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The Centers for Disease Control and Prevention has made the prevention of in-hospital Clostridium difficile infection a priority. However, whether there is a differential impact of Clostridium difficile on surgical patients remains undefined. Therefore, we quantified the procedure-specific association between postoperative Clostridium difficile and surgical outcomes to define opportunities for targeted quality improvement.We studied patients undergoing major cardiac, vascular, general, or oncologic procedures using the Vizient database from 2015 to 2019. Our primary exposure was postoperative Clostridium difficile infection. Our primary outcomes were postoperative length of stay, hospitalization cost, readmission, and in-hospital mortality. We used linear and logistic regression for risk adjustment.The incidence of Clostridium difficile infection was 1.6% (n = 6,506/397,750). Patients with Clostridium difficile were older, more comorbid, and more frequently underwent urgent surgery. The median postoperative length of stay was 7 days (interquartile range: 5-11 days), and it was 66% longer among those with Clostridium difficile (P.001). Similarly, the median hospitalization cost was $31,000 (interquartile range: $20,000-$49,000), and it was 51% greater among patients with Clostridium difficile (P.001). Postoperative Clostridium difficile was associated with more readmissions after coronary artery bypass grafting, small bowel resection, colectomy, gastrectomy, pancreatectomy, and infrainguinal bypass (adjusted odds ratio range: 1.4-1.7), but not after open aneurysm repair, suprainguinal bypass, or esophagectomy. Clostridium difficile was associated with increased mortality after coronary artery bypass grafting, small bowel resection, colectomy, and infrainguinal bypass (adjusted odds ratio range: 1.3-2.7), but not after open aneurysm repair, suprainguinal bypass, esophagectomy, gastrectomy, or pancreatectomy.Postoperative Clostridium difficile infection was differentially associated with increased length of stay, cost, readmissions, and mortality across specific procedures. This was most apparent after infrainguinal bypass, small bowel resection, colectomy, and coronary artery bypass grafting. Accordingly, a targeted Clostridium difficile reduction effort for these procedures may offer a more effective approach toward reducing infection rates.

End-stage kidney disease, the most advanced stage of chronic kidney disease (CKD), requires renal replacement therapy or kidney transplant to sustain life. To accomplish durable dialysis access, the creation of an arteriovenous fistula (AVF) has emerged as a preferred approach. Unfortunately, a significant proportion of patients that receive an AVF experience some form of hand dysfunction; however, the mechanisms underlying these side effects are not understood. In this study, we used nuclear magnetic resonance spectroscopy to investigate the muscle metabolome following iliac AVF placement in mice with CKD. To induce CKD, C57BL6J mice were fed an adenine-supplemented diet for 3 wk and then randomized to receive AVF or sham surgery. Two weeks following surgery, the quadriceps muscles were rapidly dissected and snap frozen for metabolite extraction and subsequent nuclear magnetic resonance analysis. Principal component analysis demonstrated clear separation between groups, confirming a unique metabolome in mice that received an AVF. AVF creation resulted in reduced levels of creatine, ATP, and AMP as well as increased levels of IMP and several tricarboxylic acid cycle metabolites suggesting profound energetic stress. Pearson correlation and multiple linear regression analyses identified several metabolites that were strongly linked to measures of limb function (grip strength, gait speed, and mitochondrial respiration). In summary, AVF creation generates a unique metabolome profile in the distal skeletal muscle indicative of an energetic crisis and myosteatosis.

The Society for Vascular Surgery Vascular Quality Initiative (VQI) has become an increasingly popular data source for retrospective observational vascular surgery studies. There are published guidelines on the reporting of data in such studies to promote transparency and rigor, but these have not been used to evaluate studies using VQI data. Our objective was to appraise the methodological reporting quality of studies using VQI data by evaluating their adherence to these guidelines.The Society for Vascular Surgery VQI publication repository was queried for all articles published in 2020. The REporting of studies Conducted using Observational Routinely-collected Health Data (RECORD) statement and the Journal of American Medical Association-Surgical Section (JAMA-Surgery) checklist were utilized to assess the quality of each article's reporting. Five and three items from the RECORD statement and JAMA-Surgery checklist were excluded, respectively, because they were either inapplicable or nonassessable. Journal impact factor (IF) was queried for each article to elucidate any difference in reporting standards between high and low IF journals.Ninety studies were identified and analyzed. The median score on the RECORD checklist was 6 (of 8). The most commonly missed item was discussing data cleaning methods (93% missed). The median score on the JAMA-Surgery checklist was 3 (of 7). The most commonly missed items were the identification of competing risks (98% missed), the use of a flow chart to clearly define sample exclusion and inclusion criteria (84% missed), and the inclusion of a solid research question and hypothesis (81% missed). There were no differences in JAMA-Surgery checklist or RECORD statement median scores among studies published in low vs high IF journals.Studies using VQI data demonstrate a poor to moderate adherence to reporting standards. Key areas for improvement in research reporting include articulating a clear hypothesis, using flow charts to clearly define inclusion and exclusion criteria, identifying competing risks, and discussing data cleaning methods. Additionally, future efforts should center on creating tailored instruments to better guide reporting in studies using VQI data.

Endovascular aneurysm repair conversion (EVAR-c) is increasingly reported and known to be technically complex and physiologically demanding. It has been proposed that pragmatic anthropomorphic measures such as psoas muscle area (PMA) may reliably quantify levels of preoperative frailty and be used to inform point of care clinical decision-making and patient discussions for a variety of complex operations. To date, there is mixed data supporting use of PMA as a prognostic factor in fenestrated endovascular and open abdominal aortic aneurysms (AAA) repairs; however, no literature exists evaluating the impact of preoperative PMA on EVAR-c results. Therefore, the purpose of this study was to review our EVAR-c experience and evaluate the association of PMA with perioperative and long-term mortality outcomes.A retrospective single-center review of all AAA repairs was performed (2002-2019) and EVAR-c procedures were subsequently analyzed (n = 153). Cross-sectional PMA at the mid-body of the L3 vertebrae was measured. The lowest PMA tertile was used as a threshold value to designate patients as having "low" PMA (n = 51) and this cohort was subsequently compared to subjects with "normal" PMA (n = 102). Cox proportional hazards modeling was used to estimate covariate association with all-cause mortality.Patients with low PMA were older (77 vs. 72 years; P = 0.002), more likely to be female (27% vs. 5%; P 0.001), and had reduced body mass index (26 vs. 29 kg/mAmong EVAR-c patients, subjects with low preoperative PMA had higher rates of postoperative complications and worse overall survival. PMA assessments may be a useful adjunct to supplement traditional risk-stratification strategies when patients are being considered for EVAR-c.

Patients with abdominal aortic aneurysm (AAA) can choose open repair or endovascular repair (EVAR). While EVAR is less invasive, it requires lifelong surveillance and more frequent aneurysm-related reinterventions than open repair. A decision aid may help patients receive their preferred type of AAA repair.To determine the effect of a decision aid on agreement between patient preference for AAA repair type and the repair type they receive.In this cluster randomized trial, 235 patients were randomized at 22 VA vascular surgery clinics. All patients had AAAs greater than 5.0 cm in diameter and were candidates for both open repair and EVAR. Data were collected from August 2017 to December 2020, and data were analyzed from December 2020 to June 2021.Presurgical consultation using a decision aid vs usual care.The primary outcome was the proportion of patients who had agreement between their preference and their repair type, measured using χ2 analyses, κ statistics, and adjusted odds ratios.Of 235 included patients, 234 (99.6%) were male, and the mean (SD) age was 73 (5.9) years. A total of 126 patients were enrolled in the decision aid group, and 109 were enrolled in the control group. Within 2 years after enrollment, 192 (81.7%) underwent repair. Patients were similar between the decision aid and control groups by age, sex, aneurysm size, iliac artery involvement, and Charlson Comorbidity Index score. Patients preferred EVAR over open repair in both groups (96 of 122 [79%] in the decision aid group; 81 of 106 [76%] in the control group; P = .60). Patients in the decision aid group were more likely to receive their preferred repair type than patients in the control group (95% agreement [93 of 98] vs 86% agreement [81 of 94]; P = .03), and κ statistics were higher in the decision aid group (κ = 0.78; 95% CI, 0.60-0.95) compared with the control group (κ = 0.53; 95% CI, 0.32-0.74). Adjusted models confirmed this association (odds ratio of agreement in the decision aid group relative to control group, 2.93; 95% CI, 1.10-7.70).Patients exposed to a decision aid were more likely to receive their preferred AAA repair type, suggesting that decision aids can help better align patient preferences and treatments in major cardiovascular procedures.ClinicalTrials.gov Identifier: NCT03115346.

Chronic kidney disease (CKD) accelerates the development of atherosclerosis, decreases muscle function, and increases the risk of amputation or death in patients with peripheral artery disease (PAD). However, the cellular and physiological mechanisms underlying this pathobiology are ill-defined. Recent work has indicated that tryptophan-derived uremic toxins, many of which are ligands for the aryl hydrocarbon receptor (AHR), are associated with adverse limb outcomes in PAD. We hypothesized that chronic AHR activation, driven by the accumulation of tryptophan-derived uremic metabolites, may mediate the myopathic condition in the presence of CKD and PAD. Both PAD patients with CKD and mice with CKD subjected to femoral artery ligation (FAL) displayed significantly higher mRNA expression of classical AHR-dependent genes (Cyp1a1,Cyp1b1, andAldh3a1) when compared to either muscle from the PAD condition with normal renal function (PmKO) significantly improved limb muscle perfusion recovery and arteriogenesis, preserved vasculogenic paracrine signaling from myofibers, increased muscle mass and contractile function, as well as enhanced mitochondrial oxidative phosphorylation and respiratory capacity in an experimental model of PAD/CKD. Moreover, viral-mediated skeletal muscle-specific expression of a constitutively active AHR in mice with normal kidney function exacerbated the ischemic myopathy evidenced by smaller muscle masses, reduced contractile function, histopathology, altered vasculogenic signaling, and lower mitochondrial respiratory function. These findings establish chronic AHR activation in muscle as a pivotal regulator of the ischemic limb pathology in PAD. Further, the totality of the results provide support for testing of clinical interventions that diminish AHR signaling in these conditions.

Background Chronic limb-threatening ischemia (CLTI) can be associated with dismal outcomes but there are limited real-world data to further define the impact of end-stage kidney disease (ESKD) on outcomes nationally in this subset of patients. We sought to characterize national patterns of inpatient treatment of CLTI and compare outcomes in patients without ESKD. Methods The National Inpatient Sample was queried from 2015-2018 for all hospital admissions including treatment for CLTI. Mixed-effects linear and logistic regression models were used to estimate the effect of ESKD on outcomes and treatment choice. Results We identified 11 652 hospital admissions with CLTI alone and 2705 with CLTI + ESKD. Hospital admissions with CLTI + ESKD patients included patients who were younger (66 vs 69 years, P < .0001), less likely to be white (39% vs 63%, P < .0001), and more likely to reside in lower income large metropolitan areas. Admissions for CLTI + ESKD patients had a lower likelihood of open arterial reconstruction (OR .40, P < .0001) and a higher likelihood of endovascular revascularization or major limb amputation (OR 1.70, P < .0001). Admissions for CLTI + ESKD also had a 4.5- and 1.5-fold higher odds of in-hospital death and complications. These findings were associated with a longer LOS ( P < .0001), increased probability of discharge to rehabilitation facility (50% vs 41%, P < .0001), and greater hospital charges (median, $107 K vs $85 K, P < .0001). Conclusions Compared to hospital admissions for patients without ESKD, admissions for patients with CLTI + ESKD demonstrated distinctive demographic characteristics, a lower likelihood of open revascularization and a higher likelihood of endovascular revascularization and major limb amputation. Chronic limb-threatening ischemia + ESKD hospital admissions showed worse overall outcomes and greater resource utilization compared to CLTI admissions without ESKD.

Background Carotid artery stenting is an alternative to carotid endarterectomy, especially in patients deemed to have significant anatomic or medical risk for the latter. There is scant literature, however, on indications for and outcomes of carotid stent (CAS) explant. We sought to determine indications and outcomes of CAS explant at our institution. Methods We queried a prospectively maintained institutional vascular surgery database as well as hospital records to identify patients undergoing carotid stent explant from 2010–2020. Ten patients were identified. Their charts were reviewed to obtain demographic, comorbidity, procedural, and outcomes data. Data of particular interest were preoperative atherosclerotic factors, indications for CAS explant, carotid repair strategy, and 30-day post-procedural complications. Data were analyzed for ranges and means. Results Ten patients were identified. Comorbidity was common: all patients had at least 1 atherosclerotic risk factor, with hypertension and hypercholesterolemia being the most common. Seven (70.0%) patients had recurrent stenosis as the indication for explant. Seven (70.0%) presented symptomatically. Five (50.0%) cases of restenosis had been refractory to angioplasty. There were 3 (30.0%) instances of CAS explant due to infection. Only 1 (12.5%) index CAS was performed at our institution. There was a mean hospital length of stay of 4.5 days. One patient had vocal cord paralysis requiring no intervention. There was no (0%) 30-day mortality, stroke, or postoperative wound infections. Conclusions Our series had 0% 30-day mortality, stroke, and postoperative wound infection suggesting that CAS explant may be performed safely. Our series is small but represents the largest single institution series to date. This procedure may become increasingly common in the coming years with the more frequent use of CAS; additional data is needed to rigorously understand outcomes.

Spinal cord ischemia (SCI) is a dreaded complication of thoracic and complex endovascular aortic repair (TEVAR/cEVAR). Controversy exists surrounding cerebrospinal fluid drain (CSFD) use, especially preoperative prophylactic placement, owing to concerns regarding catheter-related complications. However, these risks are balanced by the widely accepted benefits of CSFDs during open repair to prevent and/or rescue patients with SCI. The importance of this issue is underscored by the paucity of data on CSFD practice patterns, limiting the development of practice guidelines. Therefore, the purpose of the present analysis was to evaluate the differences between patients who developed SCI despite preoperative CSFD placement and those treated with therapeutic postoperative CSFD placement.All elective TEVAR/cEVAR procedures for degenerative aneurysm pathology in the Society for Vascular Surgery Vascular Quality Initiative from 2014 to 2019 were analyzed. CSFD use over time, the factors associated with preoperative prophylactic vs postoperative therapeutic CSFD placement in patients with SCI (transient or permanent), and outcomes were evaluated. Survival differences were estimated using the Kaplan-Meier method.A total of 3406 TEVAR/cEVAR procedures met the inclusion criteria, with an overall SCI rate of 2.3% (n = 88). The SCI rate decreased from 4.55% in 2014 to 1.43% in 2018. Prophylactic preoperative CSFD use was similar over time (2014, 30%; vs 2018, 27%; P = .8). After further exclusions to evaluate CSFD use in those who had developed SCI, 72 patients were available for analysis, 48 with SCI and prophylactic CSFD placement and 24 with SCI and therapeutic CSFD placement. Specific to SCI, the patient demographics and comorbidities were not significantly different between the prophylactic and therapeutic groups, with the exception of previous aortic surgery, which was more common in the prophylactic CSFD cohort (46% vs 23%; P .001). The SCI outcome was significantly worse for the therapeutic group because 79% had documented permanent paraplegia at discharge compared with 54% of the prophylactic group (P = .04). SCI patients receiving a postoperative therapeutic CSFD had had worse survival than those with a preoperative prophylactic CSFD (50% ± 10% vs 71% ± 9%; log-rank P = .1; Wilcoxon P = .05).Prophylactic CSFD use with TEVAR/cEVAR remained stable during the study period. Of the SCI patients, postoperative therapeutic CSFD placement was associated with worse sustained neurologic outcomes and overall survival compared with preoperative prophylactic CSFD placement. These findings highlight the need for a randomized clinical trial to examine prophylactic vs therapeutic CSFD placement in association with TEVAR/cEVAR.

Spinal cord ischemia (SCI) after thoracic endovascular aortic repair (TEVAR) can cause permanent neurologic deficits and poor long-term survival. Targeted treatment of new SCI symptoms after TEVAR (rescue therapy [RT]) might improve/resolve neurologic symptoms but few data characterize the association of specific interventions with SCI outcomes. We evaluated the effectiveness of post-TEVAR RT at our tertiary aortic center.Our institutional TEVAR database was reviewed for SCI incidence and details of RT. This included cerebrospinal fluid drainage (CSFD), medical therapy, and optimization of spinal cord oxygen delivery. SCI outcomes were categorized at discharge as paralysis/paraparesis and temporary/permanent.Nine hundred forty-three TEVAR procedures were performed in 869 patients from 2011 to 2020. Post-TEVAR SCI occurred in 7.8% (n = 74) with permanent paraplegia in 1.5%. Older patient age, chronic obstructive pulmonary disease, and previous abdominal aortic surgery were predictive of SCI. Half (n = 37) of SCI episodes resulted in only temporary paralysis/paraparesis. Rescue postoperative cerebrospinal fluid drains were implanted in 3.7% (n = 35) of procedures and was predicted by higher American Society of Anesthesiologists class, lower serum hemoglobin level, elevated international normalized ratio, bilateral iliac artery occlusion, nonelective procedures, and penetrating atherosclerotic ulcer/intramural hematoma indication. The most commonly used RTs were emergent placement of or increased drainage from an existing cerebrospinal fluid drain (87.8%), induced/permissive hypertension (77.0%), corticosteroid bolus (36.5%), and naloxone infusion (33.8%). Neurologic improvement occurred in 68.9% (n = 51/74). New/increased drainage was associated with improved SCI outcome.Permanent paraplegia from post-TEVAR SCI is rare (1.5%). Older patients with comorbidities carry greater post-TEVAR SCI risk. SCI symptoms improved/resolved with CSFD and multimodal RT in 68.9% of patients, but no intervention was independently associated with improvement. TEVAR centers should have robust protocols for timely and safe CSFD placement to augment RT strategies for SCI.

Chronic kidney disease is a major public health problem, and the prevalence of end-stage renal disease (ESRD) requiring chronic renal replacement therapies such as hemodialysis continues to increase. Autogenous arteriovenous fistula (AVF) placement remains a primary vascular access option for ESRD patients. Unfortunately, approximately half of the hemodialysis patients experience dialysis access-related hand dysfunction (ARHD), ranging from subtle paresthesia to digital gangrene. Notably, the underlying biologic drivers responsible for ARHD are poorly understood, and no adequate animal model exists to elucidate the mechanisms and/or develop novel therapeutics for the prevention/treatment of ARHD. Herein, we describe a new mouse model in which an AVF is created between the left common iliac artery and vein, thereby facilitating the assessment of limb pathophysiology. The microsurgery includes vessel isolation, longitudinal venotomy, creation of arteriovenous anastomosis, and venous reconstruction. Sham surgeries include all the critical steps except for AVF creation. Iliac AVF placement results in clinically relevant alterations in central hemodynamics, peripheral ischemia, and impairments in hindlimb neuromotor performance. This novel preclinical AVF model provides a useful platform that recapitulates common neuromotor perturbations reported by hemodialysis patients, allowing researchers to investigate the mechanisms of ARHD pathophysiology and test potential therapeutics.

Background The efficacy of thoracic endovascular aortic repair (TEVAR) of chronic type B aortic dissection (cTBAD) is controversial. Only limited evidence describes temporal anatomic changes after TEVAR for cTBAD and their relationship to outcomes. We sought to investigate early aortic remodeling events after TEVAR for cTBAD with thoracic aneurysm and determine the association with reintervention and survival. Methods Records from 95 cTBAD patients undergoing TEVAR from 2005 to 2017 were reviewed. Using 3-dimensional centerline analysis, anatomic phenotyping of the thoracoabdominal aorta was performed. Reverse aortic remodeling (RAR) was defined by a ≥5-mm reduction in maximal thoracic aortic diameter. Kaplan-Meier analysis estimated freedom from reintervention and survival. Results Visceral segment dissection involvement was present in 89% of patients (n = 85), and the mean preoperative thoracic diameter was 63 mm (SD, 10). Complete thoracic false lumen thrombosis occurred in 71% of patients (n = 67), whereas abdominal false lumen thrombosis was documented in 60% (n = 57) by 6 months. RAR occurred in 41%. Aortic reintervention rate was 39% (n = 37). The 1- and 3-year freedom from reintervention was significantly higher in subjects experiencing early RAR (log-rank P = .02), but reintervention did not impact overall survival (log-rank P = .9). Similarly, overall survival was similar between patients with or without RAR (log-rank P = .4). Conclusions Early RAR is associated with decreased rates of reintervention; however, overall survival is not impacted by these changes. TEVAR for cTBAD results in a high rate of reintervention, which mandates vigilant surveillance protocols.

Objective Previous publications have clearly established a correlation between timing of thoracic endovascular aortic repair (TEVAR) and complications after treatment of complicated acute type B aortic dissection (ATBAD). However, the temporal association of TEVAR with morbidity after uncomplicated presentations is poorly understood and has not previously been examined using real-world national data. Therefore, the objective of this analysis was to determine whether TEVAR timing of uncomplicated ATBAD (UATBAD) is associated with postoperative complications. Methods The Vascular Quality Initiative TEVAR and complex endovascular aneurysm repair registry was analyzed from 2010 to 2019. Procedures performed for non-dissection-related disease as well as for ATBAD with malperfusion or rupture were excluded. Because of inherent differences between timing cohorts, propensity score matching was performed to ensure like comparisons. Univariate and multivariable analysis after matching was used to determine differences between timing groups (symptom onset to TEVAR: acute, 1-14 days; subacute, 15-90 days) for postoperative mortality, in-hospital complications, and reintervention. Results A total of 688 cases meeting inclusion criteria were identified. After matching 187 patients in each of the 1- to 14-day and 15- to 90-day treatment groups, there were no statistically significant differences between groups. On univariate analysis, the 1- to 14-day treatment group had a higher proportion of cases requiring reintervention within 30 days (15.3%) compared with UATBAD patients undergoing TEVAR within 15 to 90 days (5.2%; P = .02). There was also a difference (P = .007) at 1 year, with 33.8% of the 1- to 14-day UATBAD patients undergoing reintervention compared with 14.5% for the 15- to 90-day group. There were no statistically significant differences on multivariable analysis for long-term survival, complications, or long-term reintervention. There was a trend toward significance (P = .08) with the 1- to 14-day group having 2.3 times the odds of requiring an in-hospital reintervention compared with the 15- to 90-day group. Conclusions Timing of TEVAR for UATBAD does not appear to predict mortality or postoperative complications. However, there is a strong association between repair within 1 to 14 days and higher risk of reintervention. This may in part be related to the 1- to 14-day group's representing an inherently higher anatomic or physiologic risk population that cannot be entirely accounted for with propensity analysis. The role of optimal timing to intervention should be incorporated into future study design of TEVAR trials for UATBAD.

Background Superior mesenteric artery aneurysms (SMAAs) are a rare clinical problem that can be associated with significant morbidity and mortality. The optimal surgical approach for both mycotic and degenerative SMAAs remains poorly defined. The study was designed to review our institutional experience and develop a treatment algorithm. Methods A single-institution, retrospective review was performed to document presentation, treatment, and outcomes of patients undergoing surgical repair of SMAAs from 2003 to 2020. The primary end-point was 30-day mortality, and secondary end-points included complications, patency, freedom from reinfection, freedom from reintervention, and survival. Results Eighteen patients (mean age: 46 ± 16 yrs; 50% male; mean diameter 2.4 ± 2.0 cm) underwent treatment of mycotic (50%) or degenerative (50%) SMAAs. Abdominal pain (66%) was the most common presenting symptom, and the diagnosis was confirmed with CT arteriography. Endocarditis secondary to intravenous drug abuse was responsible for most (88%) of the mycotic SMAAs, with a majority (66%) having positive cultures and Streptococcus being the most common organism. The majority (61%) of patients underwent urgent or emergent repair with aneurysmectomy and interposition saphenous vein bypass being the most common treatment of mycotic SMAAs while aneurysmectomy and prosthetic bypass were used most frequently for degenerative aneurysms. The operative mortality rate was 6% with a major complication rate of 17% (n = 3 patients: respiratory failure/reintubation-1, pulmonary embolism-1, necrotizing pancreatitis/graft disruption and death-1). The single death occurred in a patient with a degenerative aneurysm that developed postoperative pancreatitis and multiple organ dysfunction. The mean clinical follow-up time was 25 ± 48 (95% CI 1–48) months. The estimated primary patency, freedom from reinfection, and freedom from reintervention were 93 ± 7 %, 94 ± 5%, and 94 ± 5%, respectively, at 1 year. The overall mean survival was 55 ± 51 (95% CI 30–80) months with an estimated survival at 3 years of 77 ± 10%. Conclusions SMAAs associated with both degenerative and mycotic etiologies can be treated using a variety of surgical approaches with acceptable morbidity and mortality. Mycotic SMAAs should likely be repaired, regardless of size, while the indications for asymptomatic, degenerative aneurysms remain to be defined by further natural history studies.

Objective Hemodialysis access-related hand dysfunction is a common clinical feature of patients with chronic kidney disease (CKD) after arteriovenous fistula (AVF) placement. The heterogeneity in symptoms and the lack of a predictive association with changes in hemodynamic alterations precipitated by the AVF suggest that other factors are involved in the mechanisms responsible for causing hand and limb dysfunction postoperatively. To the best of our knowledge, no suitable animal models have provided a platform for performing preclinical experiments designed to elucidate the biologic drivers of access-related hand dysfunction. Therefore, our objective was to develop a novel murine AVF model that could be used to study dialysis access-related limb dysfunction. Methods Male 8-week-old C57BL/6J mice (n = 15/group) were exposed to either an adenine-supplemented diet to induce CKD or casein-based chow (control). Four weeks after the diet intervention, the mice were randomly assigned to receive an iliac AVF (n = 10/group) or sham surgery (n = 5/group) on the left hindlimb. The mice were sacrificed 2 weeks after surgery, and AVF specimens and hindlimb skeletal muscles were collected for further analysis. Results Before AVF or sham surgery, the glomerular filtration rates were significantly reduced and the blood urea nitrogen levels were significantly elevated in the CKD groups compared with the controls (P < .05). AVF surgery was associated with an ∼80% patency rate among the survivors (four control and three CKD mice died postoperatively). Patency was verified by changes in hemodynamics using Doppler ultrasound imaging and altered histologic morphology. Compared with sham surgery, AVF surgery reduced ipsilateral hindlimb perfusion to the tibialis anterior muscle (20%-40%) and paw (40%-50%), which remained stable until euthanasia. Analysis of gastrocnemius muscle mitochondrial respiratory function uncovered a significant decrease (40%-50%) in mitochondrial function in the AVF mice. No changes were found in the muscle mass, myofiber cross-sectional area, or centrally nucleated fiber proportion in the extensor digitorum longus and soleus muscles between the sham and AVF mice. Conclusions The results from the present study have demonstrated that iliac AVF formation is a practical animal model that facilitates examination of hemodialysis access-related limb dysfunction. AVF surgery produced the expected hemodynamic changes, and evaluation of the limb muscle revealed a substantial mitochondrial impairment that was present without changes in muscle size., Clinical Relevance Autogenous arteriovenous fistula creation remains the preferred vascular access option for patients requiring chronic hemodialysis therapy. However, access-related hand dysfunction (ARHD) remains highly prevalent in this population. Clinical management of the disability is difficult because of symptom heterogeneity and limited treatment options. Additionally, the current preclinical models do not adequately replicate the pathologic condition to allow for investigation of underlying mechanisms and to test new therapies. Therefore, medical progress has been marginal. In the present study, we have outlined a novel murine model to study ARHD and described the associated mitochondrial impairments, providing a unique tool for preclinical therapeutic development., Visual abstract

The Vascular Implant Surveillance and Interventional Outcomes Network (VISION) is a Coordinated Registry Network (CRN) a member of Medical Device Epidemiology Network, a U.S. Food and Drug Administration (FDA)-supported global public-private partnership that seeks to advance the collection and use of real-world data to improve patient outcomes. The VISION CRN began in September 2015 and held its first strategic meeting on September 10, 2018, at the FDA headquarters in Silver Spring, Maryland. VISION is a collaboration of the Vascular Quality Initiative (VQI), the FDA, and other stakeholders. At this annual meeting, leaders from the FDA, VQI, industry representatives, population health researchers, and regulatory science experts gathered to discuss strategic goals and opportunities for VISION. One of the key focus areas for VISION is linkage of VQI registry data to Medicare, longitudinal data sources maintained by various states, and other relevant data sources, as a model for efficient, cost-saving, and effectual evidence generation and appraisal. This would provide the means to expand data collection, assess long-term procedural outcomes across the carotid, lower extremity, aortic, and venous intervention datasets, and execute registry-based trials through the CRN structure in an efficient, cost-effective manner. Looking forward, VISION strives to validate long-term outcome data in the VQI using industry datasets, in hopes of using CRNs to make device regulatory decisions. With the guidance of a steering committee, VISION will provide vascular surgeons, industry, and regulators the appropriate data to improve care for patients with vascular disease.