Imaging human macular pigments with visible light optical coherence tomography and superluminescent diodes.

We demonstrate superluminescent diodes (SLDs) for visible light optical coherence tomography (OCT) of the human retina. SLDs are less costly than supercontinuum sources and have lower intrinsic excess noise, enabling imaging closer to the shot noise limit. While single SLDs are not broadband, they provide power concentrated at specific wavelengths relevant to retinal function. As a new, to the best of our knowledge, application, we image human macular pigments (MPs), which are thought to both aid vision and protect against advanced age-related macular degeneration. Using the unique depth-resolved capabilities of OCT, we localize MPs in depth to Henle's fibers beneath the foveal pit in the living human retina. Our approach reduces the cost of visible light OCT to nearly that of near-infrared (NIR) OCT while also providing information about clinically relevant MPs which cannot be measured in the NIR.

Learning curve across 2000 thoracolumbar pedicle screw placements using O-arm navigation: technical difficulties and their solutions.

INTRODUCTION: Instrumentation using the intraoperative O-arm navigation technique appears safer than its predecessor techniques. However, only a handful of surgeons often used navigation during spinal surgeries. Too many operative glitches and unreliable navigation accuracy were the important reasons cited even by experienced surgeons for not using spinal navigation. We have studied the accuracy of pedicle screw placement during the learning curve and beyond it. We have also discussed in detail the intricacies of the technique and solutions to the difficulties encountered using spinal navigation. MATERIALS AND METHODS: A total of 2000 thoracolumbar pedicle screws have been placed in the 324 spine surgeries meeting the inclusion and exclusion criteria included in this retrospective study. We have divided 2000 pedicle screw placements into consecutive groups of 200 each. We have compared these groups for the accuracy of screw placement with the surgeon's experience. RESULTS: The accuracy of pedicle screw placement using the "in-versus-out" grading system in group 1 was 85.5% which significantly increased in group 2 to 93.5% (p-value: 0.0099), and thereafter, there was a nonsignificant increase in subsequent groups with the graph achieving the shape of a plateau. CONCLUSION: Surgeons should learn the correct principles of the technique of O-arm navigation to prevent the loss of accuracy and place pedicle screws with high accuracy. There is a learning curve of around 30-35 surgeries or 200 pedicle screw placements to acclimatize with the technique of O-arm navigation and learn its principles.

Use of chitosan wound dressing for the treatment of surgical site infection: a case report.

Surgical site infections (SSIs) are treated using topical antiseptics and systemic antibiotics, but some cases are unresponsive to such regimens. This case study reports the effective healing of an SSI by a chitosan wound dressing (MaxioCel; Axio Biosolutions Private Limited, India) in a 63-year-old female patient. The patient presented with an infected, hard-to-heal wound in the abdominal region, developed after a hernia surgery, and was initially treated with standard procedures. However, due to the continuous progression of infection, a highly absorbent, bioactive microfibre dressing was selected for the treatment and was continued for two months with alternate-day dressing changes. After 60 days of treatment, wound healing was observed, along with remission from the infection, as well as reduction in exudate level and pain. The use of chitosan wound dressing in management of hard-to-heal infected wounds provides efficient remission of SSI and a faster healing rate.

CNN-Based Classifier as an Offline Trigger for the CREDO Experiment.

Gamification is known to enhance users' participation in education and research projects that follow the citizen science paradigm. The Cosmic Ray Extremely Distributed Observatory (CREDO) experiment is designed for the large-scale study of various radiation forms that continuously reach the Earth from space, collectively known as cosmic rays. The CREDO Detector app relies on a network of involved users and is now working worldwide across phones and other CMOS sensor-equipped devices. To broaden the user base and activate current users, CREDO extensively uses the gamification solutions like the periodical Particle Hunters Competition. However, the adverse effect of gamification is that the number of artefacts, i.e., signals unrelated to cosmic ray detection or openly related to cheating, substantially increases. To tag the artefacts appearing in the CREDO database we propose the method based on machine learning. The approach involves training the Convolutional Neural Network (CNN) to recognise the morphological difference between signals and artefacts. As a result we obtain the CNN-based trigger which is able to mimic the signal vs. artefact assignments of human annotators as closely as possible. To enhance the method, the input image signal is adaptively thresholded and then transformed using Daubechies wavelets. In this exploratory study, we use wavelet transforms to amplify distinctive image features. As a result, we obtain a very good recognition ratio of almost 99% for both signal and artefacts. The proposed solution allows eliminating the manual supervision of the competition process.

Perioperative and 1-year transcarotid revascularization outcomes in symptomatic patients.

OBJECTIVE: Previously published results of carotid revascularization with both transfemoral stenting and endarterectomy have demonstrated inferior perioperative stroke and death outcomes in neurologically symptomatic patients compared with those without symptoms. This study was completed to establish the real-world, symptom-based perioperative and follow-up outcomes for transcarotid artery revascularization (TCAR). METHODS: An institutional retrospective review of all TCARs performed outside of clinical trial regulations from 2016 to 2019 was completed. Eligible patients were classified as symptomatic or not based on a history of a unilateral neurologic deficit attributable to an extracranial carotid artery lesion within the previous 180 days. Univariate analysis consisting of Fisher's exact and Student t-tests, as appropriate, were performed between cohorts. Kaplan-Meier analysis was completed to estimate the stroke-free survival at 1 year postoperatively. RESULTS: Within the investigational period, 167 patients (85 symptomatic) qualified for study inclusion. Baseline demographics were roughly equivalent, although symptomatic patients were more likely to be female (28.0% vs 9.4%; P < .01). Procedures in symptomatic patients were associated with higher estimated blood loss (41 mL vs 58 mL; P = .04) and operative time (67 minutes vs 75 minutes; P = .06). We did not find an increased incidence of macroscopic debris in the filter of symptomatic patients after stent deployment. For symptomatic patients, we observed a perioperative (30-day) ipsilateral stroke risk of 1.2% (vs 2.4% in asymptomatic patients; P > .99), a myocardial infarction risk of 0% (vs 0%; P > .99), and a mortality risk of 4.9% (vs 0%; P = .06). Most deaths occurred after procedure-related discharge; as such, in-hospital (from index TCAR) mortality in symptomatic patients was 1.2%. The four perioperative deaths observed in our population were secondary to hemorrhagic stroke, acute on chronic congestive heart failure (n = 2), and unknown causes in the last patient. At 1 year after the procedure, 114 patients (54 symptomatic) had available data. In addition to the perioperative risks, in symptomatic patients we observed a rate of reintervention of 0% (vs 0%; P > .99), ipsilateral stroke of 3.7% (vs 0%; P = .22), >50% in-stent restenosis of 1.9% (vs 0%; P = .47), stent thrombosis of 3.7% (vs 0%; P = .22), and all-cause mortality of 13.0% (vs 10.0%; P = .77). Last, no difference was noted with respect to the 1-year stroke-free survival (P = .17) by Kaplan-Meier estimates. CONCLUSIONS: In this institutional series of patients undergoing TCAR, we found that symptomatic patients have a similar perioperative risk of stroke and myocardial infarction as asymptomatic patients. However, we did observe a strong statistical trend suggesting a higher mortality risk in symptomatic patients. There was no difference between cohorts with respect to 1-year stroke-free survival.

Perioperative and Long-term Results of Zenith Fenestrated Aortic Repair in Women.

BACKGROUND: Inferior perioperative outcomes for women receiving major vascular surgery are well established in the literature in multiple arterial distributions. Therefore, this study was completed to determine the perioperative and durability results associated with women undergoing complex aortic reconstruction using the Zenith Fenestrated platform (ZFEN; Cook Medical, Bloomington, IN). METHODS: A retrospective review of a fenestrated endovascular aortic repair (FEVAR) database capturing all ZFENs performed at our institution between October 2012 and March 2019 was completed. Preoperative, intraoperative, perioperative, and follow-up outcomes were tabulated for females and compared with their male counterparts. RESULTS: Within our study period, 136 total ZFEN procedures were performed; of which, 20 devices (14.7%) were implanted in women. Intraoperatively, we observed a higher rate of estimated blood loss (660.0 mL vs. 311.6 mL, P < 0.01) and resultant need for transfusion (1.4 vs. 0.3 units, P < 0.01) in women despite a similar frequency of brachial (5.0% vs. 7.8%, P > 0.99) and femoral artery cutdowns (55.0% vs. 49.1%, P = 0.81). Operative (295.7 min vs. 215.7 mins, P < 0.01) and fluoroscopy (84.3 vs. 58.7 min, P < 0.01) times were also significantly higher in females than those in their male counterparts. In the perioperative (30-day) period, we observed significantly longer length of stay (5.6 days vs. 3.3 days, P = 0.03) and continued need for transfusion (50% vs. 9.5%, P < 0.01) in women. Statistical trends favoring men were also noted with respect to all-cause mortality, reintervention, visceral stent thrombosis, renal failure, acute kidney injury, and respiratory failure. After a mean follow-up of nearly 2 years, we found no differences in late all-cause or aneurysm-related mortality, major adverse cardiovascular events, or need for reinterventions. CONCLUSIONS: The implantation of ZFEN in females is significantly more difficult than that in their male counterparts and may result in increased perioperative, but not necessarily long-term, complications.

Reputation offsets trust judgments based on social biases among Airbnb users.

To provide social exchange on a global level, sharing-economy companies leverage interpersonal trust between their members on a scale unimaginable even a few years ago. A challenge to this mission is the presence of social biases among a large heterogeneous and independent population of users, a factor that hinders the growth of these services. We investigate whether and to what extent a sharing-economy platform can design artificially engineered features, such as reputation systems, to override people's natural tendency to base judgments of trustworthiness on social biases. We focus on the common tendency to trust others who are similar (i.e., homophily) as a source of bias. We test this argument through an online experiment with 8,906 users of Airbnb, a leading hospitality company in the sharing economy. The experiment is based on an interpersonal investment game, in which we vary the characteristics of recipients to study trust through the interplay between homophily and reputation. Our findings show that reputation systems can significantly increase the trust between dissimilar users and that risk aversion has an inverse relationship with trust given high reputation. We also present evidence that our experimental findings are confirmed by analyses of 1 million actual hospitality interactions among users of Airbnb.

Subthalamic stimulation for cervical dystonia.

The globus pallidus internus (GPi) has been the primary target for deep brain stimulation (DBS) to treat severe medication-refractory dystonia. Some patients with primary cervical dystonia do not respond adequately to GPi stimulation. Subthalamic nucleus (STN) DBS may provide an alternative choice for treating this dystonia. In this study, we analysed the effect of bilateral STN DBS on two patients of medically refractory primary cervical dystonia. The severity of the dystonia was measured using the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) preoperatively, and 1, 3, 6 and 12 months postoperatively and yearly follow-up was performed. Any change in mental status was recorded using the Mini-Mental State Examination (MMSE) score. Surgery was performed using the Leksell stereotactic system and by fusing CT scan and MR images with neuronavigation and microelectrode recording. Both patients were followed for more than 3 years. STN DBS was well-tolerated by both patients with no adverse effects. The benefit seems to be immediate. The first patient showed 74% improvement, and the second patient showed 84.3% improvement in the overall TWSTRS score. No mental deterioration was observed in either of the cases, as the MMSE score remained unchanged in both patients. A prior bilateral pallidal lesion in the first case did not adversely affect the outcome. This study showed that bilateral STN DBS results in a very significant improvement in cervical dystonia with no mental worsening and suggests that STN DBS may be an alternative to GPi DBS for treating primary cervical dystonia.

Outcomes associated with a transcarotid artery revascularization-centered protocol in high-risk carotid revascularizations using the ENROUTE neuroprotection system.

OBJECTIVE: This investigation describes the perioperative and early follow-up results associated with transcarotid artery revascularization (TCAR) in patients not participating in the Safety and Efficacy Study for Reverse Flow Used During Carotid Artery Stenting Procedure II (ROADSTER-2) registry using the ENROUTE neuroprotection system (ENPS; Silk Road Medical, Sunnyvale, Calif). METHODS: A retrospective review was performed capturing all TCAR/ENPS procedures in patients deemed to be at high risk for complications after traditional carotid endarterectomy. All patients enrolled in the ROADSTER-2 registry were excluded, leaving only those treated outside trial regulations for analysis. Preoperative demographics, intraoperative variables, and perioperative and follow-up outcomes were abstracted and reported herein. RESULTS: From December 2015 to January 2018, there were 75 carotid arteries treated at our institution. All interventions were performed on carotid arteries that were symptomatic with ≥50% stenosis (46.7%) or asymptomatic with ≥80% stenosis (53.3%) by duplex ultrasound and computed tomography angiography. Technical success in our series was 97.3% (73/75), with treatment failures attributed to one case of common carotid artery dissection and another secondary to stent maldeployment in the external carotid artery. Perioperative (30-day) ipsilateral stroke rate was 2.7% (n = 2), myocardial infarction incidence was 0%, and mortality rate was 2.7% (n = 2). We did not observe any cranial nerve injuries. After a mean follow-up of 8.0 ± 6.7 months, no carotid stents required reintervention. However, we noted one instance of minor (<50%) in-stent stenosis and one asymptomatic stent thrombosis. One additional ipsilateral stroke was observed on follow-up, probably from a cardiac source. CONCLUSIONS: We report that dynamic reverse-flow TCAR using the ENPS continues to be safe, feasible, and efficacious with minimal risks of postoperative stroke, myocardial infarction, and mortality outside of ROADSTER-2 regulations.

Fenestrated endovascular aneurysm repair-induced acute kidney injury does not result in chronic renal dysfunction.

OBJECTIVE: Acute kidney injury (AKI) is a common physiologic complication after fenestrated endovascular aneurysm repair (FEVAR). This investigation was initiated to determine the unknown impact of post-FEVAR AKI on long-term renal function after index hospital discharge. METHODS: A retrospective review was performed of an institutional FEVAR database capturing preoperative, intraoperative, and postoperative variables related to the implantation of consecutive Zenith Fenestrated endografts (ZFEN; Cook Medical, Bloomington, Ind) between October 2012 and April 2018. AKI in this study was bimodally defined as qualification by either Risk, Injury, Failure, Loss of kidney function, and End-stage (RIFLE) criteria or a postoperative serum creatinine (sCr) concentration increase of 0.5 mg/dL from baseline. Glomerular filtration rate (GFR) was calculated using the validated Modification of Diet in Renal Disease (MDRD) study equation. RESULTS: During the study period, 120 FEVARs were performed at our institution. Twenty-four (20%) patients exhibited postoperative AKI by our established definitions. Two in-hospital deaths occurred in the AKI cohort compared with none in the remaining FEVARs (P = .04). Four (16.7%) AKI patients required perioperative (<30-day) renal replacement therapy, three of whom were successfully weaned before discharge. FEVARs uncomplicated by AKI exhibited no differences in sCr concentration from baseline to 1-month, 6-month, 1-year, and 2-year follow-up (mean, 1.8 ± 1.4 years). In contrast, patients exhibiting AKI experienced an sCr concentration increase of 57.1% (P = .01) at 1 month after the procedure. This elevation decreased to 14.3% (P = .35) at 6 months after the procedure and was maintained at baseline values at 1- and 2-year office visits (follow-up, 1.3 ± 1.5 years). A similar pattern of gradual recovery during follow-up was also observed with respect to calculated GFR. CONCLUSIONS: AKI is common after FEVAR but rarely results in permanent renal dysfunction as both sCr concentration and GFR return to baseline by 6 months after the procedure.

Nitrate nutrition influences multiple factors in order to increase energy efficiency under hypoxia in Arabidopsis.

BACKGROUND AND AIMS: Nitrogen (N) levels vary between ecosystems, while the form of available N has a substantial impact on growth, development and perception of stress. Plants have the capacity to assimilate N in the form of either nitrate (NO3-) or ammonium (NH4+). Recent studies revealed that NO3- nutrition increases nitric oxide (NO) levels under hypoxia. When oxygen availability changes, plants need to generate energy to protect themselves against hypoxia-induced damage. As the effects of NO3- or NH4+ nutrition on energy production remain unresolved, this study was conducted to investigate the role of N source on group VII transcription factors, fermentative genes, energy metabolism and respiration under normoxic and hypoxic conditions. METHODS: We used Arabidopsis plants grown on Hoagland medium with either NO3- or NH4+ as a source of N and exposed to 0.8 % oxygen environment. In both roots and seedlings, we investigated the phytoglobin-nitric oxide cycle and the pathways of fermentation and respiration; furthermore, NO levels were tested using a combination of techniques including diaminofluorescein fluorescence, the gas phase Griess reagent assay, respiration by using an oxygen sensor and gene expression analysis by real-time quantitative reverse transcription-PCR methods. KEY RESULTS: Under NO3- nutrition, hypoxic stress leads to increases in nitrate reductase activity, NO production, class 1 phytoglobin transcript abundance and metphytoglobin reductase activity. In contrast, none of these processes responded to hypoxia under NH4+ nutrition. Under NO3- nutrition, a decreased total respiratory rate and increased alternative oxidase capacity and expression were observed during hypoxia. Data correlated with decreased reactive oxygen species and lipid peroxidation levels. Moreover, increased fermentation and NAD+ recycling as well as increased ATP production concomitant with the increased expression of transcription factor genes HRE1, HRE2, RAP2.2 and RAP2.12 were observed during hypoxia under NO3- nutrition. CONCLUSIONS: The results of this study collectively indicate that nitrate nutrition influences multiple factors in order to increase energy efficiency under hypoxia.

Aggressive Surveillance Is Needed to Detect Endoleaks and Junctional Separation between Device Components after Zenith Fenestrated Aortic Reconstruction.

BACKGROUND: Junctional separation and resulting type IIIa endoleak is a well-known problem after EVAR (endovascular aneurysm repair). This complication results in sac pressurization, enlargement, and eventual rupture. In this manuscript, we review the incidence of this late finding in our experience with the Cook Zenith fenestrated endoprosthesis (ZFEN, Bloomington, IN). METHODS: A retrospective review was performed of a prospectively maintained institutional ZFEN fenestrated EVAR database capturing all ZFENs implanted at a large-volume, academic hospital system. Patients who experienced junctional separation between the fenestrated main body and distal bifurcated graft (with or without type IIIa endoleak) at any time after initial endoprosthesis implantation were subject to further evaluation of imaging and medical records to abstract clinical courses. RESULTS: In 110 ZFENs implanted from October 2012 to December 2017 followed for a mean of 1.5 years, we observed a 4.5% and 2.7% incidence of clinically significant junctional separation and type IIIa endoleak, respectively. Junctional separation was directly related to concurrent type Ib endoleak in all 5 patients. Three patients presented with sac enlargement. One patient did not demonstrate any evidence of clinically significant endoleak and had a decreasing sac size during follow-up imaging. The mean time to diagnosis of modular separation in these patients was 40 months. Junctional separation was captured in surveillance in 2 patients and reintervened upon before manifestation of endoleak. However, the remaining 3 patients completed modular separation resulting in rupture and emergent intervention in 2 and an aortic-related mortality in the other. CONCLUSIONS: Junctional separation between the fenestrated main and distal bifurcated body with the potential for type IIIa endoleak is an established complication associated with the ZFEN platform. Therefore, we advocate for maximizing aortic overlap during the index procedure followed by aggressive surveillance and treatment of stent overlap loss captured on imaging.

Osteopontin may be a driver of abdominal aortic aneurysm formation.

OBJECTIVE: Previous in vitro and animal studies have suggested that osteopontin (OPN), an inflammatory extracellular matrix protein, is involved in the formation and growth of abdominal aortic aneurysms (AAAs). However, the mechanism by which this occurs continues to be nebulous. The relationship between OPN and inflammation-suppressing lymphocytes present in the human AAA condition was investigated and presented herein. METHODS: Serum OPN concentrations were measured in healthy, risk factor-matched non-AAA and AAA patients by enzyme-linked immunosorbent assay (ELISA). Immunohistochemistry was used to determine the source of OPN secretion using aortic tissue collected from multiorgan donors and AAA patients undergoing open surgical repair. Vascular smooth muscle cells (VSMCs) were exposed to various inflammatory mediators, and OPN expression was evaluated by quantitative reverse transcriptase-polymerase chain reaction and ELISA. The inflammatory nature of OPN and the aortic wall was determined using a TR1 suppressor cell induction assay as a surrogate and characterized by ELISA and fluorescence-activated cell sorting. RESULTS: OPN was found to be elevated in both the plasma and aortic homogenate of AAA patients compared with controls. On immunohistochemistry, OPN localized to the tunica media of the diseased aorta but was minimally expressed in healthy aorta. In vitro, cigarette smoke extract was the most potent stimulator of OPN secretion by VSMCs and increased both messenger RNA and supernatant concentrations. OPN demonstrated an ability to inhibit the induction of interleukin 10-secreting TR1 lymphocytes, a depleted population in the AAA patient, from naive precursors. Last, neutralizing receptor targets of OPN in the setting of AAA homogenate coincubation abrogated the inhibition of TR1 induction. CONCLUSIONS: OPN, secreted by the VSMCs of the tunica media, is elevated in the circulating plasma and aortic wall of patients with AAA. It can inhibit the induction of the TR1 suppressor cell, leading to an overall proinflammatory state contributing to progressive aortic wall breakdown and dilation.

Institutional experience with the Zenith Fenestrated aortic stent graft.

OBJECTIVE: The Zenith Fenestrated (ZFEN; Cook Medical, Bloomington, Ind) aortic stent graft system was approved for commercial use by the Food and Drug Administration in April 2012. We report our single-center experience of 100 consecutive patients treated with the ZFEN platform from October 2012 to March 2017. METHODS: A retrospective review of our prospectively maintained fenestrated endovascular aneurysm repair (FEVAR) database at a tertiary care academic institution located in the Midwest United States was performed for descriptive analysis. All continuous variables are reported as a mean ± standard deviation and compared using two-sided Student t-tests. Categorical variables were compared using two-sided Fisher exact tests. RESULTS: All but one of the procedures were elective in nature. Overall intraoperative characteristics included a mean blood loss (estimated blood loss) of 388 ± 385 mL, fluoroscopy time of 63 ± 30 minutes, radiation dose of 437 ± 272 rad, contrast material volume of 99 ± 36 mL, and operative time of 236 ± 87 minutes. Average number of visceral arteries stented was 2.1 ± 0.5. Technical success was achieved in 98% of the patients. Statistically significant (P < .05) improvement in estimated blood loss (2.1-fold) was observed in the second half of our series. Interestingly, no improvements were made in terms of fluoroscopy time, radiation exposure, contrast material use, or operative time. However, procedural difficulty increased in the last half by number of visceral arteries stented as a surrogate (1.9 vs 2.2; P < .05). Mean length of stay was 3.6 ± 4.3 days. Perioperative mortality at 30 days was 2%. Perioperative morbidity included a 5% incidence of any bowel ischemia, 1% of spinal cord ischemia, 3% of renal failure requiring hemodialysis, 1% of stroke, and 4% of myocardial infarction. Average follow-up was 1.7 ± 1.4 years. Reintervention during the follow-up phase was 20%. Of the 209 visceral arteries stented, we noted 6 instances of stent thrombosis, 6 of kinking or stenosis, and 1 of stent fracture in follow-up. Endoleak, most commonly type II, was present or could not be excluded in 15% of all FEVARs at last available computed tomography angiography. CONCLUSIONS: In our experience, FEVAR with the ZFEN system continues to be safe and effective. There is a significant rate of reintervention observed, and close monitoring is fundamental to maintaining good clinical results.

Adjunctive visceral artery chimney in patients undergoing Zenith Fenestrated aortic repair.

OBJECTIVE: Visceral artery chimneys have been employed as an adjunct to endovascular aneurysm repair (EVAR) to treat short-neck infrarenal and juxtarenal aortic aneurysms for more than two decades. With the widespread introduction of fenestrated endovascular aneurysm repair by the Food and Drug Administration-approved Zenith Fenestrated endograft (ZFEN; Cook Medical, Bloomington, Ind) to the United States in 2012, clinicians gained the ability to apply the chimney technique to these custom devices for difficult anatomy. The purpose of this report was to demonstrate feasibility and to provide evidence on the performance of chimneys for the treatment of complex juxtarenal aneurysms that could not be adequately treated with ZFEN alone. METHODS: A retrospective analysis was performed of a prospectively maintained institutional ZFEN database capturing 110 fenestrated endovascular aneurysm repairs from October 2012 to January 2018 to identify patients undergoing a concomitant visceral artery chimney. All patients with <12 months of follow-up were excluded from further analysis. Demographic, anatomic, intraoperative, perioperative, and follow-up characteristics were tabulated and analyzed. RESULTS: Six patients met criteria and were included in this investigation. They were universally male with a mean age of 76.2 years at the time of ZFEN/chimney. Chimneys were placed in a total of six visceral arteries (n = 1 per patient) consisting of three renal arteries, two celiac arteries, and one accessory renal artery. Mean estimated blood loss and operative time were 283 mL and 298 minutes, respectively. Technical success was achieved in all cases. Two small type IA "gutter" endoleaks were detected early; both spontaneously resolved on follow-up. We observed no instances of chimney migration, stenosis, or thrombosis perioperatively or on follow-up. Two reinterventions were performed in these six patients; these consisted of a repeated renal stent for ostial stenosis at a main body fenestration and a common femoral artery endarterectomy and patch angioplasty for an access-related common femoral artery occlusion. CONCLUSIONS: Use of ZFEN in conjunction with a singular chimney is safe, feasible, and durable in patients with difficult anatomy who do not meet instructions for use as demonstrated in this limited series.

Ethnic minorities with critical limb ischemia derive equal amputation risk reduction from autologous cell therapy compared with whites.

OBJECTIVE: Ethnic minorities (nonwhites) with critical limb ischemia (CLI) have historically performed worse compared with whites with regard to major amputation risk reduction and amputation-free survival (AFS) after peripheral vascular intervention. This post hoc analysis was completed to determine whether this precedent also extended to treatment of CLI without a suitable revascularization option with intramuscular injections of concentrated bone marrow aspirate (cBMA). METHODS: The treatment arm of the randomized, double-blind, multicenter MarrowStim PAD Kit for the Treatment of Critical Limb Ischemia in Subjects with Severe Peripheral Arterial Disease (MOBILE) trial was stratified by ethnicity and evaluated for demographics, comorbidities, and outcomes. The primary and therapeutic end point was 1-year AFS and major amputation, respectively. Noninferiority analysis was performed with the margin set at historically reported hazard ratios. RESULTS: Thirty-seven minority (African American, Hispanic, other) CLI patients (9 placebo, 28 cBMA) with no suitable revascularization option were randomized to cBMA or placebo at a 3:1 ratio during the MOBILE trial. At 1-year follow-up for the treatment group, overall AFS was 80%. Of the 28 minority patients randomized to cBMA intervention, an 89% AFS rate was observed compared with 77% in whites. Specifically, 22 of 24 (92%) African Americans survived amputation free at 1-year follow-up. Noninferiority testing confirmed no difference between whites and the ethnic minority treated with cBMA with respect to major amputation reduction; however, noninferiority could not be confirmed with regard to AFS. No significant differences favoring whites treated with cBMA were noted in the secondary end points of vascular quality of life, limb pain, ankle-brachial index, toe-brachial index, transcutaneous oximetry, and 6-minute walk testing. CONCLUSIONS: This post hoc analysis of the MOBILE trial demonstrates noninferiority of cBMA intervention in minorities with no-option CLI for the therapeutic end point of major amputation prevention. cBMA represents a novel treatment paradigm and should be explored for minorities with poor revascularization options who face impending amputation secondary to progressive CLI.

Metformin does not reduce inflammation in diabetics with abdominal aortic aneurysm or at high risk of abdominal aortic aneurysm formation.

INTRODUCTION: The protective effect of diabetes mellitus on abdominal aortic aneurysm formation and growth has been repeatedly observed in population studies but continues to be poorly understood. However, recent investigations have suggested that metformin, a staple antihyperglycemic medication, may be independently protective against abdominal aortic aneurysm formation and growth. Therefore, we describe the effect of metformin in abdominal aortic aneurysm and at-risk patients on markers of inflammation, the driver of early abdominal aortic aneurysm formation and growth. METHODS: Peripheral blood was collected from patients previously diagnosed with abdominal aortic aneurysm or presenting for their U.S. Preventive Task Force-recommended abdominal aortic aneurysm screening. Plasma and circulating peripheral blood mononuclear cells were isolated using Ficoll density centrifugation. Circulating plasma inflammatory and regulatory cytokines were assessed with enzyme-linked immunosorbent assays. CD4+ cell phenotyping was performed using flow cytometric analysis and expressed as a proportion of total CD4+ cells. To determine the circulating antibody to self-antigen response, a modified enzyme-linked immunosorbent assay was performed against antibodies to collagen type V and elastin fragments. RESULTS: Peripheral blood was isolated from 266 patients without diabetes mellitus ( n=182), with diabetes mellitus not treated with metformin ( n=34), and with diabetes mellitus actively taking metformin ( n=50) from 2015 to 2017. We found no differences in the expression of Tr1, Th17, and Treg CD4+ fractions within diabetics ± metformin. When comparing inflammatory cytokines, we detected no differences in IL-1ß, IL-6, IL-17, IL-23, IFN-γ, and TNF-α. Conversely, no differences were observed pertaining to the expression to regulatory cytokines IL-4, IL-10, IL-13, TSG-6, or TGF-ß. Lastly, no differences in expression of collagen type V and elastin fragment antigen and/or antibodies were detected with metformin use in diabetics. CONCLUSION: Metformin in diabetics at-risk for abdominal aortic aneurysm or diagnosed with abdominal aortic aneurysm does not seem to alter the peripheral inflammatory environment.

Safety and efficacy of rivaroxaban compared with warfarin in patients undergoing peripheral arterial procedures.

OBJECTIVE: Rivaroxaban is a United States Food and Drug Administration-approved oral anticoagulant for venous thromboembolic disease; however, there is no information regarding the safety and its efficacy to support its use in patients after open or endovascular arterial interventions. We report the safety and efficacy of rivaroxaban vs warfarin in patients undergoing peripheral arterial interventions. METHODS: This single-institution retrospective study analyzed all sequential patients from December 2012 to August 2014 (21 months) who were prescribed rivaroxaban or warfarin after a peripheral arterial procedure. Our study population was then compared using American College of Chest Physicians guidelines with patients then stratified as low, medium, or high risk for bleeding complications. Statistical analyses were performed using the Student t-test and χ2 test to compare demographics, readmissions because of bleeding, and the need for secondary interventions. Logistic regression models were used for analysis of variables associated with bleeding complications and secondary interventions. The Fisher exact test was used for power analysis. RESULTS: There were 44 patients in the rivaroxaban group and 50 patients in the warfarin group. Differences between demographics and risk factors for bleeding between groups or reintervention rate were not statistically significant (P = .297). However, subgroup evaluation of the safety profile suggests that patients who were aged ≤65 years and on warfarin had an overall higher incidence of major bleeding (P = .020). Patients who were aged >65 years, undergoing open operation, had a significant risk for reintervention (P = .047) when they received rivaroxaban. CONCLUSIONS: Real-world experience using rivaroxaban and warfarin in patients after peripheral arterial procedures suggests a comparable safety and efficacy profile. Subgroup analysis of those requiring an open operation demonstrated a decreased bleeding risk when rivaroxaban was used (in those aged <65 years) but an increased risk for secondary interventions. Further studies with a larger cohort are required to validate our results.