An Analysis of Water Used and Wasted at Operating Room (OR) Scrub Sinks and Call to Action for Reducing Water Waste.

OBJECTIVE: To model the volume of water used and wasted during wet scrubs at operating room (OR) scrub sinks and identify factors for reducing water waste. BACKGROUND: Wasteful consumption of water by US healthcare systems has not been well characterized. METHODS: This is a two-component observational study. The first was an observational study of handwashing practices and water usage at scrub sinks in the OR at a single medical center. The second component was a series of two anonymous surveys of surgeons and OR staff to assess hand scrub practices and perspectives. Data from both components were used to estimate the volume of water used and wasted annually at OR scrub sinks. RESULTS: The median total volume of water wasted at OR scrub sinks for 34,554 cases over one year is 337,595.6 L (interquartile range 139,010.0;911,210.5). This represents approximately 34.2% of the total volume of water usage associated with wet scrubs (i.e.,water used during scrubbing and wasted after the conclusion of the scrub). Other pertinent findings are that attending surgeons and OR staff perform water scrubs in 25.9% of cases; there are significant differences in scrub type preferences among OR users; the median volume of water wasted in a single wet scrub at timer-controlled sinks is 10 L; and significantly more water is wasted at timer-controlled sinks than knee-operated sinks. CONCLUSIONS: OR wet scrubs are a source of enormous water waste. We identified scrub sink characteristics and OR user beliefs and behaviors as modifiable factors for water waste reduction. We encourage all institutions and OR users to carefully examine their facility characteristics and practices to implement plans that will conserve water without compromising patient safety.

2024 ACC/AHA/AACVPR/APMA/ABC/SCAI/SVM/SVN/SVS/SIR/VESS Guideline for the Management of Lower Extremity Peripheral Artery Disease: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines.

AIM: The "2024 ACC/AHA/AACVPR/APMA/ABC/SCAI/SVM/SVN/SVS/SIR/VESS Guideline for the Management of Lower Extremity Peripheral Artery Disease" provides recommendations to guide clinicians in the treatment of patients with lower extremity peripheral artery disease across its multiple clinical presentation subsets (ie, asymptomatic, chronic symptomatic, chronic limb-threatening ischemia, and acute limb ischemia). METHODS: A comprehensive literature search was conducted from October 2020 to June 2022, encompassing studies, reviews, and other evidence conducted on human subjects that was published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through May 2023 during the peer review process, were also considered by the writing committee and added to the evidence tables where appropriate. STRUCTURE: Recommendations from the "2016 AHA/ACC Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with peripheral artery disease have been developed.

2024 ACC/AHA/AACVPR/APMA/ABC/SCAI/SVM/SVN/SVS/SIR/VESS Guideline for the Management of Lower Extremity Peripheral Artery Disease: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines.

AIM: The "2024 ACC/AHA/AACVPR/APMA/ABC/SCAI/SVM/SVN/SVS/SIR/VESS Guideline for the Management of Lower Extremity Peripheral Artery Disease" provides recommendations to guide clinicians in the treatment of patients with lower extremity peripheral artery disease across its multiple clinical presentation subsets (ie, asymptomatic, chronic symptomatic, chronic limb-threatening ischemia, and acute limb ischemia). METHODS: A comprehensive literature search was conducted from October 2020 to June 2022, encompassing studies, reviews, and other evidence conducted on human subjects that was published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through May 2023 during the peer review process, were also considered by the writing committee and added to the evidence tables where appropriate. STRUCTURE: Recommendations from the "2016 AHA/ACC Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with peripheral artery disease have been developed.

Cocoa flavanols, Nrf2 activation, and oxidative stress in peripheral artery disease: mechanistic findings in muscle based on outcomes from a randomized trial.

The pathophysiology of muscle damage in peripheral artery disease (PAD) includes increased oxidant production and impaired antioxidant defenses. Epicatechin (EPI), a naturally occurring flavanol, has antioxidant properties that may mediate the beneficial effects of natural products such as cocoa. In a phase II randomized trial, a cocoa-flavanol-rich beverage significantly improved walking performance compared with a placebo in people with PAD. In the present work, the molecular mechanisms underlying the therapeutic effect of cocoa flavanols were investigated by analyzing baseline and follow-up muscle biopsies from participants. Increases in nuclear factor erythroid 2-related factor 2 (Nrf2) target antioxidants heme oxygenase-1 (HO-1) and NAD(P)H dehydrogenase [quinone] 1 (NQO1) in the cocoa group were significantly associated with reduced accumulation of central nuclei, a myopathy indicator, in type II muscle fibers (P = 0.017 and P = 0.023, respectively). Protein levels of the mitochondrial respiratory complex III subunit, cytochrome b-c1 complex subunit 2 (UQCRC2), were significantly higher in the cocoa group than in the placebo group (P = 0.032), and increases in UQCRC2 were significantly associated with increased levels of Nrf2 target antioxidants HO-1 and NQO1 (P = 0.001 and P = 0.035, respectively). Exposure of non-PAD human myotubes to ex vivo serum from patients with PAD reduced Nrf2 phosphorylation, an indicator of activation, increased hydrogen peroxide production and oxidative stress, and reduced mitochondrial respiration. Treatment of myotubes with EPI in the presence of serum from patients with PAD increased Nrf2 phosphorylation and protected against PAD serum-induced oxidative stress and mitochondrial dysfunction. Overall, these findings suggest that cocoa flavanols may enhance antioxidant capacity in PAD via Nrf2 activation.NEW & NOTEWORTHY The current study supports the hypothesis that in people with PAD, cocoa flavanols activate Nrf2, thereby increasing antioxidant protein levels, protecting against skeletal muscle damage, and increasing mitochondrial protein abundance. These results suggest that Nrf2 activation may be an important therapeutic target for improving walking performance in people with PAD.

Discordance of patient-reported outcome measures with objectively assessed walking decline in peripheral artery disease.

OBJECTIVE: Among people with peripheral artery disease (PAD), perceived change in walking difficulty over time, compared with people without PAD, is unclear. Among people reporting no change in walking difficulty over time, differences in objectively measured change in walking performance between people with and without PAD are unknown. METHODS: A total of 1289 participants were included. Eight hundred seventy-four participants with PAD (aged 71.1 ± 9.1 years) were identified from noninvasive vascular laboratories and 415 without PAD (aged 69.9 ± 7.6 years) were identified from people with normal vascular laboratory testing or general medical practices in Chicago. The Walking Impairment Questionnaire and 6-minute walk were completed at baseline and 1-year follow-up. The Walking Impairment Questionnaire assessed perceived difficulty walking due to symptoms in the calves or buttocks on a Likert scale (range, 0-4). Symptom change was determined by comparing difficulty reported at 1-year follow-up to difficulty reported at baseline. RESULTS: At 1-year follow-up, 31.9% of participants with and 20.6% of participants without PAD reported walking difficulty that was improved (P < .01), whereas 41.2% vs 55%, respectively, reported walking difficulty that was unchanged (P < .01). Among all reporting no change in walking difficulty, participants with PAD declined in 6-minute walk, whereas participants without PAD improved (-10 vs +15 meters; mean difference, -25; 95% confidence interval, -38 to -13; P < .01). CONCLUSIONS: Most people with PAD reported improvement or no change in walking difficulty from calf or buttock symptoms at one-year follow-up. Among all participants who perceived stable walking ability, those with PAD had significant greater declines in objectively measured walking performance, compared with people without PAD.

Inflammatory Cell Dynamics after Murine Femoral Artery Wire Injury: A Multi-Parameter Flow Cytometry-Based Analysis.

An acute inflammatory response following arterial surgery for atherosclerosis, such as balloon angioplasty, stenting, and surgical bypass, is an important driver of neointimal hyperplasia after arterial injury, which leads to recurrent ischemia. However, a comprehensive understanding of the dynamics of the inflammatory infiltrate in the remodeling artery is difficult to attain due to the shortcomings of conventional methods such as immunofluorescence. We developed a 15-parameter flow cytometry method to quantitate leukocytes and 13 leukocyte subtypes in murine arteries at 4 time points after femoral artery wire injury. Live leukocyte numbers peaked at 7 days, which preceded the peak neointimal hyperplasia lesion at 28 days. Neutrophils were the most abundant early infiltrate, followed by monocytes and macrophages. Eosinophils were elevated after 1 day, while natural killer and dendritic cells gradually infiltrated over the first 7 days; all decreased between 7 and 14 days. Lymphocytes began accumulating at 3 days and peaked at 7 days. Immunofluorescence of arterial sections demonstrated similar temporal trends of CD45+ and F4/80+ cells. This method allows for the simultaneous quantitation of multiple leukocyte subtypes from small tissue samples of injured murine arteries and identifies the CD64+Tim4+ macrophage phenotype as being potentially important in the first 7 days post-injury.

Open aortic septectomy for complicated type B aortic dissection.

Malperfusion is a complication of acute aortic dissection associated with substantially increased morbidity and mortality. Although endovascular treatment of the dissection with a stent graft to cover the intimal tear and reexpand the true lumen will often be sufficient to treat distal malperfusion, persistent or delayed malperfusion will necessitate additional interventions. Endovascular strategies to increase true lumen expansion include bare metal dissection stent placement and percutaneous fenestration. However, for patients with anatomy not amenable to an endovascular approach, alternative techniques are required. We describe two cases of complicated acute aortic dissection due to partial false lumen thrombosis treated with open aortic septectomy. Although an uncommon procedure, open septectomy can be useful for patients with malperfusion syndromes without appropriate endovascular options.

Prosthetic vascular grafts engineered to combat calcification: Progress and future directions.

Calcification in prosthetic vascular conduits is a major challenge in cardiac and vascular surgery that compromises the long-term performance of these devices. Significant research efforts have been made to understand the etiology of calcification in the cardiovascular system and to combat calcification in various cardiovascular devices. Novel biomaterial design and tissue engineering strategies have shown promise in preventing or delaying calcification in prosthetic vascular grafts. In this review, we highlight recent advancements in the development of acellular prosthetic vascular grafts with preclinical success in attenuating calcification through advanced biomaterial design. We also discuss the mechanisms of action involved in the designs that will contribute to the further understanding of cardiovascular calcification. Lastly, recent insights into the etiology of vascular calcification will guide the design of future prosthetic vascular grafts with greater potential for translational success.

Identifying gaps in disease knowledge among patients with peripheral artery disease.

OBJECTIVE: An individual's understanding of disease risk factors and outcomes is important for the ability to make healthy lifestyle choices and decisions about disease treatment. Peripheral artery disease (PAD) is a condition with increasing global prevalence and high risk of adverse patient outcomes. This study seeks to understand the adequacy of disease understanding in patients with PAD. METHODS: This was an observational study of patients with PAD recruited from vascular surgery outpatient clinic and PAD clinical studies at a single academic medical center over an 8-month period. A 44-item paper survey assessed demographic and socioeconomic information, knowledge of personal medical history, PAD risk factors, consequences of PAD, and health education preferences. Patients with documented presence of PAD were offered the survey. Patients unable to complete the survey or provide informed consent were not considered eligible. Disease "awareness" was defined as correct acknowledgement of the presence or absence of a disease, including PAD, in the personal medical history. "PAD knowledge score" was the percentage of correct responses to questions on general PAD risk factors and consequences. Of 126 eligible patients, 109 participated. Bivariate analysis was used to study factors associated with awareness of PAD diagnosis. Factors associated with the PAD knowledge score were studied using the Pearson correlation coefficient, two-sample t test, or one-way analysis of variance. P value < .05 was considered statistically significant. RESULTS: The mean participant age was 69.4 ± 11.0 years, and 39.4% (n = 43) were female. Most participants (78.9%; n = 86) had critical limb-threatening ischemia. Only 65.4% (n = 70) of participants were aware of a diagnosis of PAD, which was less than their awareness of related comorbidities. Factors positively associated with PAD diagnosis awareness were female sex (81.4% vs 54.7%; P = .004) and history of percutaneous leg revascularization (78.6% vs 47.9%; P = .001). Among 17 patients who had undergone major leg amputation, 35% (n = 6) were unaware of a diagnosis of PAD. PAD knowledge scores correlated positively with an awareness of PAD diagnosis (59.1% vs 48.7%; P = .02) and negatively with a history of hypertension (53.4% vs 68.1%; P = .001). Most participants (86.5%; n = 90) expressed a desire to be further educated on PAD. The most popular education topics were dietary recommendations, causes, and treatment for PAD. CONCLUSIONS: Patients with PAD have deficits in their awareness of this diagnosis and general knowledge about PAD. Future research priorities should further define these deficits and their causes in order to inform new strategies that foster information-seeking behavior and effective educational programs for PAD.

Ankle-brachial index to monitor limb perfusion in patients with femoral venoarterial extracorporeal membrane oxygenation.

BACKGROUND: Limb ischemia is a major complication of femoral venoarterial extracorporeal membrane oxygenation (VA-ECMO). Use of ankle-brachial index (ABI) to monitor limb perfusion in VA-ECMO has not been described. We report our experience monitoring femoral VA-ECMO patients with serial ABI and the relationships between ABI and near infrared spectroscopy (NIRS). METHODS: This is a retrospective single-center review of consecutive adult patients placed on femoral VA-ECMO between January 2019 and October 2019. Data were collected on patients with paired ABI and NIRS values. Relationships between NIRS and ABI of the cannulated (E-NIRS and E-ABI) and non-cannulated legs (N-NIRS and N-ABI) along with the difference between legs (d-NIRS and d-ABI) were determined using Pearson correlation. RESULTS: Overall, 22 patients (mean age 56.5 ± 14.0 years, 72.7% male) were assessed with 295 E-ABI and E-NIRS measurements, and 273 N-ABI and N-NIRS measurements. Mean duration of ECMO support was 129.8 ± 78.3 h. ECMO-mortality was 13.6% and in-hospital mortality was 45.5%. N-ABI and N-NIRS were significantly higher than their ECMO counterparts (ABI mean difference 0.16, 95% confidence interval [CI]: 0.13-0.19, p < .0001; NIRS mean difference 2.51, 95% CI: 1.48-3.54, p < .0001). There was no correlation between E-ABI versus E-NIRS (r = .032, p = .59), N-ABI versus N-NIRS (r = .097, p = .11), or d-NIRS versus d-ABI (r = .11, p = .069). CONCLUSION: ABI is a quantitative metric that may be used to monitor limb perfusion and supplement clinical exams to identify limb ischemia in femorally cannulated VA-ECMO patients. More studies are needed to characterize the significance of ABI in femoral VA-ECMO and its value in identifying limb ischemia in this patient population.

Limb ischemia and bleeding in patients requiring venoarterial extracorporeal membrane oxygenation.

OBJECTIVE: Acute limb ischemia (ALI) and cannulation site bleeding are frequent complications of venoarterial (VA) extracorporeal membrane oxygenation (ECMO) and are associated with worse outcomes. The goals of this study were to assess our rates of ECMO-related ALI and bleeding and to evaluate the efficacy of strategies to prevent them, such as distal perfusion cannula (DPC) and ultrasound-guided cannulation. METHODS: This is a single-center retrospective cohort study of adult patients placed on peripheral VA-ECMO at a tertiary medical center between 2014 and 2018. ALI was defined as new ischemia of the extremity ipsilateral to arterial cannulation. Significant cannulation site bleeding was defined as excessive bleeding requiring intervention (eg, transfusion or reoperation). Univariate analyses were used to identify factors associated with ALI, bleeding, and in-hospital mortality. RESULTS: During the study period, 105 patients were placed on peripheral VA-ECMO (61.3% female; mean age, 54.9 ± 14.8 years). Nearly half (46.6%) had ECMO implantation in an extracorporeal cardiopulmonary resuscitation setting and 37 (44.0%) had a DPC. Average duration of support was 5.6 ± 5.0 days. Overall in-hospital mortality and death on ECMO support were 65.1% and 50%, respectively. ALI occurred in 21 (20%) and cannulation-related bleeding occurred in 24 (22.9%) patients who were treated with a total of 27 procedures, including thromboembolectomy (22.2%), vascular repair (18.5%), and fasciotomy (25.9%). On univariate analysis, cannulation in the operating room (odds ratio [OR], 0.25; 95% confidence interval [CI], 0.08-0.77; P = .02) was associated with decreased risk of ALI, whereas cannulation in the operating room (OR, 2.65; 95% CI, 1.09-6.45; P = .03) and cutdown approach (OR, 4.96; 95% CI, 2.32-10.61; P < .0001) were associated with increased risk of bleeding. Ultrasound-guided placement was associated with decreased risk of bleeding (OR, 0.81; 95% CI, 0.04-0.84; P = .03). DPC was not associated with either ALI (P = .47) or bleeding (P = .06). ALI (OR, 2.68; 95% CI 1.03-6.98; P = .04), age (OR, 1.94; 95% CI, 1.03-3.69; P = .04), and worse baseline heart failure (OR, 2.01; 95% CI, 1.02-3.97; P = .04) were associated with greater risk of in-hospital mortality. Ultrasound-guided cannulation (OR, 0.41; 95% CI, 0.20-0.87; P = .02) was associated with decreased risk of in-hospital mortality. CONCLUSIONS: ALI and significant bleeding are common occurrences after peripheral VA-ECMO cannulation. Whereas DPC placement did not significantly decrease risk of ALI, ultrasound-guided cannulation decreased the risk of bleeding. Cannulation in the operating room is associated with decreased risk of ALI at the expense of increased risk of bleeding. ALI, older age (≥65 years), and worse heart failure increased risk of in-hospital mortality.

The Comorbidity-Polypharmacy Score is an Objective and Practical Predictor of Outcomes and Mortality after Vascular Surgery.

BACKGROUND: The comorbidity-polypharmacy score (CPPS) was developed to quantify the severity of comorbidities of patients with geriatric trauma. CPPS is the sum of the number of medications and comorbidities, and is thus objective, user-friendly, and potentially adaptable to many clinical situations. We sought to understand if CPPS associates with outcomes and mortality after common vascular surgery procedures. METHODS: This is a retrospective single-center study. A total of 466 patients who underwent carotid endarterectomy, infrainguinal bypass, percutaneous lower extremity revascularization, or endovascular abdominal aortic aneurysm repair at a single medical center were included. CPPS were classified as mild, moderate, severe, and morbid based on scores of 0-7, 8-15, 15-21, and ≥21, respectively. End points were reinterventions, 30-day readmission, and mortality. We used chi-squared tests to analyze differences in categorical variables; Kruskal-Wallis tests to analyze differences in continuous variables; Kaplan-Meier estimation and Cox proportional hazard modeling to examine survival data; and receiver operator characteristic (ROC) curve analyses to assess sensitivity and specificity. RESULTS: The mean preoperative CPPS was 14.1 ± 6.1. Higher CPPS were associated with longer hospital and postoperative length of stay (P < 0.001). Severe and morbid CPPS categories had higher rates of ICU admission, reintervention, and 30-day readmission which did not reach statistical significance after correction for multiple comparisons. CPPS was independently associated with 1- and 5-year mortality in a multivariable Cox model (hazard ratio = 2.2, 95% confidence interval: 1.3-3.3). ROC analysis revealed C-statistics of 0.81 and 0.72 for 1-year and 5-year all-cause mortality, respectively (P < 0.001). CONCLUSIONS: CPPS is a simple and pragmatic clinical tool for quantifying risk of postoperative outcomes and mortality after common vascular surgery procedures. Further investigation is needed to validate the use of CPPS in enhancing existing predictors of patient outcomes and in serving as an adjunctive tool for determining resource allocation and discharge planning in patients who underwent vascular surgery.

Microbe-Derived Butyrate and Its Receptor, Free Fatty Acid Receptor 3, But Not Free Fatty Acid Receptor 2, Mitigate Neointimal Hyperplasia Susceptibility After Arterial Injury.

Background Arterial restenosis after vascular surgery is a common cause of midterm restenosis and treatment failure. Herein, we aim to investigate the role of microbe-derived butyrate, FFAR2 (free fatty acid receptor 2), and FFAR3 (free fatty acid receptor 3) in mitigating neointimal hyperplasia development in remodeling murine arteries after injury. Methods and Results C57BL/6 mice treated with oral vancomycin before unilateral femoral wire injury to deplete gut microbiota had significantly diminished serum and stool butyrate and more neointimal hyperplasia development after arterial injury, which was reversed by concomitant butyrate supplementation. Deficiency of FFAR3 but not FFAR2, both receptors for butyrate, exacerbated neointimal hyperplasia development after injury. FFAR3 deficiency was also associated with delayed recovery of the endothelial layer in vivo. FFAR3 gene expression was observed in multiple peripheral arteries, and expression was increased after arterial injury. Treatment of endothelial but not vascular smooth muscle cells with the pharmacologic FFAR3 agonist 1-methylcyclopropane carboxylate stimulated cellular migration and proliferation in scratch assays. Conclusions Our results support a protective role for butyrate and FFAR3 in the development of neointimal hyperplasia after arterial injury and delineate activation of the butyrate-FFAR3 pathway as a valuable strategy for the prevention and treatment of neointimal hyperplasia.

Identifying a Safe Carotid Stump Pressure Threshold for Selective Shunting During Carotid Endarterectomy.

BACKGROUND: There is no current consensus on the best criteria for selective shunting during carotid endarterectomy (CEA). The choice of continuous neurologic assessment during awake CEA, intraoperative electroencephalogram, or carotid stump pressure monitoring as the basis for shunt placement is primarily dependent on surgeon preference. Our goal is to define a safe stump pressure threshold as a guide for selective shunting. METHODS: The study is a single-surgeon retrospective review of consecutive patients who underwent CEA under general anesthesia with selective shunting based on intraoperative stump pressure measurements from 2001 to 2019. Demographic and periprocedural variables were analyzed using standard statistical techniques. RESULTS: Among 399 patients, 68% were male with a mean age of 70. One-third of the patients were symptomatic, with amaurosis fugax in 12%, transient ischemic attack in 7%, and stroke in 16%. In total, 60 (15%) patients underwent shunting: 34 for a confirmed preoperative acute ischemic stroke, 22 for a stump pressure <30 mm Hg, and 4 for other indications. Overall 30-day death, ischemic ipsilateral stroke, myocardial infarction, and cranial nerve palsy rates were 0.5%, 0.8%, 1.8%, and 1.0%, respectively. No strokes occurred due to hypoperfusion, and all stroke symptoms resolved prior to discharge with a mean length of stay of 1.6 days. CONCLUSIONS: This is one of the largest contemporary series of CEA using a 30 mm Hg threshold for selective shunting that demonstrated exceedingly low 30-day death and stroke events. Intraoperative carotid stump pressure measurements are a useful guide for selective shunting and reduction in perioperative stroke complications after CEA.

Predictors and Consequences of Loss to Follow-up after Vascular Surgery.

BACKGROUND: Loss to follow-up (LTF) after surgery impacts quality of care and can adversely affect short- and long-term clinical outcomes. This study identifies modifiable factors contributing to LTF after vascular surgery and the factors' effect on short- and long-term clinical outcomes. METHODS: This is a retrospective single-center cohort study of 440 consecutive adult patients who underwent carotid endarterectomy, infrainguinal bypass, percutaneous lower extremity revascularization, or endovascular aortic aneurysm repair at Northwestern Memorial Hospital between November 2011 and November 2013. Twenty-six patients who died within 9 months after surgery were excluded because of competing risks with the study end points. Demographics, medical history and medications, hospitalization and procedure-related factors, and postoperative complications were collected from the medical record. The primary end point was LTF 1 month after surgery (LTF1M), defined as lack of an in-person outpatient visit with a vascular surgeon 1 month after the index procedure. Secondary outcomes were LTF 1 year after surgery (LTF1Y), defined as lack of an in-person outpatient visit with a vascular surgeon between 9 and 22 months after discharge, and overall 5-year survival. RESULTS: Overall LTF1M and LTF1Y rates were 27.3% and 46.8%, respectively. Kaplan-Meier analysis revealed no difference in survival based on the LTF1M status (P = 0.72), but patients who were LTF1Y had significantly worse survival at 5 years (P < 0.001). Seeing a nonvascular surgeon specialist at our institution (odds ratio (OR) 0.58, 95% confidence interval (CI): 0.35-0.94, P = 0.03) and having a reintervention (OR 0.17, 95% CI: 0.08-0.37, P < 0.001) were associated with decreased LTF1Y in a multivariable model. Overall mortality was more likely with LTF1Y (hazard ratio (HR) 3.27, 95% CI: 1.86-5.76, P < 0.001) and less likely with seeing another specialist at our institution (HR 0.38, 95% CI: 0.20-0.75, P = 0.005). CONCLUSIONS: LTF rates after vascular surgery are high and associated with poor long-term outcomes. Patients who did not see a nonvascular surgeon specialist at our institution had higher rates of LTF1Y and worse overall mortality, suggesting that improved integration of care can improve LTF and survival.

Microbial Colonization of Germ-Free Mice Restores Neointimal Hyperplasia Development After Arterial Injury.

Background The potential role of the gut microbiome in cardiovascular diseases is increasingly evident. Arterial restenosis attributable to neointimal hyperplasia after cardiovascular procedures such as balloon angioplasty, stenting, and bypass surgery is a common cause of treatment failure, yet whether gut microbiota participate in the development of neointimal hyperplasia remains largely unknown. Methods and Results We performed fecal microbial transplantation from conventionally raised male C57BL/6 mice to age-, sex-, and strain-matched germ-free mice. Five weeks after inoculation, all mice underwent unilateral carotid ligation. Neointimal hyperplasia development was quantified after 4 weeks. Conventionally raised and germ-free cohorts served as comparison groups. Conclusions Germ-free mice have significantly attenuated neointimal hyperplasia development compared with conventionally raised mice. The arterial remodeling response is restored by fecal transplantation. Our results describe a causative role of gut microbiota in contributing to the pathogenesis of neointimal hyperplasia.

Microbiota composition modulates inflammation and neointimal hyperplasia after arterial angioplasty.

BACKGROUND: Neointimal hyperplasia is a major contributor to restenosis after arterial interventions, but the genetic and environmental mechanisms underlying the variable propensity for neointimal hyperplasia between individuals, including the role of commensal microbiota, are not well understood. We sought to characterize how shifting the microbiome using cage sharing and bedding mixing between rats with differing restenosis phenotypes after carotid artery balloon angioplasty could alter arterial remodeling. METHODS: We co-housed and mixed bedding between genetically distinct rats (Lewis [LE] and Sprague-Dawley [SD]) that harbor different commensal microbes and that are known to have different neointimal hyperplasia responses to carotid artery balloon angioplasty. Sequencing of the 16S ribosomal RNA gene was used to monitor changes in the gut microbiome. RESULTS: There were significant differences in neointimal hyperplasia between non-co-housed LE and SD rats 14 days after carotid artery angioplasty (mean intima + media [I + M] area, 0.117 ± 0.014 mm2 LE vs 0.275 ± 0.021 mm2 SD; P < .001) that were diminished by co-housing. Co-housing also altered local adventitial Ki67 immunoreactivity, local accumulation of leukocytes and macrophages (total and M2), and interleukin 17A concentration 3 days after surgery in each strain. Non-co-housed SD and LE rats had microbiomes distinguished by both weighted (P = .012) and unweighted (P < .001) UniFrac beta diversity distances, although without significant differences in alpha diversity. The difference in unweighted beta diversity between the fecal microbiota of SD and LE rats was significantly reduced by co-housing. Operational taxonomic units that significantly correlated with average I + M area include Parabacteroides distasonis, Desulfovibrio, Methanosphaera, Peptococcus, and Prevotella. Finally, serum concentrations of microbe-derived metabolites hydroxyanthranilic acid and kynurenine/tryptophan ratio were significantly associated with I + M area in both rat strains independent of co-housing. CONCLUSIONS: We describe a novel mechanism for how microbiome manipulations affect arterial remodeling and the inflammatory response after arterial injury. A greater understanding of the host inflammatory-microbe axis could uncover novel therapeutic targets for the prevention and treatment of restenosis.

Insights From a Short-Term Protein-Calorie Restriction Exploratory Trial in Elective Carotid Endarterectomy Patients.

BACKGROUND: Open vascular surgery interventions are not infrequently hampered by complication rates and durability. Preclinical surgical models show promising beneficial effects in modulating the host response to surgical injury via short-term dietary preconditioning. Here, we explore short-term protein-calorie restriction preconditioning in patients undergoing elective carotid endarterectomy to understand patient participation dynamics and practicalities of robust research approaches around nutritional/surgical interventions. METHODS: We designed a pilot prospective, multicenter, randomized controlled study in patients undergoing carotid endarterectomy. After a 3:2 randomization to a 3-day preoperative protein-calorie restriction regimen (30% calorie/70% protein restriction) or ad libitum group, blood, clinical parameters, and stool samples were collected at baseline, pre-op, and post-op days 1 and 30. Subcutaneous and perivascular adipose tissues were harvested periprocedurally. Samples were analyzed for standard chemistries and cell counts, adipokines. Bacterial DNA isolation and 16S rRNA sequencing were performed on stool samples and the relative abundance of bacterial species was measured. RESULTS: Fifty-one patients were screened, 9 patients consented to the study, 5 were randomized, and 4 completed the trial. The main reason for non-consent was a 3-day in-hospital stay. All 4 participants were randomized to the protein-calorie restriction group, underwent successful endarterectomy, reported no compliance difficulties, nor were there adverse events. Stool analysis trended toward increased abundance of the sulfide-producing bacterial species Bilophila wadsworthia after dietary intervention (P = .08). CONCLUSIONS: Although carotid endarterectomy patients held low enthusiasm for a 3-day preoperative inpatient stay, there were no adverse effects in this small cohort. Multidisciplinary longitudinal research processes were successfully executed throughout the nutritional/surgical intervention. Future translational endeavors into dietary preconditioning of vascular surgery patients should focus on outpatient approaches.

Peripheral artery reconstructions using cryopreserved arterial allografts in infected fields.

OBJECTIVE: Cryopreserved human arterial allografts are a recognized acceptable alternative for vascular reconstruction when other traditional conduits are either unavailable or contraindicated. We reviewed our experience using cryopreserved arterial allografts for peripheral artery reconstructions in contaminated and infected surgical fields. METHODS: A single-center, retrospective review was conducted of 57 patients who underwent a peripheral vascular reconstruction using a cryopreserved arterial allograft from January 2002 through July 2017. Indications for repair included removal of infected prosthetic bypass (n = 29), revascularizations in contaminated fields (n = 11), primary arterial repair in the setting of infection (n = 10), and infected vascular closure devices (n = 7). Aorta-based repairs were excluded. Demographics, index procedural details, postoperative complications, and conduit patency were analyzed. Primary end points included conduit-related mortality and graft failure as measured by reinfection, hemorrhage, or aneurysmal degeneration. Mean follow-up for the study is 27.8 months (range, 2-125 months). RESULTS: A total of 57 peripheral vascular reconstructions using cryopreserved arterial allografts were performed during the 15-year period. Among the 22 women and 35 men treated, the mean age was 61 years. The vascular beds involved included iliofemoral (n = 39), femoropopliteal or femoral-distal (n = 10), axillosubclavian or brachial (n = 2), mesenteric (n = 3), and carotid (n = 3) arteries. Adjunctive muscle flap coverage of the allograft conduit was performed in the majority of cases (61%; n = 35). The 30-day mortality was 9%; one death was directly related to conduit insertion. The 30-day conduit-related complication rate was 14% and included hemorrhage from the graft requiring return to the operating room (n = 4) and graft infection (n = 4). The late conduit-related complication rate was 15.8% and included graft infection (n = 1), graft thrombosis (n = 3), major amputation resulting from conduit failure (n = 1), pseudoaneurysm degeneration requiring repair (n = 2), graft hemorrhage (n = 1), and symptomatic graft stenosis (n = 1). CONCLUSIONS: A cryopreserved arterial allograft is a useful alternative conduit for peripheral vascular reconstruction in infected or contaminated surgical fields when other autologous or prosthetic conduits are either unavailable or contraindicated. In the immediate postoperative period, these repairs demonstrate acceptable resistance to graft failure and reinfection, particularly in conjunction with adjunctive rotational muscle flap coverage. Late conduit-related complications appear to be infrequent.