Reassuring Intraoperative Parameters Do Not Obviate the Need for Infrainguinal Bypass Completion Angiograms.

OBJECTIVE: To determine if routine completion angiography for lower extremity bypasses using vein conduit results in lower rates of postoperative bypass occlusion. SUMMARY OF BACKGROUND DATA: With the increasing availability of on-table angiography and significant advancements in endovascular techniques, some operators routinely perform completion angiograms. The effect of this surgical paradigm has yet to be rigorously compared to the more widespread selective use of completion imaging in the modern era. METHODS: This retrospective cohort study included infrainguinal arterial bypass procedures utilizing vein conduit completed at a single hospital system from 2001 to 2018 and compared postoperative outcomes between bypasses that underwent routine completion angiography versus selective completion angiography. Notably, any bypasses that underwent completion angiography due to intraoperative concerns were excluded from this analysis. RESULTS: 666 bypasses that were performed in 589 patients met inclusion criteria. 126 (16.9%) bypasses were classified into the routine completion angiogram group compared to 540 (81.0%) into the selective completion angiogram group. Patients who underwent routine completion angiograms had a rate of intraoperative reintervention of 22.2%. The routine angiogram group had lower rates of reintervention (3.9% vs 10.0%, P = 0.03) and graft occlusion (2.3% vs 9.2%, P = 0.01) at 1-month postoperatively. CONCLUSION: Lower extremity bypasses using vein conduit that undergo routine completion angiography are associated with lower rates of graft occlusion at 30-days postoperatively. Completion angiography should thus be routinely performed in infrainguinal bypasses that utilize venous conduit.

Longer patient travel distance is associated with increased non-index readmission after complex aortic surgery.

OBJECTIVE: Recently evolving practice patterns in complex aortic surgery have led to regionalization of care within fewer centers in the United States, and thus patients may have to travel farther for complex aortic care. Travel distance has been associated with inferior outcomes after non-vascular surgery, particularly non-index readmission. This study aims to assess the impact of patient travel distance on perioperative outcomes and readmissions after complex aortic surgery. METHODS: A retrospective review was conducted of all patients in the Vascular Quality Initiative and Vascular Implant Surveillance and Interventional Outcomes Network databases undergoing complex endovascular aortic repair (EVAR) including internal iliac or visceral vessel involvement, complex thoracic endovascular aortic repair (TEVAR) including zone 0 to 2 proximal extent or branched devices, and complex open abdominal aortic aneurysm (AAA) repair including suprarenal or higher clamp sites. Travel distance was stratified by rural/urban commuting area (RUCA) population-density category. Wilcoxon and χ2 tests were used to assess relationships between travel distance quintiles and baseline characteristics, mortality, and readmission. Travel distance and other factors were included in multivariable Cox models for survival and Fine-Gray competing risk models for freedom from readmission. RESULTS: Between 2011 and 2018, 8782 patients underwent complex aortic surgery in the Vascular Quality Initiative and Vascular Implant Surveillance and Interventional Outcomes Network databases, including 4822 complex EVARs, 2672 complex TEVARs, and 1288 complex open AAA repairs. Median travel distance was 22.8 miles (interquartile range [IQR], 8.6-54.8 miles). Median age was 75 years for all distance quintiles, but patients traveling longer distances were more likely female (26.8% in quintile 5 [Q5] vs 19.9% in Q1; P < .001), white (93.8% of Q5 vs 83.8% of Q1; P < .001), to have larger-diameter AAAs (median 59 mm for Q5 vs 55 mm for Q1; P < .001), and to have had prior aortic surgery (20.8% for Q5 vs 5.9% for Q1; P < .001). Overall 30-day readmission was more common at farther distances (18.1% for Q5 vs 14.8% for Q1; P = .003), with higher non-index readmission (11.2% for Q5 vs 2.7% for Q1; P < .001) and conversely lower index readmission (6.9% for Q5 vs 12.0% for Q1; P < .001). Multivariable-adjusted Fine-Gray models confirmed greater hazard of non-index readmission with farther distance, with a Q5 hazard ratio of 3.02 (95% confidence interval, 2.12-4.30; P < .001). Multivariable-adjusted Cox models demonstrated no association between travel distance and long-term survival but found that non-index readmission was associated with increased long-term mortality (hazard ratio, 1.46; 95% confidence interval, 1.20-1.78; P = .0001). CONCLUSIONS: Patients traveling farther for complex aortic surgery demonstrate higher non-index readmission, which, in turn, is associated with increased long-term mortality risk. Aortic centers of excellence should consider targeting these patients for more comprehensive follow-up and care coordination to improve outcomes.

Partial and complete explantation of aortic endografts in the modern era.

OBJECTIVE: Despite the progressive advancement of devices for endovascular aortic repair (EVAR), endografts continue to fail, requiring explant. We present a single-institutional experience of EVAR explants, characterizing modern failure modes, presentation, and outcomes for partial and complete EVAR explantation. METHODS: A retrospective analysis was performed of all EVARs explanted at an urban quaternary center from 2001 to 2020, with one infected endograft excluded. Patient and graft characteristics, indications, and perioperative and long-term outcomes were analyzed. Partial versus complete explants were performed per surgeon discretion without a predefined protocol. This process was informed by patient risk factors; asymptomatic, symptomatic, or ruptured aneurysm presentation; and anatomical or intraoperative factors, including endoleak type. RESULTS: From 2001 to 2020, 52 explants met the inclusion and exclusion criteria. More than one-half (57.7%) were explants of EVAR devices placed at outside institutions, designated nonindex explants. Most patients were male (86.5%), the median age was 74 years (interquartile range, 70-78 years). More than one-half (61.5%) were performed in the second decade of the study period. The most commonly explanted grafts were Gore Excluder (n = 9 grafts), Cook Zenith (n = 8), Endologix AFX (n = 7), Medtronic Endurant (n = 5), and Medtronic Talent (n = 5). Most grafts (78.8%) were explanted for neck degeneration or sac expansion. Five were explanted for initial seal failure, five for symptomatic expansion, and seven for rupture. The median implant duration was 4.2 years, although ranging widely (interquartile range, 2.6-5.1 years), but similar between index and nonindex explants (4.2 years vs 4.1 years). Partial explantation was performed in 61.5%, with implant duration slightly lower, 3.2 years versus 4.4 years for complete explants. Partial explantation was more frequent in index explants (68.2% vs 56.7%). The median length of stay was 8 days. The median intensive care unit length of stay was 3 days, without significant differences in nonindex explants (4 days vs 3 days) and partial explants (4 days vs 3 days). Thirty-day mortality occurred in two nonindex explants (one partial and one complete explant). Thirty-day readmission was similar between partial and complete explants (9.7% vs 5.0%), without accounting for nonindex readmissions. Long-term survival was comparable between partial and complete explants in Cox regression (hazard ratio, 2.45; 95% confidence interval, 0.79-7.56; P = .12). CONCLUSIONS: Explants of EVAR devices have increased over time at our institution. Partial explant was performed in more than one-half of cases, per operating surgeon discretion, demonstrating higher blood loss, more frequent acute kidney injury, and longer intensive care unit stays, however with comparable short-term mortality and long-term survival.

Greater Patient Travel Distance is Associated with Perioperative and One-Year Cost Increases After Complex Aortic Surgery.

BACKGROUND: With increasing regionalization of complex aortic surgery within fewer US centers, patients may face increased travel burden when accessing aortic surgery. Longer travel distances have been associated with inferior outcomes after major surgery; however, the impacts of distance on reinterventions and costs have not been described. This study aims to assess the association between patient travel distance and longer-term outcomes including costs and reinterventions after complex aortic surgery. METHODS: A retrospective review was conducted of all patients in the Vascular Implant Surveillance and Interventional Outcomes Network database undergoing complex endovascular aortic repair including internal iliac or visceral vessel involvement, complex thoracic endovascular aortic repair including Zone 0-2 proximal extent or branched devices, and complex open abdominal aortic aneurysm repair including suprarenal or higher clamp sites. Travel distance was stratified by Rural-Urban Commuting Area population-density category. Multinomial logistic regression models, negative-binomial models, and zero-inflated Poisson models were used to assess the association between travel distance and index procedural and comprehensive first-year costs, long-term imaging, and long-term reinterventions, respectively. RESULTS: Between 2011 and 2018, 8,782 patients underwent complex aortic surgery in the Vascular Implant Surveillance and Interventional Outcomes Network database, including 4,822 complex endovascular aortic repairs, 2,672 complex thoracic endovascular aortic repairs, and 1,288 complex open abdominal aortic aneurysm repairs. Median travel distance was 22.8 miles (interquartile range 8.6-54.8 miles, range 0-2,688.9 miles). Median age was 75 years for all distance quintiles. Patients traveling farther were more likely to be female (26.8% in quintile 5 [Q5] vs. 19.9% in Q1, P < 0.001) and to have had a prior aortic surgery (20.8% for Q5 vs. 5.9% for Q1, P < 0.001). Patients traveling farther had higher index procedural costs, with adjusted odds ratio (OR) 2.34 (95% confidence interval [CI] 1.86-2.94, P < 0.0001) of being in the highest cost tertile versus lowest for patients in Q5 vs. Q1. For patients with ≥ 1-year follow-up, those traveling farther had higher imaging costs, with adjusted Q5 OR 1.55 (95% CI 1.22-1.95, P = 0.0002), and comprehensive first-year costs, with adjusted Q5 OR 2.06 (95% CI 1.57-2.70, P < 0.0001). In contrast, patients traveling farther had similar numbers of reinterventions and imaging studies postoperatively. CONCLUSIONS: Patients traveling farther for complex aortic surgery have higher procedural costs, postoperative imaging costs, and comprehensive first-year costs. These patients should be targeted for increased care coordination for improved outcomes and healthcare system burden.

Utility of Hook Sign in the Diagnosis of Median Arcuate Ligament Syndrome.

BACKGROUND: Median arcuate ligament syndrome (MALS) is a clinical syndrome caused by compression of the celiac artery by the median arcuate ligament that often manifests with nonspecific abdominal pain. Identification of this syndrome is often dependent on imaging of compression and upward bending of the celiac artery by lateral computed tomography angiography, the so-called "hook sign." The purpose of this study was to assess the relationship of radiologic characteristics of the celiac artery to clinically relevant MALS. METHODS: An institutional review board-approved retrospective chart review from 2,000 to 2,021 of 293 patients at a tertiary academic center diagnosed with celiac artery compression (CAC) was performed. Patient demographics and symptoms of 69 patients who were diagnosed with symptomatic MALS were compared to 224 patients without MALS (but with CAC) per electronic medical record review. Computed tomography angiography images were reviewed and the fold angle (FA) was measured. The presence of a hook sign (defined as a visual FA < 135°), as well as stenosis (defined as >50% of luminal narrowing on imaging) were recorded. Wilcoxon rank-sum test and Chi-squared test were used for comparative analysis. Logistic model was run to relate the presence of MALS with comorbidities and radiographic findings. RESULTS: Imaging was available in 59 patients (25 males, 34 females) and 157 patients (60 males, 97 females) with and without MALS, respectively. Patients with MALS were more likely to have a more severe FA (120.7 ± 33.6 vs. 134.8 ± 27.9, P = 0.002). Males with MALS were also more likely to have a more severe FA compared with males without MALS (111.1 ± 33.7 vs. 130.4 ± 30.4, P = 0.015). In patients with body mass index (BMI) >25, MALS patients also had narrower FA compared with patients without MALS (112.6 ± 30.5 vs. 131.7 ± 30.3, P = 0.001). The FA was negatively correlated with BMI in patients with CAC. The hook sign and stenosis were associated with diagnosis of MALS (59.3% vs. 28.7%, P < 0.001, and 75.7% vs. 45.2%, P < 0.001, respectively). In logistic regression, pain, stenosis, and a narrow FA were statistically significant predictors of the presence of MALS. CONCLUSIONS: The upward deflection of the celiac artery in patients with MALS is more severe compared with patients without MALS. Consistent with prior literature, this bending of the celiac artery is negatively correlated with BMI in patients with and without MALS. When demographic variables and comorbidities are considered, a narrow FA is a statistically significant predictor of MALS. Regardless of MALS diagnosis, a hook sign was associated with narrower FA. While demographics and imaging findings may inform MALS diagnosis, clinicians should not rely on a visual assessment of a hook sign but should quantitatively measure the anatomic bending angle of the celiac artery to assist with the diagnosis and understand the outcomes.

Differences in Aortic Intramural Hematoma Contrast Attenuation on Multi-Phase CTA Predict Long-Term Aortic Morphologic Change.

BACKGROUND: Evolution of aortic intramural hematoma (IMH) over time may range from resolution to degeneration and is difficult to predict. We sought to measure differences in contrast attenuation between arterial and delayed phase computed tomography angiography (CTA) images within the IMH as a surrogate of hematoma blood flow to predict resolution versus aortic growth and/or adverse outcomes. METHODS: IMH institutional data were gathered from 2005-2020. Hounsfield unit ratio (HUR) was measured as hematoma Hounsfield unit (HU), on delayed phase images divided by HU on arterial phase images on CTA. Aortic growth and effect of HUR was determined using a linear mixed effects model. Freedom from adverse aortic event, defined as the composite of intervention, recurrence of symptoms, radiographic progression, and rupture, was determined using Kaplan-Meier analysis. RESULTS: IMH occurred in 73 patients, of which 27 met the inclusion criteria. HUR ranged from 0.38-1.92 (mean: 0.98). Baseline aortic diameter growth independent of HUR measurement was 0.49 mm/year (95% confidence interval CI: -1.23 to 2.2). With the HUR was introduced into the model, the beta coefficient for time was -5.83 mm/year (95% CI: -10.4 to -1.28 mm/year) and the beta coefficient for the HUR was 5.05 mm/year per one-unit HUR (95% CI: 0.56 to 9.56 mm/year). Thus, an HUR>1.15 would correspond to aortic growth while an HUR<1.15 would correspond to reduction in aortic diameter, consistent with IMH resolution. Aortic adverse events occurred in 13 (48%) patients, 7 (26%) patients had recurrence of symptoms, 8 (30%) required intervention, 5 (18%) progressed to dissection, and 1(4%) had aortic rupture. There was a trend towards an association between higher HUR and composite adverse aortic events (HR 3.2 per 1-unit HUR; 95% CI: 0.6-17.3; P = 0.18). CONCLUSIONS: Increased HUR is associated with increased aortic growth and a trend toward adverse aortic events. Diminished delayed phase enhancement may predict partial or complete IMH resolution. HUR can be used to guide IMH surveillance and treatment.

Utilization of Thromboelastography with Platelet Mapping to Predict Infection and Poor Wound Healing in Postoperative Vascular Patients.

BACKGROUND: Postoperative infection and wound dehiscence rates are higher than expected in peripheral artery disease and contribute significantly to limb loss and mortality. Microvascular pathology characterized by microthrombi and increased platelet aggregation have been cited as contributing factors to poor wound healing and infection. The emergence of viscoelastic assays, such as thromboelastography with platelet mapping (TEG-PM), have been utilized to identify prothrombotic states and may provide insight into a patient's microvascular coagulation profile. This prospective, observational study aimed to determine if TEG-PM could predict poor wound healing or infection following lower extremity revascularization. METHODS: All patients undergoing revascularization between December 2020 and January 2022 were prospectively included and followed for wound complications or non-surgical site infections of the index limb. TEG-PM metrics at the first postoperative follow-up in the nonevent group was compared to the TEG-PM sample preceding the diagnosis of infection/dehiscence in the event group. Cox proportional hazards (PH) regression was used to model the predictive value of viscoelastic parameters. Cut-point analysis to determine high-risk groups was determined by performing receiver operating characteristic curve analysis. RESULTS: Of the 102 patients, 18.6% experienced infection/dehiscence. The TEG-PM sample analyzed in the event group was, on average, 19.5 days prior to the diagnosis of an event. The event group had significantly higher maximum clot amplitude (MA) (47.3 mm ± 16.0 vs. 30.6 mm ± 15.3, P < 0.01), higher platelet aggregation (71.3% ± 27.7 vs. 31.2% ± 24.0, P < 0.01), and lower platelet inhibition (28.7% ± 27.7 vs. 68.7% ± 24.1, P < 0.01). Cox PH analysis identified platelet aggregation as an independent and consistent predictor of infection (hazard ratio = 1.04, 95% confidence interval 1.03-1.06, P < 0.01). An optimal cut-point of > 33.2 mm MA, > 46.6% platelet aggregation, or < 55.8% platelet inhibition identifies those with infection/dehiscence with 79.0-89.5% sensitivity. CONCLUSIONS: These are the first data to provide a quantitative link between prothrombotic viscoelastic coagulation profiles with the development of infection/dehiscence. Based on the cut-points of > 33.2 mm MA, > 46.6% platelet aggregation, or < 55.8% platelet inhibition, we recommend consideration of an enhanced antimicrobial or antithrombotic approach for these high risk groups.

Unplanned readmissions after endovascular intervention or surgical bypass for critical limb ischemia.

OBJECTIVE: After surgery or other interventions, unplanned readmissions are associated with poor outcomes and drain health care resources. Patients with critical limb ischemia (CLI) are at particularly high risk of readmission, and readmissions result in increased health care costs. The primary aims of the study were to discover and compare the 30-day readmission rates of patients who underwent lower extremity surgical bypass (LEB) and endovascular infrainguinal endovascular intervention (IEI) for CLI and to evaluate the relationship between unplanned readmissions likely related to the primary procedure for IEI compared with LEB. METHODS: The Targeted Vascular Module from the American College of Surgeons National Surgical Quality Improvement Program was queried to identify all infrainguinal LEB or IEI for CLI from 2015 to 2018. Those who were not eligible for the primary outcome of interest were excluded. The primary 30-day outcome was unplanned readmission. Univariate analyses for primary and secondary outcomes were performed using Fisher's exact and Wilcoxon rank-sum testing. Multivariate analysis was performed using inverse probability weighting and independent risk factors for readmission were identified with logistic regression. RESULTS: There were 12,873 patients who met inclusion criteria. In the LEB cohort, there were 7270 (56.5%) patients, and in the IEI cohort, there were 5603 (43.5%) patients. Thirty percent (n = 1696) of the IEI cohort underwent a tibial intervention, and 49% (n = 3547) underwent a distal bypass. The IEI cohort was more likely to be high physiologic risk (P < .001) and to present with tissue loss (P < .001), whereas the LEB cohort was more likely to have high anatomic risk features (P < .001) and be performed under emergent conditions (P < .001). After multivariable analysis, LEB was found to be independently predictive for both unplanned readmissions due to any cause (adjusted odds ratio, 1.35; 95% confidence interval, 1.22-1.51; P < .001) and procedure-related unplanned interventions (adjusted odds ratio, 1.85; 95% confidence interval, 1.63-2.11; P < .001). Independent predictors of readmission were LEB, preoperative sepsis, severe chronic kidney disease, dependent functional status, insulin-dependent diabetes mellitus, high-risk physiologic features, African American race, preoperative steroid use, history of severe chronic obstructive pulmonary disease, and preoperative tissue loss. CONCLUSIONS: LEB is independently associated with unplanned readmission from all causes and from procedure-related causes after adjusting for the measured confounders. More research is required to determine the economic burden of these readmissions.

Natural history of penetrating atherosclerotic ulcers in aortic branch vessels.

OBJECTIVE: Penetrating atherosclerotic ulcers (PAUs) in aortic branch vessels are rare. There is a paucity of data regarding their long-term natural history and associated management. This study aimed to determine the prevalence and natural history of aortic branch PAUs. METHODS: Institutional data on all patients with an aortic branch PAU from 2005 to 2020 were retrospectively reviewed. Branch PAUs were defined as any PAU in the iliac, mesenteric, or arch vessels. End points included symptoms, end-organ events, and interventions. All computed tomography angiographies (CTAs) for each patient were reviewed, and total diameter, ulcer width, and ulcer depth were recorded on each computed tomography scan for the branch PAUs. Rate of change was compared between groups (iliac vs arch and visceral vessels) using a linear mixed-effects model. RESULTS: Among 58,800 patients who underwent a CTA, 367 patients had an aortic PAU (prevalence: 0.6%) and 58 patients had a branch PAU (prevalence: 0.1%). Among those 58 patients, there were 66 ulcerated branches. There were 50 iliac (42 common iliac, 7 internal, and 1 external), 11 arch (8 left subclavian, 3 innominate), and 5 visceral ulcers (3 superior mesenteric artery, 1 celiac, and 1 renal). Mean age was 74.0 ± 8.8 years, and 86% of patients were male; 74% had hypertension, 79% had hyperlipidemia, and 59% had a concomitant aortic aneurysm. There were 45 PAU vessels with >1 CTA (total of 167 CTAs) with a median follow-up of 4.0 years (interquartile range: 2.0-6.2 years). Total vessel diameter increased in size by 0.27 mm/y but did not differ between groups (iliac vs visceral/arch vessels). PAU width and depth also did not significantly change over time, nor did it differ between groups. No branch PAUs caused symptoms, end-organ events, or rupture, nor required intervention due to symptoms and/or progression. Four PAUs spontaneously resolved (2 iliac, 2 other), and 1 iliac PAU progressed to a saccular aneurysm. CONCLUSIONS: This is one of the largest studies evaluating the natural history of branched PAUs objectively via CTA. Branch PAUs are rare-the prevalence was one-sixth that of aortic PAUs. There was minimal growth noted in a median follow-up of 4 years, and no PAUs required intervention for symptoms or progression. Asymptomatic branch PAUs may be safely observed.

Effect of occult malignancy on femoropopliteal bypass graft thrombosis.

OBJECTIVE: The presence of cancer increases arterial thromboembolic events, specifically myocardial infarction and stroke, before a formal diagnosis of cancer. To the best of our knowledge, this increase in thrombotic risk has not been studied in patients with lower extremity bypass grafts. In the present study, we aimed to determine the effect of occult cancer on femoropopliteal bypass patency. METHODS: A retrospective review of femoropopliteal bypass procedures completed from 2001 to 2018 was performed. International Classification of Diseases, 9th and 10th revision, codes corresponding to breast, lung, prostate, colorectal, skin, brain, and hematologic cancer were used to identify patients who had had occult cancer. Occult cancer was defined as cancer diagnosed within ≤1 year after the bypass procedure. The demographics, comorbidities, bypass configuration and conduit, 1-month, 3-month, 6-month, and 1-year occlusion rates, major adverse limb events, and mortality rates were analyzed. Statistical analysis included t tests, χ2 tests, and Cox regression analysis. RESULTS: A total of 621 procedures in 517 patients met the inclusion criteria. Of the 621 procedures, 36 (5.8%) were classified as procedures in patients with occult cancer. The patients with occult cancer had had higher occlusion rates at 3 months (27.8% vs 8.0%; P < .001), 6 months (30.5% vs 15.1%; P < .01), and 1 year (44.4% vs 19.8%; P < .001). In Cox regression analysis for bypass thrombosis at 1 year, the only significant predictors were occult cancer (hazard ratio [HR], 2.03; P = .01), below-the-knee distal target (HR, 1.88; P < .01), and a compromised conduit (HR, 2.14; P < .001). CONCLUSIONS: We found an increase in bypass graft thrombosis rates in patients who had undergone femoropopliteal bypass who had had occult cancer. Thrombosis of the graft within 1 year postoperatively might be a sign of occult cancer.

Comparative Analysis of Outcomes in Patients Undergoing Femoral Endarterectomy plus Endovascular (Hybrid) or Bypass for Femoropopliteal Occlusive Disease.

INTRODUCTION: The gold-standard for management of combined common femoral artery (CFA) and superficial femoral artery (SFA) atherosclerotic occlusive disease has traditionally been open femoral endarterectomy and femoral-popliteal bypass. Hybrid approaches involving an open and endovascular component are increasingly common. The aim of this study was to compare perioperative outcomes in patients who underwent an open versus hybrid revascularization. METHODS: NSQIP data, years 2012-2017, were queried for patients who underwent nonemergent CFA endarterectomy with either SFA transluminal intervention or bypass. The primary outcome of interest was a composite of cardiovascular, pulmonary, and renal complications (systemic) and mortality. Two propensity-weight adjusted analyses were performed: 1) comparing hybrid and prosthetic bypass 2) comparing hybrid and vein bypass. RESULTS: There were 4,478 patients included (1,537 hybrid, 1,408 prosthetic, 1,533 vein); 64.8% were men, and the mean age was 67.8 ± 9.7 years; 29.9% had claudication, 38.8% had tissue loss, and 31.3 were unspecified. In the propensity-weighted analysis comparing hybrid to prosthetic bypass, there was no difference in systemic complications (OR = 1.29 for prosthetic vs. hybrid; 95% CI: 0.95-1.76; P = 0.107) or mortality (OR = 1.54; 95% CI: 0.71-3.33; P = 0.275). Prosthetic bypass was associated with more deep surgical-site infections (OR = 2.02; 95% CI: 1.19-3.45; P = 0.010), postoperative sepsis (OR = 2.07; 95% CI: 1.13-3.76; P = 0.018), unplanned 30-day readmission (OR = 1.28; 95% CI: 1.04-1.58; P = 0.021), and the composite of any complication (OR = 1.38; 95% CI: 1.18-1.61; P < 0.001). In the propensity-weighted analysis comparing hybrid to vein bypass, there was no difference in systemic complications (OR = 1.10 for vein vs. hybrid; 95% CI: 0.81-1.49; P = 0.552) or mortality (OR = 0.91; 95% CI: 0.42-2.00; P = 0.819). Vein bypass was associated with more superficial surgical-site infections (OR = 1.45; 95% CI: 1.04-2.02; P = 0.028), and the composite of any complication (OR = 1.32; 95% CI: 1.13-1.54; P = 0.001). Overall mortality was significantly higher patients with systemic complications (13.9% vs 0.1%; P < 0.001). Systemic complications were less common in patients with claudication undergoing hybrid revascularization than vein or prosthetic bypass. CONCLUSIONS: Claudicants undergoing bypass experienced more systemic complications than those undergoing hybrid procedures, but there appears to be no increased risk of systemic complications or mortality with open reconstruction when compared to hybrid procedures for other indications. Other complications, such as infection, postoperative transfusion, and readmission, were more common in the bypass groups.

Trends and Determinants of Readmissions to Another Facility After Endovascular Aortic Repair.

BACKGROUND: Endovascular aneurysm repair (EVAR) has become the procedure of choice for abdominal aortic aneurysms (AAAs). It has been previously reported that significant percentage of patients were being readmitted to another hospital after complications after EVAR. We aimed to evaluate trends and clinical predictors of readmission to another (secondary) hospital after index EVAR. METHODS: The Nationwide Readmissions Database (NRD) was queried for all 30-day readmissions after an index EVAR procedure from 2012 to 2014. Readmission diagnosis, patient demographics, and hospital characteristics were collected regarding those patients who were admitted to another care facility after EVAR. Univariate analysis and multivariable logistic regression model was used to identify predictors for readmission to a different hospital. RESULTS: Between 2012 and 2014, 3,215 patients were readmitted to another hospital within 30 days of their index EVAR constituting 22.8% of a total 14,073 readmissions during that time period. Comorbidities of patients examined were similar between those patients readmitted to the primary hospital versus the secondary hospital except for the incidence of hypothyroidism (P < 0.001). Higher proportion of patients admitted to a different hospital had Medicare and Medicaid insurance (P < 0.047). In addition, higher proportion of patients readmitted to secondary hospitals had EVAR performed at smaller (<100 beds) hospitals (P = 0.002). Univariate analysis demonstrated that patients readmitted to another hospital were slightly older and had higher index length of stay and higher index hospital cost after EVAR (P < 0.001). In a multivariate model, index EVAR at a small hospital (odds ratio [OR]: 1.7) and the diagnosis of hypothyroidism (OR: 1.54) were independent determinants of readmission to another care facility. CONCLUSIONS: Significant proportion of patients is being readmitted elsewhere after elective EVAR adding complexity to the determination of appropriate healthcare resource allocation. In our study, index EVAR at a small hospital (<100 beds) and pre-existing medical comorbidity of hypothyroidism were significant predictors for unanticipated readmission to a different hospital.

Higher Inpatient Mortality for Women after Intervention for Lifestyle Limiting Claudication.

BACKGROUND: Sex-related differences in outcomes have been identified in patients with peripheral artery disease (PAD). We hypothesized that women with PAD would have equivalent inpatient mortality with men after vascular intervention. METHODS: Patients with a primary diagnosis of critical limb ischemia (CLI) or lifestyle-limiting claudication (LLC) receiving endovascular (EV) or open surgical repair from 2003-2012 were identified from the Nationwide Inpatient Sample. Demographics, comorbidities, and inpatient mortality were analyzed by chi-squared tests of independence and independent-samples t-tests. Logistic regression analysis was performed to identify predictors of inpatient mortality. SPSS 24 software was used with P < 0.05 considered statistically significant. RESULTS: We identified 139,435 (59,432 women and 80,003 men) individuals meeting the aforementioned criteria. Women were older than men (71.5 years vs. 68.2, P < 0.001). There were no differences in racial distribution but women had lower rates of diabetes (38.6% vs. 39.7%, P < 0.001), chronic obstructive pulmonary disease (17.9% vs. 19.5%, P < 0.001), and coronary artery disease (38.6% vs. 47.4%, P < 0.001), while having a higher rate of hypertension (60.0% vs. 56.1%, P < 0.001). There was no sex-related difference in the rate of chronic renal failure. Women had higher inpatient mortality than men after vascular intervention (1.3% vs. 1.1%, P < 0.001). When stratified by surgical technique, women also had higher inpatient mortality after EV repair (1.0% vs. 0.8%, P < 0.05) and open repair (1.9% vs 1.3%, P < 0.001). When separated by admitting diagnosis, women with CLI had higher inpatient mortality than men after open surgery (2.3% vs. 1.9%, P < 0.05) but not after EV intervention. Women with LLC had higher inpatient mortality after both open (0.6% vs. 0.3%, P < 0.05) and EV surgery (0.3% vs. 0.1%, P < 0.05). Regression analysis revealed female sex as an independent predictor of inpatient mortality in patients with LLC (OR, 1.74; 95% CI 1.30-2.32, P < 0.001) but not CLI. CONCLUSIONS: Women had higher inpatient mortality than men after vascular intervention for PAD. Women were also older and more likely to have EV intervention than men. Subgroup analysis suggests that these sex-related differences in inpatient mortality are more pronounced in patients with LLC than with CLI. Furthermore, regression analysis shows that sex is a significant predictor for patients diagnosed with LLC but not with CLI. Treatment guidelines should include consideration of sex in their indications for revascularization, particularly for patients diagnosed with LLC.

Incisional Negative Pressure Wound Therapy Augments Perfusion and Improves Wound Healing in a Swine Model Pilot Study.

BACKGROUND: A commonly used treatment for open wounds, negative pressure wound therapy (NPWT) has recently been used to optimize wound healing in the setting of surgically closed wounds; however, the specific mechanisms of action by which NPWT may benefit patients after surgery remain unknown. Using a swine wound healing model, the current study investigates angiogenesis as a candidate mechanism. METHODS: Multiple excisional wounds were created on the dorsa of 10 male Yorkshire pigs and closed by primary suture. The closed wounds underwent treatment with either NPWT dressing or control dressings in the absence of negative pressure. Dressings were maintained for 8 days followed by euthanasia of the animal. Scar evaluation of the wounds by photographic analysis was performed, and wounds were analyzed for angiogenesis markers by enzyme-linked immunosorbent assay and immunohistochemistry. RESULTS: Scar evaluation scores were observed to be significantly higher for the NPWT-treated sites compared with the control sites (P < 0.05). The enzyme-linked immunosorbent assay results demonstrated increases for vascular endothelial growth factor (VEGF) staining at the incision site treated with NPWT compared with other treatment groups (P < 0.05). In addition, an approximately 3-fold elevation in VEGF expression was observed at the NPWT-treated sites (2.8% vs. 1%, respectively; P < 0.0001).). However, there was no significant difference in immunohistochemistry staining. CONCLUSIONS: The use of NPWT improves the appearance of wounds and appears to increase VEGF expression after 8 days in the setting of a closed excisional wound model, suggesting that improved angiogenesis is one mechanism by which NPWT optimizes wound healing when applied to closed surgical wound sites.

Endovascular interventions decrease length of hospitalization and are cost-effective in acute mesenteric ischemia.

OBJECTIVE: Acute mesenteric ischemia (AMI) continues to be one of the most devastating diagnoses requiring emergent vascular intervention. There is a national trend toward increased use of endovascular procedures, with improved survival for the treatment of these patients. Our aim was to evaluate whether this trend has changed the treatment of AMI and the subsequent impact on length of hospitalization and hospitalization costs. METHODS: We identified all patients admitted for AMI from the National Inpatient Sample from 2004 to 2014 who received open surgical revascularization (OPEN) or an endovascular intervention (ENDO). Primary end points included length of hospital stay and cost of hospitalization. Our secondary end points included acute kidney injury (AKI), in-hospital mortality, and routine discharge. RESULTS: Among 10,381 discharges identified in the data set, 3833 (37%; 97.5% confidence interval [CI], 35%-39%) were male patients with a mean age of 69 years (range, 18-98 years); 4543 (44%; 97.5% CI, 41%-47%) patients were treated ENDO, and 5839 (56%; 97.5% CI, 53%-59%) patients were treated OPEN. Although a higher proportion of patients in the ENDO group (28%; 97.5% CI, 24%-31%) vs the OPEN group (14%; 97.5% CI, 11%-16%) had a moderate to severe Charlson Comorbidity Index (P < .0001), ENDO was associated with a lower mortality rate (12.3% [97.5% CI, 9.8%-14.8%] vs 33.1% [97.5% CI, 29.9%-36.2%]; P < .0001) and a lower mean hospitalization cost ($41,615 [97.5% CI, $38,663-$44,567] vs $60,286 [97.5% CI, $56,736-$63,836]; P < .0001). After propensity-adjusted logistic regression analysis, OPEN retained a significant association with higher mortality than ENDO (odds ratio, 3.0; 97.5% CI, 2.2-4.1) and with higher costs (mean, $9196; 97.5% CI, $3797-$14,595). Patients in the OPEN group had higher risk for AKI (P < .0001) and discharge to a skilled nursing facility (P < .0001) rather than home. CONCLUSIONS: Although the rate of ENDO continues to rise nationally, it still has not surpassed OPEN revascularization in the face of AMI. Patients treated endovascularly demonstrated one-third the rate of in-hospital mortality (odds ratio, 3.0; 97.5% CI, 2.2-4.1), an increased hazard ratio for discharge alive (hazard ratio, 2.27; 97.5% CI, 2.00-2.58), and a cost saving of $9196 (97.5% CI, $3797-$14,595) per hospitalization. Furthermore, they were less likely to develop AKI and to be discharged home after hospitalization.

Improved mortality in treatment of patients with endovascular interventions for chronic mesenteric ischemia.

OBJECTIVE: Chronic mesenteric ischemia (CMI) continues to be a devastating diagnosis. There is a national trend toward increased use of endovascular procedures with improved survival for the treatment of these patients. Our aim was to evaluate whether this trend has changed CMI patients' length of hospitalization and health care cost. METHODS: We identified all patients admitted for CMI from the National Inpatient Sample (NIS) from 2000 to 2014. Our primary end points included length of hospital stay (LOS) and cost of hospitalization (COH). Our secondary end points included mortality assessment of the CMI hospitalization. RESULTS: There were 15,475 patients admitted for CMI. The mean age of patients was 71 years, and 4022 (26.0%) were male. There were 10,920 (70.6%) patients treated endovascularly (ENDO) and 4555 (29.4%) patients treated in an open fashion (OPEN). Although a higher proportion of patients in the ENDO (43.3%) group vs OPEN (33.1%) had a Charlson Comorbidity Index score of ≥2 (P < .0001), they had a lower mortality rate (2.4% vs 8.7%; P < .0001), lower mean LOS (6.3 vs 14.0 days; P < .0001), and lower COH ($21,686 vs $42,974; P < .0001). After adjusting for clinical and hospital factors, OPEN continued to demonstrate higher mortality than ENDO (odds ratio, 7.2; 95% confidence interval, 4.9-10.6; P < .0001), longer LOS (mean, +9.7 days; P < .0001), and higher COH (mean, +$25,834; P < .0001). CONCLUSIONS: The rate of ENDO continues to rise nationally in the treatment of CMI patients. After adjusting for clinical and hospital factors, patients in the ENDO group tend to have lower in-hospital mortality of 2.4% and lower LOS by 10 days, and they incur a cost saving of >$25,000 compared with patients in the OPEN group. ENDO should be considered first line of therapy for patients with CMI.

Increased mortality in octogenarians treated for lifestyle limiting claudication.

OBJECTIVE: Treatment for lifestyle limiting claudication (LLC) that is due to infra-inguinal peripheral artery disease relies on either bypass, angioplasty, and/or stenting. Given the enthusiasm and shift toward more endovascular therapy for treatment of LLC, we sought to analyze whether octogenarians benefit from infra-inguinal interventions in the same manner as their younger counterparts. METHODS: We identified all patients admitted for elective treatment of LLC from the Nationwide Inpatient Sample from 2003 to 2012, who received open surgical or endovascular intervention for infra-inguinal peripheral arterial disease. These patients were divided into two groups including those between the ages 60-80 years (younger cohort) and those older than 80 years (octogenarians). Primary end-points included morbidity and mortality and the secondary end-points were length of hospital stay (LOS) and disposition after dismissal. RESULTS: Among 59,323 discharges identified in the dataset, 34,658 (58%) were males. There were 50,323 (85%) patients in the younger cohort and 9,000 (15%) octogenarians. The mean age was 69.9 ± 5.7 years and 84.2 ± 3.0 years for the younger cohort and octogenarians, respectively. The mean Charlson comorbidity index (CCI) was higher in our younger cohort (2.1 ± 1.1, P < 0.001). Octogenarians mainly treated with open surgery prior to 2004 are now treated endovascularly and this trend has remained stable. The younger cohort's treatment modality has fluctuated through the study period and most recently is treated mainly with open surgery. The rate of acute kidney injury, exacerbation of congestive heart failure and mortality was higher in octogenarians (P < 0.001). The rate of infectious wound complications was higher in the younger cohort (P < 0.05). Octogenarians have longer LOS and are dismissed in higher percentage to a skilled nursing facility (P < 0.001). On binary logistic regression analysis, age over 80 years, female sex, higher CCI and having an open as opposed to an endovascular procedure are independent predictors of in-hospital mortality. CONCLUSIONS: Although endovascular techniques seem to dominate the care for octogenarians with LLC, the overall morbidity and mortality rates are significantly higher in this patient population. Other options such as medical management and/or supervised exercise therapy should be explored in this patient group.

Regulation of Yes-Associated Protein by Laminar Flow.

BACKGROUND: The cells lining the endothelium of blood vessels are recognized as playing critical roles in vascular health and disease. The mechanisms that regulate endothelial cells (ECs) proliferation and release of mediators remain poorly understood but represent a potential source of disease modulation. Actin-cytoskeleton remodeling and cell shape have been suggested as key regulators of phosphorylation of yes-associated protein (YAP) which controls cellular growth and proliferation. Because different types of flow have been shown to affect cell shape and cytoskeleton differently, we hypothesized that the level of phosphorylated yes-associated protein (pYAP; serine 127) decreases in EC exposed to pulsatile uniform flow or steady laminar flow, whereas exposure to pulsatile disturbed flow causes an increase or no change. METHODS: Human umbilical vein endothelial cells (HUVECs) were exposed to pulsatile uniform flow, pulsatile disturbed flow, or steady laminar flow and analyzed by immunoblotting. RESULTS: Exposure of HUVECs to steady laminar flow caused a significant decrease in the levels of pYAP (69.7 + 2.6%, P < 0.05), whereas total YAP levels remained nearly unchanged. Conversely, exposure to either pulsatile uniform or disturbed flow caused a significant decrease in the levels of both pYAP (63.2 + 10.9% and 69.8 + 11.9%, respectively; P < 0.05) and total YAP (57.1 + 17.8% and 58.4 + 16.3%, respectively; P < 0.05). Addition of MG132, a ubiquitin-proteasome system inhibitor, failed to significantly inhibit the decrease in the levels of total YAP in HUVECs exposed to either pulsatile uniform or disturbed flow. CONCLUSIONS: Flow causes a decrease in pYAP. The observed decrease in total YAP levels with pulsatile flow is due to degradation via a proteasome-independent mechanism. This may be a potential target for intervention for disease states such as atherosclerosis and intimal hyperplasia.

Acute Limb Ischemia in an 8-Year-Old Patient: A Case Report.

We report the case of an 8-year-old patient with a history of nephrotic syndrome, who presented to the emergency department with right foot pain. The patient's mother described intermittent pain that woke her son from sleep and was accompanied by the foot turning purple and becoming cold to touch. Physical examination revealed capillary refill of over 10 seconds in the right and less than 2 seconds in the left foot. Ankle-brachial indices (ABIs) were 0.0 on the right and 0.96 on the left. The patient was admitted and started on therapeutic intravenous heparin. After consultation with his parents, right lower extremity angiography and thrombolysis was performed over 2 days. He subsequently underwent fasciotomy and amputation of the tip of all 5 toes. Eighteen months later, there is no leg length discrepancy, he is walking with foot inserts and has normal ABIs bilaterally.