Analysis of Oklahoma amputation trends and identification of risk factors to target areas for limb preservation interventions.

OBJECTIVE: Annual trends of lower extremity amputation due to end-stage chronic disease are on the rise in the United States. These amputations are leading to massive expenses for patients and the medical system. In Oklahoma, we have a high-risk population because access to care is low, the number of uninsured is high, cardiovascular health is poor, and our overall health care performance is ranked 50th in the country. But we know little about Oklahomans and their risk of limb loss. It is, therefore, imperative to look closely at this population to discover contemporary rates, trends, and state-specific risk factors for amputation due to diabetes and/or peripheral arterial disease (PAD). We hypothesize that state-specific groups will be identified as having the highest risk for limb loss and that contemporary trends in amputations are rising. To create implementable solutions to limb preservation, a baseline must be set. METHODS: We conducted a 12-consecutive-year observational study using Oklahoma's hospital discharge data. Discharges among patients 20 years or older with a primary or secondary diagnosis of diabetes and/or PAD were included. Diagnoses and amputation procedures were identified using International Classification of Disease-9 and -10 codes. Amputation rates were calculated per 1000 discharges. Trends in amputation rates were measured by annual percentage changes (APC). Prevalence ratios evaluated the differences in amputation rates across demographic groups. RESULTS: Over 5,000,000 discharges were identified from 2008 to 2019. Twenty-four percent had a diagnosis of diabetes and/or PAD. The overall amputation rate was 12 per 1000 discharges for those with diabetes and/or PAD. Diabetes and/or PAD-related amputation rates increased from 8.1 to 16.2 (APC, 6.0; 95% confidence interval [CI], 4.7-7.3). Most amputations were minor (59.5%), and although minor, increased at a faster rate compared with major amputations (minor amputation APC, 8.1; 95% CI, 6.7-9.6 vs major amputation APC, 3.1; 95% CI, 1.5-4.7); major amputations were notable in that they were significantly increasing. Amputation rates were the highest among males (16.7), American Indians (19.2), uninsured (21.2), non-married patients (12.7), and patients between 45 and 49 years of age (18.8), and calculated prevalence ratios for each were significant (P = .001) when compared within their respective category. CONCLUSIONS: Amputation rates in Oklahoma have nearly doubled in 12 years, with both major and minor amputations significantly increasing. This study describes a worsening trend, underscoring that amputations due to chronic disease is an urgent statewide health care problem. We also present imperative examples of amputation health care disparities. By defining these state-specific areas and populations at risk, we have identified areas to pursue and improve care. These distinctive risk factors will help to frame a statewide limb preservation intervention.

Creating hemodialysis autogenous access in children and adolescents.

OBJECTIVE: End-stage renal disease (ESRD) in childhood and adolescence is rare, with relatively few published reports of pediatric ESRD vascular access. This study analyzes a 10-year experience creating arteriovenous fistulas (AVFs) in children and adolescents. Our goal is to review our strategy for creating functional autogenous vascular access in younger patients and report our results. METHODS: We retrospectively reviewed data and outcomes for consecutive vascular access patients aged ≤19 years during a 10-year period. Each patient had preoperative vascular ultrasound mapping by the operating surgeon in addition to physical examination. A distal forearm radiocephalic AVF was the first access choice when feasible, and a proximal radial artery inflow AVF was the next option. Demographic data, inflow artery, venous outflow target, and required transposition vs direct AVFs were variables included in the analysis. Primary and cumulative patency were calculated by Kaplan-Meier analysis. RESULTS: Thirty-seven AVFs were created in 35 patients. No grafts were used. Ages were 6 to 19 years (mean, 15 years), and 20 were male. Causes of ESRD included glomerular disease (n = 18) and urinary obstruction or reflux (n = 7), among others. Three had previous AVFs, and 10 were obese. The proximal radial artery supplied AVF inflow in 25 patients and the brachial artery in only seven. Eleven individuals required a transposition and one a vein translocation to the contralateral arm. No patients developed hand ischemia, although two later required banding procedures for high flow. Eleven patients had successful transplants. A single patient died, unrelated to the vascular access. Five AVFs failed. Of these, two had new successful AVFs created, two regained renal function, one was transplanted, and one declined other procedures. Primary and cumulative patency rates were 75% and 85% at 12 months, 70% and 85% at 24 months, and 51% and 85% at 36 months, respectively. Median follow-up was 16 months. CONCLUSIONS: Creating an AVF for hemodialysis is a successful vascular access strategy for pediatric and adolescent patients. Proximal radial artery AVFs provided safe and functional access when a distal AVF was not feasible. Cumulative AVF patency was 85% at 36 months.

Short-Term Concerns Primarily Determine Patient Preference for Abdominal Aortic Aneurysm Repair.

INTRODUCTION: Abdominal aortic aneurysm (AAA) repair may be performed through open or endovascular approaches, but the factors influencing a patient's repair-type preference are not well characterized. Here we performed a qualitative analysis to better understand factors influencing patient preference within the Preference for Open Versus Endovascular Repair of AAA Trial. METHODS: Open-ended responses regarding primary (n = 21) and secondary (n = 47) factors influencing patient preference underwent qualitative analysis using the constant comparative method with iterative reviews. Codes were used to generate themes and themes grouped into categories, with each step conducted via consensus agreement between three researchers. Relative prevalence of themes were compared to ascertain trends in patient preference. RESULTS: Patient responses regarding both primary and secondary factors fell into four categories: Short-term concerns, long-term concerns, advice & experience, and other. Patients most frequently described short-term concerns (23) as their primary influence, with themes including post-op complications, hospitalization & recovery, and intraoperative concerns. Long-term concerns were more prevalent (20) as secondary factors, which included themes such as survival, and chronic management. The average age of patients voicing only long-term concerns as a primary factor was 11 years younger than those listing only short-term concerns. CONCLUSION: Short-term concerns relating to the procedure and recovery are more often the primary factor influencing patient preference, while long term concerns play a more secondary role. Long-term concerns are more often a primary factor in younger patients. Vascular surgeons should consider this information in shared decision making to reach an optimal outcome.

Autogenous Vascular Access in American Indians.

BACKGROUND: American Indians (AI) or Alaska Natives, or in combination with another race, comprised 6.8 million individuals in 2010 and the population is expected to exceed 10 million in the current census. Diabetes is more common in AIs than in other races in the United States and is responsible for 69% of new onset end stage renal disease in AI patients. The incidence of obesity is also higher among AIs. As both diabetes and obesity make creating a successful autogenous vascular access more challenging, we reviewed our experience creating arteriovenous fistulas in AI patients. METHODS: Our vascular access database was reviewed for consecutive new AI patients undergoing creation of a hemodialysis vascular access during a 10-year period. Each patient underwent ultrasound vessel mapping by the operating surgeon in addition to history and physical examination. The goal for initial cannulation was 4-6 weeks after access creation. Minimal AVF flow volume for cannulation was 500 mL/min with an outflow vein diameter of 6 mm. RESULTS: 235 consecutive new AI patients were identified. All patients had an autogenous access constructed. The median age was 56 years (range, 15-89 years). Diabetes was present in 85% and 42% were female. Obesity was noted in 27% of the patients and 37% had previous vascular access operations. Primary patency at 12 and 24 months was 62% and 46%, respectively. Cumulative patency at 12 and 24 months was 96% and 94%, respectively. Female gender and previous access operations were associated with lower primary (P = 0.002 and 0.02, respectively) and cumulative patency (P = 0.01 and 0.04, respectively). Obesity was associated with lower cumulative access patency (P = 0.02). Overall, 74% of the access operations used the radial or ulnar artery for AVF inflow. Distal radial artery inflow AVFs were associated with longer patient survival (P = 0.01) and individuals with proximal radial inflow had longer survival when compared to brachial artery AVFs. Previous access operations were associated with shorter patient survival (P = 0.04). CONCLUSIONS: Safe and functional arteriovenous fistulas can be created for American Indians despite a higher prevalence of vascular access risk factors such as diabetes and obesity.

Reading light: leaf spectra capture fine-scale diversity of closely related, hybridizing arctic shrubs.

Leaf reflectance spectroscopy is emerging as an effective tool for assessing plant diversity and function. However, the ability of leaf spectra to detect fine-scale plant evolutionary diversity in complicated biological scenarios is not well understood. We test if reflectance spectra (400-2400 nm) can distinguish species and detect fine-scale population structure and phylogenetic divergence - estimated from genomic data - in two co-occurring, hybridizing, ecotypically differentiated species of Dryas. We also analyze the correlation among taxonomically diagnostic leaf traits to understand the challenges hybrids pose to classification models based on leaf spectra. Classification models based on leaf spectra identified two species of Dryas with 99.7% overall accuracy and genetic populations with 98.9% overall accuracy. All regions of the spectrum carried significant phylogenetic signal. Hybrids were classified with an average overall accuracy of 80%, and our morphological analysis revealed weak trait correlations within hybrids compared to parent species. Reflectance spectra captured genetic variation and accurately distinguished fine-scale population structure and hybrids of morphologically similar, closely related species growing in their home environment. Our findings suggest that fine-scale evolutionary diversity is captured by reflectance spectra and should be considered as spectrally-based biodiversity assessments become more prevalent.

Heterogeneous and dynamic lumen remodeling of the entire infrainguinal vein bypass grafts in patients.

OBJECTIVE: To examine the regional variation and temporal change in lumen size along the entire autogenous vein bypass graft used for treating arterial occlusive disease in lower extremity and to explore the factors associated with graft expansive or constrictive remodeling. METHODS: Patients were prospectively scanned using contrast-enhanced computed tomography at 1 week and 1, 6, and 12 months postoperatively to obtain lumen cross-sectional areas at 1-mm intervals along the entire grafts. Graft lumen remodeling characteristics and the associated demographic and clinical factors were examined. RESULTS: Fifty-six patients with at least two consecutive computed tomography scans were analyzed. Patients with a composite or longer graft, or with diabetes, had a larger lumen cross-sectional area variation along the graft. The mean lumen cross-sectional areas of all the grafts demonstrated no significant changes through 12 months. However, individually, graft remodeling was time dependent and there was a more dramatic change in lumen cross-sectional area within the first postoperative month. At 12 months, a near equal distribution between expansive and constrictive grafts existed. A negative relation between the initial lumen diameters and the subsequent lumen diameter changes was observed. Eleven grafts failed within 12 months; failed and patent grafts had similar mean lumen cross-sectional areas at all four time points, but failed grafts had a larger maximal local cross-sectional area reduction from 1 week to 1 month (58.0 ± 6.7% vs 38.1 ± 3.1%, mean ± standard error of the mean, failed vs patent, P = .004). Black patients had a smaller mean lumen cross-sectional area than white patients at all four time points and also had a higher early percent mean area reduction (-20.5 ± 6.3% vs -1.0 ± 3.7%, black vs white, P = .018). Cilostazol use was associated with early expansive graft remodeling. CONCLUSIONS: Vein grafts remodel heterogeneously and dynamically. Remodeling is associated with initial graft lumen size, race, and cilostazol use. It is found that remodeling that produces some critical minimum area or maximal percent reduction during the first postoperative month may predispose to vein graft failure. These findings offer insight into further investigation to examine the underlying mechanisms and opportunities to improve graft remodeling and durability.

Comparison of Outcomes of Percutaneous Arteriovenous Fistulae Creation by Ellipsys and WavelinQ Devices.

PURPOSE: The purpose of this study was to compare the clinical outcomes of Ellipsys with those of WavelinQ-4F percutaneous arteriovenous fistulae (pAVF) devices in a single center by a single operator. MATERIALS AND METHODS: A retrospective review was conducted in 100 patients who underwent pAVFs procedures (65 Ellipsys and 35 WavelinQ patients) and created between December 2017 and December 2019. A total of 69% were male and 37% were diabetic. Median age was 64.1 years (range: 28-86), and median body mass index was 27.2 (range: 15-45.1) kg/m2. A procedure sequence algorithm was followed for selecting all vascular accesses created. RESULTS: Ellipsys outcomes were compared to WavelinQ outcomes. Technical success was 100% versus 97%, respectively, and median procedure times were 14 versus 63 minutes, respectively (P < .001), with 183 (1-487) versus 185 (0-760) days follow-up, respectively. Maturation at 4 weeks was 68.3% versus 54.3%, respectively, and median times to cannulation were 60 (1-164) versus 90 (1-180) days, respectively. Successful pAVF dialysis was established in 31 of 39 patients (79.5%) versus 14 of 24 patients (58%), respectively (P = .071), dialysis patients with access-related adverse events observed in 4 individuals (1 Ellipsys versus 3 WavelinQ). Six patients (5 versus 1) with matured outflow from previous AVFs underwent first-day cannulations. Interventions were performed in 27.7% (33 Ellipsys) and 26.5% (15 WavelinQ) patients, and the number of interventions per patient-years was 0.96 versus 0.46, respectively. pAVF failure was seen in 15.4% versus 37.1% patients, respectively (P = .0137). Secondary patency at 12 months was significantly higher among patients who had an Ellipsys procedure (82%) than among those who underwent the WavelinQ procedure (60%). CONCLUSIONS: pAVFs were created with high technical success and low complications with both devices. Ellipsys pAVFs demonstrated significantly shorter procedure times without a need for radiation exposure and with superior secondary patency.

Frailty Syndrome in Patients with Carotid Disease: Simplifying How We Calculate Frailty.

BACKGROUND: Frailty syndrome is an established predictor of adverse outcomes after carotid surgery. Recently, a modified 5-factor National Surgical Quality Improvement Program frailty index has been used; however, its utility in vascular procedures is unclear. The aim of our study was to compare the 5-factor modified frailty index (mFI-5) with the 11-factor modified frailty index (mFI-11) regarding value and predictive ability for mortality, postoperative infection, and unplanned 30-day readmission. METHODS: The mFI was calculated by dividing the number of factors present for a patient by the number of available factors for which there were no missing data. Spearman rho test was used to assess the correlation between the mFI-5 and mFI-11. Predictive models, using both unadjusted and adjusted logistic regressions, were created for each outcome for carotid endarterectomy using 2005-2012 National Surgical Quality Improvement Program data, the last year all mFI-11 variables existed. RESULTS: A total of 36,000 patients were included with mean age of 74.6 ± 5.9 years, complication rate of 10.7%, mortality rate of 3.1%, and readmission rate of 6.2%. Correlation between mFI-5 and mFI-11 was above 0.9 across all outcomes for patients. mFI-5 had strong predictive ability for mortality, postoperative complications, and 30-day readmission. CONCLUSIONS: The mFI-5 and mFI-11 are equally effective predictors of postoperative outcomes in patients undergoing carotid endarterectomy. mFI-5 is a strong predictor of postoperative complications, mortality, and 30-day readmission.

Novel climates reverse carbon uptake of atmospherically dependent epiphytes: Climatic constraints on the iconic boreal forest lichen Evernia mesomorpha.

PREMISE OF THE STUDY: Changing climates are expected to affect the abundance and distribution of global vegetation, especially plants and lichens with an epiphytic lifestyle and direct exposure to atmospheric variation. The study of epiphytes could improve understanding of biological responses to climatic changes, but only if the conditions that elicit physiological performance changes are clearly defined. METHODS: We evaluated individual growth performance of the epiphytic lichen Evernia mesomorpha, an iconic boreal forest indicator species, in the first year of a decade-long experiment featuring whole-ecosystem warming and drying. Field experimental enclosures were located near the southern edge of the species' range. KEY RESULTS: Mean annual biomass growth of Evernia significantly declined 6 percentage points for every +1°C of experimental warming after accounting for interactions with atmospheric drying. Mean annual biomass growth was 14% in ambient treatments, 2% in unheated control treatments, and -9% to -19% (decreases) in energy-added treatments ranging from +2.25 to +9.00°C above ambient temperatures. Warming-induced biomass losses among persistent individuals were suggestive evidence of an extinction debt that could precede further local mortality events. CONCLUSIONS: Changing patterns of warming and drying would decrease or reverse Evernia growth at its southern range margins, with potential consequences for the maintenance of local and regional populations. Negative carbon balances among persisting individuals could physiologically commit these epiphytes to local extinction. Our findings illuminate the processes underlying local extinctions of epiphytes and suggest broader consequences for range shrinkage if dispersal and recruitment rates cannot keep pace.

Comparison of the integrated vascular surgery resident operative experience and the traditional vascular surgery fellowship.

OBJECTIVE: After almost 10 years since its approval, residents in integrated vascular surgery training programs now outnumber traditional vascular fellows. We examined the Accreditation Council for Graduate Medical Education (ACGME) case log data to assess whether there is a difference in operative experience between the graduating integrated residents and vascular fellows. METHODS: We analyzed the total clinical experience of vascular surgery trainees during the academic years between 2012 and 2014 for the 30 graduated integrated vascular surgery residents (VSRs) and the 243 graduated vascular surgery fellows (VSFs). Data were compared on the basis of reported categories defined by the ACGME operation reporting system. VSR case totals were calculated by combining "surgeon chief," "surgeon junior," and "secondary procedures" categories. VSF "surgeon fellow" and "secondary procedures" case totals were combined with all vascular cases done in general surgery residency (using averages of general surgery resident ACGME case log data from the same years) to reflect their total vascular experience. RESULTS: The average total vascular experience reported by VSRs was 1446.0 compared with 1421.8 for VSFs (P = .2086). VSRs performed 694.7 major vascular procedures on average compared with 616.3 major cases for VSFs (P = .0106). Highlighted comparisons include the following: open aortic aneurysm cases, VSRs 20.6 and VSFs 22.2 (P = .320); endovascular aortic aneurysm cases, VSRs 80.0 and VSFs 80.6 (P = .945); cerebrovascular cases, VSRs 78.8 and VSFs 85.0 (P = .1132); and peripheral obstructive cases, VSRs 343.6 and VSFs 293.4 (P = .0032). CONCLUSIONS: Integrated VSRs and traditional VSFs graduate with comparable overall vascular surgery clinical experience. VSRs reported, on average, a significantly higher number of major vascular procedures during their tenure as trainees as well as a significantly increased number of cases in six of the other ACGME categories.

Open abdominal surgical training differences experienced by integrated vascular and general surgery residents.

BACKGROUND: As the integrated vascular residency program reaches almost a decade of maturity, a common area of concern among trainees is the adequacy of open abdominal surgical training. It is our belief that although their overall exposure to open abdominal procedures has decreased, integrated vascular residents have an adequate and focused exposure to open aortic surgery during training. METHODS: National operative case log data supplied by the Accreditation Council for Graduate Medical Education were compiled for both graduating integrated vascular surgery residents (IVSRs) and graduating categorical general surgery residents (GSRs) for the years 2012 to 2014. Mean total and open abdominal case numbers were compared between the IVSRs and GSRs, with more in-depth exploration into open abdominal procedures by organ system. RESULTS: Overall, the mean total 5-year case volume of IVSRs was 1168 compared with 980 for GSRs during the same time frame (P < .0001). IVSRs reported nearly double the number of surgeon-chief cases compared with GSRs (452 vs 239; P < .0001). GSRs reported more than double the number of open abdominal procedures compared with IVSRs (205 vs 83; P < .0001). Sixty-five percent of the open abdominal experience for IVSRs was focused on procedures involving the aorta and its branches, with an average of 54 open aortic cases recorded throughout their training. The largest single contributor to open surgical experience for a GSR was alimentary tract surgery, representing 57% of all open abdominal cases. GSRs completed an average of 116 open alimentary tract surgeries during their training. Open abdominal surgery represented an average of 7.1% of the total vascular case volume for the vascular residents, whereas open abdominal surgery represented 21% of a GSR's total surgical experience. CONCLUSIONS: IVSRs reported almost double the number of total cases during their training, with double chief-level cases. Sixty-five percent of open abdominal surgeries performed by IVSRs involved the aorta or its renovisceral branches. Whereas open abdominal surgery represented 7.1% of an IVSR's surgical training, GSRs had a far broader scope of open abdominal procedures, completing nearly double those of IVSRs. The differences in open abdominal procedures pertain to the differing diseases treated by GSRs and IVSRs.

Endovascular Management of Proximal Fixation Loss Using Parallel Stent Grafting Techniques to Preserve Visceral Flow.

BACKGROUND: Proximal fixation loss following endovascular aortic aneurysm repair (EVAR) creates a clinical dilemma. Typically, endovascular salvage requires adequate aortic neck below the renal arteries, in cases with no infrarenal neck proximal extension into the paravisceral aorta using parallel grafts provides an alternative to open graft explant. We present our experience at a tertiary care center with endovascular management of proximal fixation loss following EVAR using parallel stent grafting techniques to preserve renal and visceral branches. MATERIALS AND METHODS: We conducted a retrospective review of our type I endoleak database. Of 135 patients, 19 patients were identified that required Ch-EVAR as a salvage procedure for loss of proximal fixation or seal after a previous EVAR. Data from all procedures, as well as the entire hospital course, and documented follow-up were captured and analyzed. RESULTS: The average age of the cohort was 83 (78-88) years. The average time from original EVAR to secondary treatment was 6.05 years. The most common primary endograft treated was the AneuRx stent graft at 37% (n = 7). Ninety-five percent of patients were treated for an expanding aneurysm sac with 21% of patients being symptomatic at the time of treatment. Open femoral access was used more commonly than a percutaneous approach (n = 14 vs. 5). Adjunctive proximal arterial access was required in 58% of cases; open axillary exposure (n = 4), percutaneous brachial (n = 4), and open brachial (n = 3) access. Eighteen patients received proximal cuffs in addition to parallel stent grafts, whereas 1 patient required an entire endograft relining in addition to the parallel visceral stents. Twenty-nine total parallel stent grafts were placed, most commonly in a single renal artery (n = 27). Primary technical success was achieved in 100% of cases with exclusion of all type IA endoleaks. Reintervention was required for 1 patient for a new type III endoleak. There was an average follow-up time of 520.5 days with 100% snorkel patency. CONCLUSIONS: Although technically challenging, endovascular salvage of proximal fixation failure after EVAR is possible with extension to the paravisceral aorta using parallel graft techniques. Parallel chimney stent treatment for proximal fixation failure following EVAR can be performed with high technical success, low need for reintervention, and excellent midterm patency rates. Given these findings, chimney stent treatment should be considered the primary mode of therapy for those patients with limited life span and extensive medical comorbidities.

Thrombomodulin Induces a Quiescent Phenotype and Inhibits Migration in Vascular Smooth Muscle Cells In Vitro.

BACKGROUND: Loss of critical endothelial cell function and subsequent vascular smooth muscle cell (VSMC) migration is central to the pathology of injury-induced neointimal hyperplasia and recurrent stenosis. Thrombomodulin (TM), well known for its function as an endothelial surface anticoagulant, may have an unknown direct effect on VSMC physiology that would be lost after injury. Here, we examined a novel effect of TM on VSMC by testing the hypothesis that direct application of TM induces favorable changes to the morphology of VSMC and inhibits their migration. METHODS: Primary human VSMC were harvested using the explant technique and used in early passage (1-4) for all experiments. Laser-scanning confocal fluorescent imaging was performed to assess the effect of soluble TM on VSMC morphology. In vitro, migration of VSMC was measured using: (1) a 4-hr modified Boyden chemotaxis assay and (2) a 24-hr electric cell-substrate impedance sensing injury migration assay. Migration experiments were conducted with VSMC exposed to increasing doses of soluble recombinant TM. Recombinant thrombin served as a positive control and serum-free media as a negative control for all experimentation. Data were analyzed using a Student's t-test or repeated measures analysis of variance where appropriate (α < 0.05). RESULTS: VSMC exposed to TM clearly demonstrated a quiescent morphology with organized stress fibers consistent with a quiescent, differentiated, contractile phenotype; whereas, thrombin stimulation led to an activated, dedifferentiated, synthetic phenotype. VSMC demonstrated a low, baseline level of migration in unstimulated serum-free conditions. Thrombin significantly stimulated VSMC migration as expected. TM, independent of thrombin, significantly inhibited baseline VSMC migration in a dose-response fashion. The maximal inhibition was observed at (5 µg/mL) with 70% reduction (56 ± 1.7 vs. 18 ± 3.5 cells/5 high-power fields, P = 0.0005). CONCLUSIONS: TM has a direct effect on VSMC resulting in a quiescent, differentiated and contractile phenotype, and inhibition of migration. This effect is independent of the presence of thrombin. These findings provide new knowledge in understanding the pathophysiology of vascular injury and support a strategy focused on restoring key endothelial function to prevent intimal hyperplasia.

Aggressive Costoclavicular Junction Decompression in Patients with Threatened AV Access.

BACKGROUND: A substantial number of patients with threatened arteriovenous (AV) access are found to have stenoses at the costoclavicular junction (CCJ), which frequently are resistant to angioplasty and stenting. We believe that stenoses in this location will not resolve unless bony decompression is performed to relieve the extrinsic compression on the vein. This article describes our short- to medium-term results following such decompression in patients with failing fistulae. METHODS: We reviewed a prospectively maintained database to identify all patients with threatened AV access operated on for stenoses at the CCJ. Pre- and postoperative course along with long-term follow-up were analyzed. RESULTS: Between July 2012 and December 2013, 24 patients with threatened access were operated on for CCJ stenoses at our institution. Fifteen had highly dysfunctional AV fistulae otherwise felt to need ligation, 10 had significant arm and/or head swelling, and 3 required access but had no contralateral options. In 6 patients, the subclavian vein was occluded and 18 stenotic; 5 of these had stents in place through the CCJ. Decompression was performed via claviculectomy in 3 patients, 2 of whom underwent reconstruction (one jugular vein, one prosthetic bypass) and 1 was stented. The other 21 patients underwent first rib resection, 20 via an infraclavicular exposure and 1 via a supraclavicular rib resection. A variety of interventions were performed in the arm, including aneurysm plication, cephalic to deep bypass, one prophylactic distal revascularization interval ligation, and several primary fistulae. 30-Day mortality was minimal: there was one significant hematoma and one hemothorax in a patient who underwent on-table thrombolysis and there were no deaths or cardiac, neurologic, or other significant morbidity. Median length of stay was 2 days. At follow-up up to 20 (median 10) months, 4 patients died of unrelated causes and 1 patient undergoing central reconstruction with prosthetic bypass required excision of this for infection and ligation of his fistula. Two other fistulae failed. One-year assisted primary patency of the fistula was 85%, and of the central bypass, 89%. At last follow-up, the index arm continued to be used for access in 85% of patients, and overall survival was 68%. Virtually all patients experienced dramatic symptom relief. CONCLUSIONS: In this group of high-risk patients whose access was judged otherwise nonsalvageable, excellent symptom relief and long-term fistula and ipsilateral arm use can be achieved with aggressive decompression of the bony CCJ followed by endovascular intervention as needed.

A multicenter, randomized, controlled trial of totally percutaneous access versus open femoral exposure for endovascular aortic aneurysm repair (the PEVAR trial).

OBJECTIVE: The first multicenter randomized controlled trial was designed and conducted to assess the safety and effectiveness of totally percutaneous endovascular aortic aneurysm repair (PEVAR) with use of a 21F endovascular stent graft system and either an 8 F or 10 F suture-mediated closure system (the PEVAR trial, NCT01070069). A noninferiority trial design was chosen to compare percutaneous access with standard open femoral exposure. METHODS: Between 2010 and 2012, 20 U.S. institutions participated in a prospective, Food and Drug Administration-approved randomized trial to evaluate percutaneous femoral artery access and closure by a "preclose" technique in conjunction with endovascular abdominal aortic aneurysm repair. A total of 151 patients were allocated by a 2:1 design to percutaneous access/closure (n = 101) or open femoral exposure (n = 50 [FE]). PEVAR procedures were performed with either the 8 F Perclose ProGlide (n = 50 [PG]) or the 10 F Prostar XL (n = 51 [PS]) closure devices. All endovascular abdominal aortic aneurysm repair procedures were performed with the Endologix 21 F profile (outer diameter) sheath-based system. Patients were screened by computed tomography with three-dimensional reconstruction and independent physician review for anatomic suitability and adequate femoral artery anatomy for percutaneous access. The primary trial end point (treatment success) was defined as procedural technical success and absence of major adverse events and vascular complications at 30 days. An independent access closure substudy evaluated major access-related complications. Clinical utility and procedural outcomes, ankle-brachial index, blood laboratory analyses, and quality of life were also evaluated with continuing follow-up to 6 months. RESULTS: Baseline characteristics were similar among groups. Procedural technical success was 94% (PG), 88% (PS), and 98% (FE). One-month primary treatment success was 88% (PG), 78% (PS), and 78% (FE), demonstrating noninferiority vs FE for PG (P = .004) but not for PS (P = .102). Failure rates in the access closure substudy analyses demonstrated noninferiority of PG (6%; P = .005), but not of PS (12%; P = .100), vs FE (10%). Compared with FE, PG and PS yielded significantly shorter times to hemostasis and procedure completion and favorable trends in blood loss, groin pain, and overall quality of life. Initial noninferiority test results persist to 6 months, and no aneurysm rupture, conversion to open repair, device migration, or stent graft occlusion occurred. CONCLUSIONS: Among trained operators, PEVAR with an adjunctive preclose technique using the ProGlide closure device is safe and effective, with minimal access-related complications, and it is noninferior to standard open femoral exposure. Training, experience, and careful application of the preclose technique are of paramount importance in ensuring successful, sustainable outcomes.

Prescribing patterns of antiplatelet agents are highly variable after lower extremity endovascular procedures.

BACKGROUND: The use of antiplatelet and antithrombotic agents after peripheral vascular interventions is a common clinical practice despite a lack of clear convincing evidence or accepted practice guidelines. The goal of this study was to assess surgeons' prescribing practices after endovascular procedures for lower extremity arterial occlusive disease. METHODS: Attendees at a national vascular meeting were asked to complete a voluntary survey indicating their prescribing practices of antiplatelet/antithrombotic agents for the following procedures: iliac bare-metal stent, iliac covered stent, infrainguinal balloon angioplasty, infrainguinal bare-metal stent, infrainguinal covered stent, infrainguinal atherectomy, and lower extremity cryoplasty. The respondents were given choices of aspirin (ASA) alone, clopidogrel alone, ASA/clopidogrel combined, warfarin alone, or ASA/clopidogrel/warfarin combined. They were also asked to indicate their preferred length of treatment for each medication or combination of medications for each procedure: 1, 3, 6, or 12 months. RESULTS: There were 51 respondents (48 vascular surgeons and 3 vascular fellows) with an average of 11 ± 6.4 years of experience and practicing in a university hospital (48%), community hospital (44%), or combined university/Veterans A hospital (6%) setting. The majority of respondents (98%) prescribe an antiplatelet agent for patients with peripheral arterial disease using 81 mg of ASA preferentially. Most surgeons do not obtain genetic testing (i.e., cytochrome P450, polypeptide 19 [CYP2C19] polymorphism) for antiplatelet effectiveness. The most common antiplatelet/antithrombotic medication of choice after lower extremity endoluminal therapy was a combination of ASA/clopidogrel. However, the duration of medical treatment was variable, with a 1- to 3-month course being the most common. The use of the ASA/clopidogrel combination increased with further distal endovascular treatment and the placement of stents versus angioplasty. In the vast majority of ASA-only responses, ASA was administered for at least 12 months if not recommended for life. Although the majority of surgeons would recommend dual antiplatelet therapy (52-77%), there was no consensus regarding the duration of treatment. CONCLUSIONS: The antiplatelet/antithrombotic prescribing practices of vascular surgeons after lower extremity endovascular procedures are highly variable. Multicenter randomized controlled trials are needed to define optimal treatment efficacy and define the much-needed practice guidelines.

Impact of bariatric surgery on carotid intima-media thickness, flow-mediated dilation, and nitrite-mediated dilation: a systematic review and meta-analysis.

Obesity is considered one of the independent risk factors for atherosclerosis and is strongly correlated with cardiovascular morbidity and mortality. Previous studies showed carotid intima-media thickness (CIMT), flow-mediated dilation (FMD), and nitrite-mediated dilatation (NMD) are reliable non-invasive markers of arterial damage and dysfunction. The aim of this study was to evaluate the effect of bariatric surgery on CIMT, FMD, and NMD markers in patients with obesity. A systematic search was performed in the PubMed, Embase, Scopus, and Web of Science databases until May 2022. All the English-published studies on the effect of bariatric surgery on CIMT, FMD, and NMD were included. A quantitative meta-analysis was performed, as well as subgroup analyses for the type of procedure and duration of follow-up. Meta-analysis of 41 studies with 1639 patients showed CIMT was significantly reduced by .11 mm after bariatric surgery (95% CI, -.14 to -.08; P < .001; mean follow-up = 10.8 mo). The pooled analysis of 23 studies with 1106 patients showed an increase of FMD by 4.57% after bariatric surgery (95% CI, 2.69-6.44; P < .001; mean follow-up = 11.5 mo). The results of a pooled analysis of 12 studies with 346 patients showed a significant increase of NMD by 2.46% after bariatric surgery (95% CI, .99-3.94; P < .001; mean follow-up = 11.4 mo). The random effect meta-regression demonstrated that baseline CIMT and FMD significantly affect the changes in CIMT and FMD. This meta-analysis showed bariatric surgery can improve CIMT, FMD, and NMD markers in patients with obesity. These improvements show the known effect of metabolic surgery in decreasing cardiovascular risk.

Creating reverse flow arteriovenous fistulas with a forearm cannulation target.

BACKGROUND: Establishing a forearm arteriovenous fistula (AVF) offers preferred cannulation sites and preserves proximal access opportunities. When a radiocephalic AVF at the wrist is not feasible and the upper arm cephalic and median cubital veins are inadequate, an AV graft or more complex access procedure is often required. Creating a retrograde flow forearm AVF (RF-AVF) is a valuable alternative where the mid-forearm median antebrachial or cephalic vein is adequate, offering forearm cannulation zones with AVF outflow through deep and superficial collaterals. We report our technique and results. METHODS: We retrospectively reviewed our vascular access data base of consecutive patients during an 11-year study period where a RF-AVF established the only available cannulation target in the forearm. In addition to physical examination, all patients had ultrasound vessel mapping. RESULTS: A forearm access was established with a RF-AVF as the only opportunity for cannulation in 48 patients. Ages were 14-86 years (median = 62 years). Forty-four percent female, 63% diabetic, 13% obese, and 29% had previous access operations. Inflow was proximal radial artery in 47 individuals and one proximal ulnar. Nine AVFs (19%) failed at 2-66 months (median 14 months). One RF-AVF was ligated due to arm edema. Follow-up was 2-111 months (median = 23.5 months). Primary and cumulative patency rates were 62% and 91% at 12 months, and 46% and 85% at 24 months. Five patients were lost to follow-up with functioning RF-AVFs (mean 41 months). Twenty-three patients (48%) died during F/U of causes unrelated to access procedures (mean 25 months). CONCLUSIONS: Establishing a reverse flow forearm AVF offers a successful autogenous access option in the forearm for selected patients with an inadequate distal radial artery and/or cephalic vein at the wrist, avoiding more complex or staged procedures and preserving upper arm sites for future use. A proximal radial artery inflow procedure is recommended.

Safety of elective management of synchronous aortic disease with simultaneous thoracic and aortic stent graft placement.

BACKGROUND: Simultaneous treatment of multilevel aortic disease is controversial due to the theoretic increase in morbidity. This study was conducted to define the outcomes in patients treated electively with simultaneous thoracic endovascular aortic aneurysm repair (TEVAR) and abdominal aortic endovascular endografting for synchronous aortic pathology. METHODS: Patients treated with simultaneous TEVAR and endovascular aneurysm repair (T&E) at the University of Florida were identified from a prospectively maintained endovascular aortic registry and compared with those treated with TEVAR alone (TA). The study excluded patients with urgent or emergency indications, thoracoabdominal or mycotic aneurysm, and those requiring chimney stents, fenestrations, or visceral debranching procedures. Demographics, anatomic characteristics, operative details, and periprocedural morbidity were recorded. Mortality and reintervention were estimated using life-table analysis. RESULTS: From 2001 to 2011, 595 patients underwent TEVAR, of whom 457 had elective repair. Twenty-two (18 men, 82%) were identified who were treated electively with simultaneous T&E. Mean ± standard deviation age was 66 ± 9 years, and median follow-up was 8.8 months (range, 1-34 months). Operative indications for the procedure included dissection-related pathology in 10 (45%) and various combinations of degenerative etiologies in 12 (55%). Compared with TA, T&E patients had significantly higher blood loss (P < .0001), contrast exposure (P < .0001), fluoroscopy time (P < .0001), and operative time (P < .0001). The temporary spinal cord ischemia rate was 13.6% (n = 3) for the T&E group and 6.0% for TA (P = .15); however, the permanent spinal cord ischemia rate was 4% for both groups (P = .96). The 30-day mortality for T&E was 4.5% (n = 1) compared with 2.1% (n = 10) for TA. Temporary renal injury (defined by a 25% increase over baseline creatinine) occurred in two T&E patients (9.1%), with none requiring permanent hemodialysis; no significant difference was noted between the two groups (P = .14). One-year mortality and freedom from reintervention in the T&E patients were 81% and 91%, respectively. CONCLUSIONS: Acceptable short-term morbidity and mortality can be achieved with T&E compared with TA, despite longer operative times, greater blood loss, and higher contrast exposure. There was a trend toward higher rates of renal and spinal cord injury, so implementation of strategies to reduce the potential of these complications or consideration of staged repair is recommended. Short-term reintervention rates are low, but longer follow-up and greater patient numbers are needed to determine procedural durability and applicability.