients with recent stable stroke (modified Rankin scale score, 0-2), carotid revascularization is considered appropriate for symptomatic patients with >50% stenosis and should be performed as soon as the patient is neurologically stable after 48 hours but definitely <14 days after symptom onset. In the general population, screening for clinically asymptomatic carotid artery stenosis in patients without cerebrovascular symptoms or significant risk factors for carotid artery disease is not recommended. In selected asymptomatic patients with an increased risk of carotid stenosis, we suggest screening for clinically asymptomatic carotid artery stenosis as long as the patients would potentially be fit for and willing to consider carotid intervention if significant stenosis is discovered. For patients with symptomatic carotid stenosis of 50% to 99%, who require both CEA and coronary artery bypass grafting, we suggest CEA before, or concomitant with, coronary artery bypass grafting to potentially reduce the risk of stroke and stroke/death. The sequencing of the intervention depends on the clinical presentation and institutional experience.

Female Gender is a Predictor of Lower Iliac Vein Stenting Patency Rates.

BACKGROUND: Iliac venous stenting (IVS) for thrombotic and nonthrombotic venous disease is increasingly used as evidence of the safety, efficacy and durability of these interventions increases. Female gender has been implicated as a predictor of failure in arterial endovascular interventions. We hypothesize that female gender could be predictive of patency rates of iliac vein stenting. METHODS: Consecutive patients who underwent IVS for thrombotic or nonthrombotic venous disease at our institution from 2007 until 2019 were identified and divided into groups based on gender. Operative notes, venograms, and the electronic health record were then queried to obtain operative details, co-morbid conditions, postoperative outcomes and stent patency. Study outcome was long term patency rate. The data was analyzed using chi-square, logistic regression, and Kaplan-Meier analysis as appropriate. RESULTS: A total of 200 consecutive patients (231 limbs) were identified in our retrospective analysis, with a mean age of 48.8 ± 17.3, and BMI of 31.6 ± 8.6. Of those, 119 (59.5%) patients, (131 [56.8%] limbs) were female. Comparisons between the gender groups revealed no difference in age, BMI, or preoperative comorbidities. There was no difference in type of venous disease between male (85% thrombotic, 15% nonthrombotic) and female (84% thrombotic, 16% nonthrombotic), P= 0.830. The male cohort was more likely to present with leg ulceration (17% vs. 4.6%, P = 0.002), and the female cohort was more likely to present with leg edema (98.5% vs. 93.0%, P= 0.03). The male cohort had a higher rate of caval (48% vs. 33.6%, P= 0.027) and infrainguinal stent extension. (11% vs. 6.9%, P= 0.02). Females had a higher rate of left sided stenting (80.9% vs. 66/0%, P= 0.010). There was no difference in the median stent diameter used between the cohorts. Primary patency at 5 years was significantly higher for the male cohort (94.1% vs. 74.4%, P= 0.01) On adjusted multivariable cox regression female gender was a predictor of loss of primary patency within 5 years (HR, 4.04; P= 0.007). CONCLUSIONS: In this single center retrospective analysis of IVS, male patients were found to have better primary stent patency compared to female.

Cost-effectiveness analysis of immediate access arteriovenous grafts versus standard grafts for hemodialysis.

OBJECTIVE: Immediate-access arteriovenous grafts (IAAVGs), or early cannulation arteriovenous grafts (AVGs), are more expensive than standard grafts (sAVGs) but can be used immediately after placement, reducing the need for a tunneled dialysis catheter (TDC). We hypothesized that a decrease in TDC-related complications would make IAAVGs a cost-effective alternative to sAVGs. METHODS: We constructed a Markov state-transition model in which patients initially received either an IAAVG or an sAVG and a TDC until graft usability; patients were followed through multiple subsequent access procedures for a 60-month time horizon. The model simulated mortality and typical graft- and TDC-related complications, with parameter estimates including probabilities, costs, and utilities derived from previous literature. A key parameter was median time to TDC removal after graft placement, which was studied under both real-world (7 days for IAAVG and 70 days for sAVG) and ideal (no TDC placed with IAAVG and 1 month for sAVG) conditions. Costs were based on current Medicare reimbursement rates and reflect a payer perspective. Both microsimulation (10,000 trials) and probabilistic sensitivity analysis (10,000 samples) were performed. The willingness-to-pay threshold was set at $100,000 per quality-adjusted life-year (QALY). RESULTS: IAAVG placement is a dominant strategy under both real-world ($1201.16 less expensive and 0.03 QALY more effective) and ideal ($1457.97 less expensive and 0.03 QALY more effective) conditions. Under real-world parameters, the result was most sensitive to the time to TDC removal; IAAVGs are cost-effective if a TDC is maintained for ≥23 days after sAVG placement. The mean catheter time was lower with IAAVG (3.9 vs 8.7 months; P < .0001), as was the mean number of access-related infections (0.55 vs 0.74; P < .0001). Median survival in the model was 29 months. Overall mortality was similar between groups (76.3% vs 76.7% at 5 years; P = .33), but access-related mortality trended toward improvement with IAAVG (6.1% vs 6.8% at 5 years; P = .052). CONCLUSIONS: The Markov decision analysis model supported our hypothesis that IAAVGs come with added initial cost but are ultimately cost-saving and more effective. This apparent benefit is due to our prediction that a decreased number of catheter days per patient would lead to a decreased number of access-related infections.

Poor runoff and distal coverage below the knee are associated with poor long-term outcomes following endovascular popliteal aneurysm repair.

OBJECTIVE: Reports of good short-term outcomes for endovascular repair of popliteal artery aneurysms have led to an increased use of the technique. However, data are lacking on long-term limb-related outcomes and factors associated with the failure of endovascular repair. METHODS: All patients who underwent endovascular popliteal aneurysm repair (EPAR) at a single institution from January 2006 to December 2018 were included in the study. Demographics, indications, anatomic and operative details, and outcomes were reviewed. Long-term patency, major adverse limb event-free survival (MALE-FS) and graft loss/occlusion were analyzed with multivariable cox regression analysis and Kaplan-Meier curves. RESULTS: We included 117 limbs from 101 patients with a mean follow-up of 55.6 months (range, 0.43-158 months). The average age was 73 ± 9.3 years. Thirty-two patients (29.1%) were symptomatic (claudication, rest pain, tissue loss, or rupture). The stent grafts crossed the knee joint in 91.4% of cases. In all, 36.8% of procedures used one stent graft, 41.0% used two stent grafts, and 22.2% of procedures used more than two stent grafts. The median arterial length covered was 100 mm, with an average length of stent overlap of 25 mm. Tapered configurations were used in 43.8% of cases. The majority of limbs (62.8%) had a three-vessel runoff, 20.2% had a two-vessel runoff, and 17% has a one-vessel runoff. The Kaplan-Meier estimates of graft occlusion at 1 and 3 years were 6.3% and 16.2%, respectively. The 1- and 3-year primary patency rates were 88.2% and 72.6%, and the 1- and 3-year major adverse limb event-free survival (MALE-FS) rates were 82% and 57.4%. The 1- and 3-year survival rates were 92.9% and 76.2%, respectively. On multivariable Cox regression, aneurysm size, one-vessel runoff, and coverage below the knee were associated with a lower 3-year MALE-FS. Coverage below the knee was also associated with a lower 3-year MALE-FS. Other anatomic or technical details were not associated with limb-related events or patency. CONCLUSIONS: This study is the largest single center analysis to describe the predictors of poor outcomes after EPAR. EPAR is a safe and effective way to treat popliteal artery aneurysms. Factors associated with poor MALE-FS after EPAR include single-vessel tibial runoff and coverage below the knee.

Association of Medicaid Expansion with In-Hospital Outcomes After Abdominal Aortic Aneurysm Repair.

OBJECTIVES: Multiple studies have shown improved outcomes and higher utilization of care with the increase of insurance coverage. This study aims to assess whether Medicaid expansion (ME) has changed the utilization and outcomes of abdominal aortic aneurysm (AAA) repair in the United States. DESIGN: Retrospective observational study. MATERIALS: Data of patients undergoing AAA repair in the Vascular Quality Initiative (2010-2017). METHODS: Interrupted time-series (ITS) analysis was utilized to evaluate changes in annual trends of postoperative outcomes after elective AAA repair before and after 2014. We also assessed if these trend changes were significant by comparing the changes in states which adopted ME in 2014 versus nonexpansion states (NME), and conducting a difference-in-difference analysis. Primary outcomes included in-hospital mortality and adverse events (bowel and leg ischemia, cardiac, renal, respiratory, stroke and return to the OR). RESULTS: A total of 19,143 procedures were included (Endovascular: 85.8% and open: 14.2%), of which 40.9% were performed in ME States. Compared to preexpansion trends (P1), there was a 2% annual increase in elective AAA repair in ME states (P1: -1.8% versus P2: +0.2%, P< 0.01) with no significant change in NME (P1: +0.3% versus P2: +0.2%, P = 0.97). Among elective cases, annual trends in the use of EVAR increased by 2% in ME states (95% confidence interval (CI) = -0.1, 4.1, P = 0.06), compared to a 3% decrease in NME States [95%CI = -5.8, -0.6, P = 0.01) (PMEversusNME < 0.01]. There was no association between ME and in-hospital mortality. Nonetheless, it was associated with a decrease in the annual trends of in-hospital complications (ME: -1.4% (-2.1,-0.8) versus NME: +0.2% (-0.2, +0.8), P < 0.01). CONCLUSIONS: While no association between ME and increased survival was noted in states which adopted ME, there was a significant increase of elective AAA cases and EVAR utilization and a decrease in in-hospital complications in ME States.

Association of Abdominal Aortic Aneurysm and Simple Renal Cysts: A Systematic Review and Meta-Analysis.

BACKGROUND-OBJECTIVE: Prior studies have suggested a higher prevalence of simple renal cysts (SRC) among patients with aortic disease, including abdominal aortic aneurysms (AAA). Thus, the aim of this study was to systematically review all currently available literature and investigate whether patients with AAA are more likely to have SRC. METHODS: This study was performed according to the PRISMA guidelines. A meta-analysis was conducted with the use of random effects modeling and the I-square was used to assess heterogeneity. Odds ratios (OR) and the corresponding 95% confidence intervals (CI) were synthesized to compare the prevalence of several patients' characteristics between AAA vs. no-AAA cases. RESULTS: Eleven retrospective studies, 9 comparative (AAA vs. no-AAA groups) and 3 single-arm (AAA group), were included in this meta-analysis, enrolling patients (AAA: N = 2,297 vs. no-AAA: N = 35,873) who underwent computed tomography angiography as part of screening or preoperative evaluation for reasons other than AAA. The cumulative incidence of SRC among patients with AAA and no-AAA was 55% (95% CI: 49%-61%) and 32% (95% CI: 22%-42%) respectively, with a statistically higher odds of SRC among patients with AAA (OR: 3.02; 95% CI: 2.01-4.56; P< 0.001). The difference in SRC prevalence remained statistically significant in a sensitivity analysis, after excluding the study with the largest sample size (OR: 2.71; 95% CI: 1.91-3.84; P< 0.001). CONCLUSIONS: Our meta-analysis demonstrated a 3-fold increased prevalence of SRC in patients with AAA compared to no-AAA cases, indicating that the pathogenic processes underlying SRC and AAA could share a common pathophysiologic mechanism. Thus, patients with SRC could be considered at high risk for AAA formation, potentially warranting an earlier AAA screening.

Utilization and Outcomes of Radial Artery Access for Lower Extremity Endovascular Intervention.

INTRODUCTION: Radial artery access has become popular for cardiac interventions, but its role in lower extremity interventions is not well defined. We aimed to describe current utilization and outcomes of transradial access for lower extremity interventions. METHODS: Peripheral vascular intervention (PVI) from 2016-2020 where transradial access was employed in the Vascular Quality Initiative (VQI) registry were studied. Cases before 2016 were excluded as documentation of transradial access was not possible in earlier years. PVIs involving radial artery access were evaluated with regard to access guidance, access-site complications, target vessels treated and the technical success of these interventions. RESULTS: Of 167,098 PVIs, 1,096 (0.66%) involved radial access. Utilization varied significantly by region (P < 0.01). The left radial artery was used in 66.9% of cases. Ultrasound-guided access was documented in 72.7% of cases. There were no significant differences in age, body mass index, or sex between the transradial group and other PVIs. In 450 procedures, a second access site was utilized, most commonly a retrograde femoral access (60.0%) or retrograde pedal access (16.7%). The largest sheath was 6-Fr in 78.0%. Interventions documenting radial-only access more commonly treated the aortoiliac segment (49.4% vs. 29.5%, P < 0.001) and less commonly treated the tibial segments (7.1% vs. 32.1%, P < 0.001). Technical success was 94.0%, with inability to cross the lesion (3.1%) and residual stenosis after treatment (2.2%) being most common. There were access-site complications in 2.9%, with hematoma (2.4%) being most common. DISCUSSION: Radial access is associated with high technical success rates and low access-site complication rates. Advances in device profile and shaft length may overcome shortcomings of transradial access and lead to further utilization of this access site.

Complete Venous Ulceration Healing after Perforator Ablation Does Not Depend on Treatment Modality.

BACKGROUND: Venous leg ulceration (VLU) represents the most advanced form of chronic venous insufficiency (CVI). Persistent VLU that fails to respond to noninvasive treatment requires a minimally invasive endovascular treatment, which may include chemical (ultrasound-guided foam sclerotherapy [UGFS]) and thermal ablation (endovenous laser therapy [EVLT] or radiofrequency ablation [RFA]) targeting incompetent veins. Current guidelines suggest ablation of incompetent perforating veins (IPVs) juxtaposed to active or healed VLU; however, the ideal treatment modality is unknown. We hypothesize that similar to incompetent superficial vein treatment options therapies, VLU healing will be equivalent across minimally invasive IPV treatment options. METHODS: Using the Vascular Low Frequency Disease Consortium, adults with VLU across 11 medical centers were retrospectively reviewed (2013-2017). We included those who underwent IPV therapies. The primary outcome was complete ulcer healing over time compared with cumulative hazard curves, log-rank testing, and multivariable Cox proportional hazard regression. Secondary outcomes included number of subsequent procedures, which were compared using negative binomial regression. RESULTS: Of the 832 adults with VLU, 158 (19%) were exclusively treated conservatively, and 232 (28%) underwent index treatment for IPV and constitute the full and final cohort. The mean age was 60 ± 14 years, 57% were men, and the mean ulcer area was 3.0 cm2 (interquartile range, 1-6 cm2). Ninety-one (39%) were treated with EVLT, 127 (55%) RFA, and 14 (6%) UGFS. Patients treated with RFA were older (RFA 62 ± 14 years; EVLT 59 ± 14 years; UGFS 52 ± 9 years; P = 0.01), more likely to be men (RFA 68%, n = 86; EVLT 41%, n = 37; UGFS 64%, n = 9; P < 0.001), with a higher frequency of anticoagulation (RFA 36%, n = 46; EVLT 18%, n = 16; UGFS 14%, n = 2; P = 0.005). VLU did not significantly differ in size between groups (RFA 6.2 ± 8; EVLT 4.2 ± 5.4; UGFS 6.1 ± 8; P < 0.001). There were no differences in 1-year ulcer healing rates between groups (P = 0.18). The number of subsequent procedures did not differ by treatment modality (P = 0.47). CONCLUSIONS: This multi-institutional retrospective study does not demonstrate any association of IPV treatment modality with differing rates of VLU healing or number of subsequent procedures.

External validation of the Vascular Study Group of New England carotid endarterectomy risk predictive model using an independent U.S. national surgical database.

OBJECTIVE: Previously, we described a Vascular Study Group of New England (VSGNE) risk predictive model to predict composite adverse outcomes (postoperative death, stroke, myocardial infarction, or discharge to extended care facilities) after carotid endarterectomy (CEA). The goal of this study was to externally validate this model using an independent database. METHODS: The American College of Surgeons National Surgical Quality Improvement Program (NSQIP) CEA-targeted database (2010-2014) was used to externally validate the risk predictor model of adverse outcomes after CEA previously created using the VSGNE carotid database. Emergent cases and those in which CEA was combined with another operation were excluded. Cases in which a discharge destination cannot be determined were also excluded. To assess the predictive power of our VSGNE prediction score within this sample, a receiver operating characteristic curve was constructed. Risk scores for each NSQIP patient were also computed using beta weights from the VSGNE CEA model. To further assess the construct validity of our VSGNE prediction score, the observed proportion of adverse outcomes was examined at each level of our prediction scale and within five roughly equally sized risk groups formed on the basis of our VSGNE prediction scores. RESULTS: In this database, 10,889 cases met our inclusion criteria and were used in this analysis. The overall rate of adverse outcomes in this cohort was 8.5%. External validation of the VSGNE model on this sample showed moderately good predictive ability (area under the curve = 0.745). Patients in progressively higher risk groups, based on their VSGNE model scores, exhibited progressively higher rates of observed adverse outcomes, as predicted. CONCLUSIONS: The VSGNE CEA risk predictive model was externally validated on an NSQIP CEA-targeted sample and showed a fairly accurate global predictive ability for adverse outcomes after CEA. Although this model has a good population concordance, the lack of cut point indicates that individual risk prediction requires more evaluation. Further studies should be geared toward identification of variables that make this risk predictive model more robust.

Novel bypass risk predictive tool is superior to the 5-Factor Modified Frailty Index in predicting postoperative outcomes.

OBJECTIVE: This study aimed to develop risk predictive models of 30-day mortality, morbidity, and major adverse limb events (MALE) after bypass surgery for aortoiliac occlusive disease (AIOD) and to compare their performances with a 5-Factor Frailty Index. METHODS: The American College of Surgeons National Surgical Quality Improvement Program 2012-2017 Procedure Targeted Aortoiliac (Open) Participant Use Data Files were queried to identify all patients who had elective bypass for AIOD: femorofemoral bypass, aortofemoral bypass, and axillofemoral bypass (AXB). Outcomes assessed included mortality, major morbidity, and MALE within 30 days postoperatively. Major morbidity was defined as pneumonia, unplanned intubation, ventilator support for >48 hours, progressive or acute renal failure, cerebrovascular accident, cardiac arrest, or myocardial infarction. Demographics, comorbidities, procedure type, and laboratory values were considered for inclusion in the risk predictive models. Logistic regression models for mortality, major morbidity and MALE were developed. The discriminative ability of these models (C-indices) were compared with that of the 5-Factor Modified Frailty Index (mFI-5): a general frailty tool determined from diabetes, functional status, history of chronic obstructive pulmonary disease, history of congestive heart failure, and hypertension. Calculators were derived using the most significant variables for each of the three risk predictive models. RESULTS: A total of 2612 cases (mean age 65.0, 60% male) were identified, of which 1149 (44.0%) were femorofemoral bypass, 1138 (43.6%) were aortofemoral bypass, and 325 (12.4%) were axillofemoral bypass. Overall, the rates of mortality, major morbidity, and MALE were 2.0%, 8.5%, and 4.9%, respectively. Twenty preoperative risk factors were considered for incorporation in the risk tools. Apart from procedure type, age was the most statistically significant predictor of both mortality and morbidity. Preoperative anemia and critical limb ischemia were the most significant predictors of MALE. All three constructed models demonstrated significantly better discriminative ability (P < .001) on the outcomes of interest as compared with the mFI-5. CONCLUSIONS: Our models outperformed the mFI-5 in predicting 30-day mortality, major morbidity, and adverse limb events in patients with AIOD undergoing elective bypass surgery. Calculators were created using the most statistically significant variables to help calculate individual patient's postoperative risks and allow for better informed consent and risk-adjusted comparison of provider outcomes.

Comparable Patency of Open and Hybrid Treatment of Venous Anastomotic Lesions in Thrombosed Haemodialysis Grafts.

OBJECTIVE: Arteriovenous graft (AVG) failures are typically associated with venous anastomotic (VA) stenosis. Current evidence regarding AVG thrombosis management compares surgical with purely endovascular techniques; few studies have investigated the "hybrid" intervention that combines surgical balloon thrombectomy and endovascular angioplasty and/or stenting to address VA obstruction. This study aimed to describe outcomes after hybrid intervention compared with open revision (patch venoplasty or jump bypass) of the VA in thrombosed AVGs. METHODS: Retrospective cohort study. Consecutive patients with a thrombosed AVG who underwent thrombectomy between January 2014 and July 2018 were divided into open and hybrid groups based on VA intervention; patients who underwent purely endovascular thrombectomy were excluded. Patient demographics, previous access history, central vein patency, AVG anatomy, type of intervention, and follow up data were recorded. Kaplan-Meier curves were used to analyse time from thrombectomy to first re-intervention (primary patency) and time to abandonment (secondary patency). Cox regression analysis was performed to evaluate predictors of failure. RESULTS: This study included 97 patients (54 females) with 39 forearm, 47 upper arm, and 11 lower extremity AVGs. There were 34 open revisions (25 patches, nine jump bypasses) and 63 hybrid interventions, which included balloon angioplasty ± adjunctive procedures (15 stents, five cutting balloons). Technique selection was based on physician preference. Primary patency for the open and hybrid groups was 27.8% and 34.2%, respectively, at six months and 17.5% and 12.9%, respectively, at 12 months (p = .71). Secondary patency was 45.1% and 38.5% for open and hybrid treatment, respectively, at 12 months (p = .87). An existing VA stent was predictive of graft abandonment (hazard ratio 4.4, 95% confidence interval 1.2-16.0; p = .024). Open vs. hybrid intervention was not predictive of failure or abandonment. CONCLUSION: Hybrid interventions for thrombosed AVGs are not associated with worse patency at six and 12 months compared with open revision.

Impact of Medicaid Expansion of the Affordable Care on the Outcomes of Lower Extremity Bypass for Patients With Peripheral Artery Disease in the Vascular Quality Initiative Database.

OBJECTIVE: The aim of this study was to evaluate changes in the utilization and outcomes of surgery after Medicaid Expansion (ME) for patients with peripheral artery disease (PAD). SUMMARY BACKGROUND DATA: Recent studies have demonstrated increased insurance coverage and improved care with the Affordable Care Act's (ACA) state expansion of Medicaid. METHODS: Infrainguinal bypass procedures performed due to occlusive pathology in the Vascular Quality Initiative database between 2010 and 2017 were included. Primary outcomes including postoperative mortality and major adverse limb events (MALE) at 1-year of follow-up were analyzed using interrupted time-series analysis (ITS). RESULTS: Out of 26,446 infrainguinal bypass procedures, 13,955 (52.8%) were included in this analysis. ME states witnessed an annual decrease in infrainguinal surgery for acute ischemia [annual change in post vs pre-ME period (95% confidence interval): -4.3% (-7.5% to -1.0%), P = 0.02] and an increase in revascularization for claudication [3.7% (1.7%-5.6%), P = 0.01]. Among nonacute cases, elective procedures increased in ME states [3.9% (0.1%-7.7%), P = 0.05] along with a significant annual decrease in in-hospital mortality [-0.4% (-0.8 to -0.02), P = 0.04) and MALE at 1 year of follow up [-9.0% (-20.3 to 2.3), P = 0.09]. These results were statistically significant after comparing them with the annual trend changes in states which did not adopt ME. CONCLUSIONS: The adoption of ME in 2014 was associated with significant increase in the use of infrainguinal bypass for nonsevere and elective cases, along with improved in-hospital mortality and MALE at 1 year. Longer follow-up is needed to evaluate the impact of ME on other aspects of care and longer term outcomes of PAD patients.

Role of nutritional indices in predicting outcomes of vascular surgery.

BACKGROUND: Malnutrition is frequent among vascular surgery patients, given their age, chronic comorbidities, and poor functional status, and it is believed to increase their operative risk. We aimed to assess the combined use of recent significant weight loss (>10% body mass) and serum albumin levels as a nutritional status index to predict outcomes. METHODS: We analyzed vascular surgery data from the American College of Surgeons National Surgical Quality Improvement Program database (2005-2012; N = 238,082) to compare operative death (in-hospital and 30-day operative death) across eight nutritional status groups based on weight loss (yes/no) and albumin category: very low albumin level (VL-Alb; <2.50 g/dL), low albumin level (L-Alb; 2.50-3.39 g/dL), normal albumin level (N-Alb; 3.40-4.39 g/dL), and high albumin level (H-Alb; 4.40-5.40 g/dL). Risk-adjusted odds ratios (AOR) with 95% confidence intervals were estimated by multivariable logistic regression (N-Alb [no weight loss], reference). RESULTS: The study population included 113,936 patients for whom albumin level was available (age, 67 ± 13 years; 60.2% male). Operative death was documented in 5160 (4.53%) patients. The eight-category nutritional status was more predictive of operative death than age alone (C statistic, 0.74 vs 0.63). A high discrimination multivariable model for operative death was derived (C statistic, 0.851). Low albumin level was associated with increased death that worsened in case of weight loss: VL-Alb + WL, AOR = 3.83 (3.03-4.83); VL-Alb, AOR = 3.36 (3.06-3.69); L-Alb + WL, AOR = 2.46 (1.98-3.05); and L-Alb, AOR = 1.99 (1.84-2.15). Weight loss was associated with increased death even if albumin level was normal: N-Alb + WL, AOR = 1.77 (1.34-2.35); and H-Alb + WL, AOR = 1.91 (0.69-5.31). H-Alb was protective (AOR = 0.65 [0.55-0.76]). CONCLUSIONS: Nutritional status predicts outcomes of vascular surgery. Serum albumin level and weight loss should be incorporated in patients' risk stratification.

Immediate-access grafts provide comparable patency to standard grafts, with fewer reinterventions and catheter-related complications.

BACKGROUND: No independent comparisons, with midterm follow-up, of standard arteriovenous grafts (SAVGs) and immediate-access arteriovenous grafts (IAAVGs) exist. The goal of this study was to compare "real-world" performance of SAVGs and IAAVGs. METHODS: Consecutive patients who underwent placement of a hemodialysis graft between November 2014 and April 2016 were retrospectively identified from the electronic medical record and Vascular Quality Initiative database at two tertiary centers. Only primary graft placements were included for analysis. Patients were divided into two groups based on the type of graft implanted. Patients' comorbidities, graft configuration, operative characteristics, and follow-up were collected and analyzed with respect to primary and secondary patency. Additional outcomes included graft-related complications, time to first cannulation, time to tunneled catheter removal, catheter-related complications, and overall survival. Patency was determined from the time of the index procedure; χ2, Kaplan-Meier, and Cox regression analyses were used, with the P value set as significant at < .05. RESULTS: There were 210 grafts identified, 148 SAVGs and 62 IAAVGs. At baseline, the patients' characteristics were similar between groups, except for a greater prevalence of preoperative central venous occlusions in the IAAVG group (16.3% vs 6.8%; P < .04). Of the IAAVG group, 50 were Acuseal (W. L. Gore & Associates, Flagstaff, Ariz) and 12 were Flixene (Atrium Medical Corporation, Hudson, NH). Primary patency was similar at both 1 year (SAVG, 39.4%; IAAVG, 56.7%; P = .4) and 18 months (SAVG, 29.0%; IAAVG, 43.7%; P = .4). Secondary patency was similar at 1 year (SAVG, 50.7%; IAAVG, 52.1%; P = .73) and 18 months (SAVG, 42.3%; IAAVG, 46.3%; P = .73). Overall survival was 48% at 24 months. IAAVG patients required fewer overall additional procedures to maintain patency (mean number of procedures, 0.99 for SAVGs vs 0.61 for IAAVGs; P = .025). There was no difference in occurrence of steal syndrome (SAVG, 6.8%; IAAVG, 8.1%; P = .74) or graft infection (SAVG, 19.0%; IAAVG, 12.0%; P = .276). Seventy-five percent of all grafts were successfully cannulated, with shorter median time to first cannulation in the IAAVG group (6 days; interquartile range [IQR], 1-19 days) compared with the SAVG group (31 days; IQR, 26-47 days; P < .01). Of all pre-existing catheters, 65.75% were removed, with a shorter median time until catheter removal in the IAAVG cohort at 34 days (IQR, 22-50 days) vs 49 days (IQR, 39-67 days) in the SAVG group (P < .01). Catheter-related complications occurred less frequently in the IAAVG group (16.4% vs 2.9%; P < .045). CONCLUSIONS: IAAVGs allow earlier cannulation and tunneled catheter removal, thereby significantly decreasing catheter-related complications. Patency and infection rates were similar between SAVGs and IAAVGs, but fewer secondary procedures were performed in IAAVGs.

Editor's Choice - Comparison of Outcomes After Open Surgical and Endovascular Lower Extremity Revascularisation Among End Stage Renal Disease Patients on Dialysis.

OBJECTIVES: End stage renal disease (ESRD) patients with peripheral arterial disease (PAD) are at high risk of complications following open surgical revascularisation (OSR). Endovascular revascularisation (ER) is an option, but its role is unclear. This study sought to characterise the outcomes of ER and OSR in ESRD patients treated for claudication or critical limb ischaemia (CLI). METHODS: The United States Renal Data System was used to investigate outcomes after lower extremity ER and OSR from 2005 to 2011. Primary outcomes were mortality, amputation, and peri-procedural myocardial infarction (MI). Kaplan-Meier (K-M) estimates were generated for mortality and amputation, logistic regression models for 30 day predictors, and proportional hazards models for long-term predictors. RESULTS: A total of 20,347 patients underwent OSR and ER (20.3% OSR, 79.7% ER). CLI was the indication in 80.8% of ER and 88.4% of OSR. The unadjusted major amputation rate at 30 days was higher after ER compared with OSR (8.8% vs. 6.4%, p < .001). Conversely, the unadjusted mortality rate at 30 days was lower after ER compared with OSR (8.0% vs. 10.5%, p < .001). Multivariable logistic regression models adjusting for medical covariables and CLI versus claudication status demonstrated increased 30 day mortality risk with OSR compared with ER (OR 2.00, 95% CI 1.43-1.79, p < .001), MI (OR 1.38, 1.23-1.54, p < .001), and the combined endpoint of mortality and major amputation (OR 1.57, 1.16-2.12, p = .004), but lower odds of 30 day major amputation alone (OR 0.67, 0.58-0.77, p < .001). Proportional hazards models demonstrated increased long-term mortality risk with OSR compared with ER (HR 1.05, 1.00-1.09, p = .037), without a difference in major amputation (HR 0.99, 0.93-1.05, p = NS). CONCLUSIONS: In this retrospective analysis of an administrative database, ESRD patients suffer from high mortality and amputation rates following lower extremity revascularisation. Compared with ER, OSR is associated with higher mortality. OSR has better 30 day limb salvage, although long-term outcomes are similar.

Trends and Outcomes of Pediatric Vascular Injuries in the United States: An Analysis of the National Trauma Data Bank.

BACKGROUND: According to the Center for Disease Control and Prevention, trauma is the leading cause of death in children aged >1 year in the United States (US). Although vascular injuries occur in only 0.6-1% of pediatric patients with trauma, they are a major mortality contributor. This study aims to examine epidemiology and outcomes after pediatric vascular injuries (PedVIs) in the US. METHODS: The National Trauma Data Bank (2002-2012) was queried to identify children (0-16) with PedVIs. Patients were categorized based on their demographics, location, and mechanism and presenting trauma severity (injury severity score [ISS] and shock). Study was divided into two 5-year periods (P1: 2002-2006; P2: 2007-2012) to study the trends in pediatric vascular trauma presentation and outcomes (hospital death and extended length of stay [LOS > 8 days]) using adjusted analyses. RESULTS: Analyses were performed on 3,408 cases; who were male (73.7%) and Caucasian (52.8%) with a mean age of 10.5 ± 4.5 years. The Southern region of the US saw the highest increase in PedVIs (P2 versus P1: 38.3% vs. 25.0%, P < 0.05). Blunt injuries constituted most of these injuries (57%). Firearm (36.9%) and motor vehicle crash (MVC) (34%) were the most common lethal mechanisms of injury. Despite the significant decrease in MVC rates (P2 versus P1: 17.4% vs. 22.6%, P < 0.05), firearm rates were unchanged. Upper extremity injuries were the most common anatomically (34.9%). ISS and shock were significantly decreased during P2. Mortality occurred in 7.9% of patients, which significantly decreased (P2 versus P1: 6.3% vs. 10.9%, P < 0.001) without a significant change in LOS. Odds of mortality decreased by 32% during P2 (P = 0.08) and was independently associated with penetrating mechanism of injury (odds ratio [OR]: 1.97; 95% confidence interval [CI]: 1.22-3.19, P = 0.006), shock at presentation (OR: 5.48; 95% CI: 3.55-8.46, P < 0.001); ISS (OR: 1.08; 95% CI: 1.06-1.27, P < 0.001), and Glasgow Coma Score < 9 (OR: 11.21; 95% CI: 7.18-17.49, P < 0.001). CONCLUSIONS: We observed a significant decrease in the overall severity of injury and in-hospital mortality concurrent with the observation of a significant decrease in the rates of pediatric MVC vascular injuries. Public health policies directed toward firearm safety may further decrease PedVIs and mortality among this vulnerable population.