A population of dust-enshrouded objects orbiting the Galactic black hole.

The central 0.1 parsecs of the Milky Way host a supermassive black hole identified with the position of the radio and infrared source Sagittarius A* (refs. 1,2), a cluster of young, massive stars (the S stars3) and various gaseous features4,5. Recently, two unusual objects have been found to be closely orbiting Sagittarius A*: the so-called G sources, G1 and G2. These objects are unresolved (having a size of the order of 100 astronomical units, except at periapse, where the tidal interaction with the black hole stretches them along the orbit) and they show both thermal dust emission and line emission from ionized gas6-10. G1 and G2 have generated attention because they appear to be tidally interacting with the supermassive Galactic black hole, possibly enhancing its accretion activity. No broad consensus has yet been reached concerning their nature: the G objects show the characteristics of gas and dust clouds but display the dynamical properties of stellar-mass objects. Here we report observations of four additional G objects, all lying within 0.04 parsecs of the black hole and forming a class that is probably unique to this environment. The widely varying orbits derived for the six G objects demonstrate that they were commonly but separately formed.

Decreasing prevalence of centers meeting the Society for Vascular Surgery abdominal aortic aneurysm guidelines in the United States.

OBJECTIVE: Based on data supporting a volume-outcome relationship in elective aortic aneurysm repair, the Society of Vascular Surgery (SVS) guidelines recommend that endovascular aortic repair (EVAR) be localized to centers that perform ≥10 operations annually and have a perioperative mortality and conversion-to-open rate of ≤2% and that open aortic repair (OAR) be localized to centers that perform ≥10 open aortic operations annually and have a perioperative mortality ≤5%. However, the number and distribution of centers meeting the SVS criteria remains unclear. This study aimed to estimate the temporal trends and geographic distribution of Centers Meeting the SVS Aortic Guidelines (CMAG) in the United States. METHODS: The SVS Vascular Quality Initiative was queried for all OAR, aortic bypasses, and EVAR from 2011 to 2019. Annual OAR and EVAR volume, 30-day elective operative mortality for OAR or EVAR, and EVAR conversion-to-open rate for all centers were calculated. The SVS guidelines for OAR and EVAR, individually and combined, were applied to each institution leading to a CMAG designation. The proportion of CMAGs by region (West, Midwest, South, and Northeast) were compared by year using a χ2 test. Temporal trends were estimated using a multivariable logistic regression for CMAG, adjusting by region. RESULTS: Overall, 67,865 patients (49,264 EVAR; 11,010 OAR; 7591 aortic bypasses) at 336 institutions were examined. The proportion of EVAR CMAGs increased nationally by 1.7% annually from 51.6% (n = 33/64) in 2011 to 67.1% (n = 190/283) in 2019 (ß = .05; 95% confidence interval [CI], 0.01-0.09; P = .02). The proportion of EVAR CMAGs across regions ranged from 27.3% to 66.7% in 2011 to 63.9% to 72.9% in 2019. In contrast, the proportion of OAR CMAGs has decreased nationally by 1.8% annually from 32.8% (n = 21/64) in 2011 to 16.3% (n = 46/283) in 2019 (ß = -.14; 95% CI, -0.19 to -0.10; P < .01). Combined EVAR and OAR CMAGs were even less frequent and decreased by 1.5% annually from 26.6% (n = 17/64) in 2011 to 13.1% (n = 37/283) in 2019 (ß = -.12; 95% CI, -0.17 to -0.07; P < .01). In 2019, there was no significant difference in regional variation of the proportion of combined EVAR and OAR CMAGs (P = .82). CONCLUSIONS: Although an increasing proportion of institutions nationally meet the SVS guidelines for EVAR, a smaller proportion meet them for OAR, with a concerning downward trend. These data question whether we can safely offer OAR at most institutions, have important implications about sufficient OAR exposure for trainees, and support regionalization of OAR.

Call to action: Blueprint for change in acute and critical care nursing.

Herein, we propose a blueprint for action to completely measure and recognize the care provided by acute and critical care nurses to be incorporated into policy that shapes and supports practice. We address the nature of nurses' work by identifying nine practice domains, hospital practice environment assumptions, and expected outcomes. Nurses' work, as a cross-system process, needs to be included in hospital-based core measures to fully reflect nurses' impact on patient care. We call for a balanced measurement portfolio focused on patient/family-, unit-, and systems-level outcomes. We focus on what nurses do and what patients and their families can expect rather than only on the elimination of select adverse events. We provide a way forward to allow measure development and implementation with incentives for their use. This approach to making nurses' contributions and impact on outcomes visible will enhance acute and critical care nursing practice and benefit patients and their families.

The Nonmonotonic Dose Dependence of Protein Expression in Cells Transfected with Self-Amplifying RNA.

Self-amplifying (sa) RNA molecules-"replicons"-derived from the genomes of positive-sense RNA viruses are receiving increasing attention as gene and vaccine delivery vehicles. This is because mRNA forms of genes of interest can be incorporated into them and strongly amplified, thereby enhancing target protein expression. In this report, we demonstrate a nonmonotonic dependence of protein expression on the mass of transfected replicon, in contrast to the usual, monotonic case of non-saRNA transfections. We lipotransfected a variety of cell lines with increasing masses of enhanced yellow fluorescent protein (eYFP) as a reporter gene in sa form and found that there is a "sweet spot" at which protein expression and cell viability are optimum. To control the varying mass of transfected replicon RNA for a given mass of Lipofectamine, the replicons were mixed with a "carrier" RNA that is neither replicated nor translated; the total mass of transfected RNA was kept constant while increasing the fraction of the replicon from zero to one. Fluorescence microscopy studies showed that the optimum protein expression and cell viability are achieved for replicon fractions as small as 1/10 of the total transfected RNA, and these results were quantified by a systematic series of flow cytometry measurements. IMPORTANCE Positive-sense RNA viruses often have a cytotoxic effect on their host cell because of the strength of their RNA replicase proteins, even though only one copy of their genome begins the viral life cycle in each cell. Noninfectious forms of them-replicons-which include just their RNA replication-related genes, are also strongly self-amplifying and cytotoxic. Accordingly, when replicons fused with nonviral genes of interest are transfected into cells to amplify expression of proteins of interest, one needs to keep the replicon "dose" sufficiently low. We demonstrate how to control the number of RNA replicons getting into transfected cells and that there is a sweet spot for the replicon dose that optimizes protein expression and cell viability. Examples are given for the case of Nodamura viral replicons with fluorescent protein reporter genes in a variety of mammalian cell lines, quantified by flow cytometry and live/dead cell assays.

Socioeconomic status fails to account for worse outcomes in non-Hispanic black patients undergoing carotid revascularization.

OBJECTIVE: Previous studies have reported an association of Black race with worse carotid revascularization outcomes, but rarely include socioeconomic status as a confounding covariate. We aimed to assess the association of race and ethnicity with in-hospital and long-term outcomes following carotid revascularization before and after accounting for socioeconomic status. METHODS: We identified non-Hispanic Black and non-Hispanic white patients who underwent carotid endarterectomy, transfemoral carotid stenting, or transcarotid artery revascularization between 2003 and 2022 in the Vascular Quality Initiative. Primary outcomes were in-hospital stroke/death and long-term stroke/death. Multivariable logistic regression and Cox proportional hazards models were used to assess the association of race with perioperative and long-term outcomes after adjusting for baseline characteristics using a sequential model approach without and with consideration of Area Deprivation Index (ADI), a validated composite marker of socioeconomic status. RESULTS: Of 201,395 patients, 5.1% (n = 10,195) were non-Hispanic Black, and 94.9% (n = 191,200) were non-Hispanic white. Mean follow-up time was 3.4±0.01 years. A disproportionately high percentage of Black patients were living in more socioeconomically deprived neighborhoods relative to their white counterparts (67.5% vs 54.2%; P < .001). After adjusting for demographic, comorbidity, and disease characteristics, Black race was associated with greater odds of in-hospital (adjusted odds ratio [aOR], 1.24; 95% confidence interval [CI], 1.10-1.40) and long-term stroke/death (adjusted hazard ratio [aHR], 1.13; 95% CI, 1.04-1.23). These associations did not substantially change after additionally adjusting for ADI; Black race was persistently associated with greater odds of in-hospital (aOR, 1.23; 95% CI, 1.09-1.39) and long-term stroke/death (aHR, 1.12; 95% CI, 1.03-1.21). Patients living in the most deprived neighborhoods were at greater risk of long-term stroke/death compared with patients living in the least deprived neighborhoods (aHR, 1.19; 95% CI, 1.05-1.35). CONCLUSIONS: Non-Hispanic Black race is associated with worse in-hospital and long-term outcomes following carotid revascularization despite accounting for neighborhood socioeconomic deprivation. There appears to be unrecognized gaps in care that prevent Black patients from experiencing equitable outcomes following carotid artery revascularization.

Transcarotid artery revascularization is associated with similar outcomes to carotid endarterectomy regardless of patient risk status.

BACKGROUND: Carotid artery stenting (CAS), including both transfemoral carotid artery stenting (TFCAS) and transcarotid artery revascularization (TCAR), reimbursement has been limited to high-risk patients by the Centers for Medicare & Medicaid Services (CMS) since 2005. We aimed to assess the association of CMS high-risk status with perioperative outcomes for carotid endarterectomy (CEA), TFCAS, and TCAR. METHODS: We performed a retrospective review of all Vascular Quality Initiative patients who underwent carotid revascularization between 2015 and 2020. Patients were stratified by whether they met CMS CAS criteria, and univariable and multivariable logistic regression analyses were performed to assess the association of procedure type (CEA, TFCAS, TCAR) with perioperative outcomes. RESULTS: Of 124,531 individuals who underwent carotid revascularization procedures, 91,687 (73.6%) underwent CEA, 17,247 (13.9%) underwent TFCAS, and 15,597 (12.5%) underwent TCAR. Among patients who met the CMS CAS criteria (ie, high-risk patients), the incidence of perioperative stroke was 2.7% for CEA, 3.4% for TFCAS, and 2.4% for TCAR (P < .001). Among standard-risk patients, the incidence of perioperative stroke was 1.7% for CEA, 2.7% for TFCAS, and 1.8% for TCAR (P < .001). After adjusting for baseline demographic and clinical characteristics, the odds of perioperative stroke were lower for TCAR versus CEA in high-risk patients (adjusted odds ratio [aOR], 0.82; 95% confidence interval [CI], 0.68-0.99) and similar in standard-risk patients (aOR, 1.05; 95% CI, 0.84, 1.31). In contrast, the adjusted odds of perioperative stroke were higher for TFCAS versus CEA in high-risk patients (aOR, 1.23; 95% CI, 1.03-1.46) and standard-risk patients (aOR, 1.60; 95% CI, 1.37-1.86). In both populations, TFCAS and TCAR patients had significantly lower odds of myocardial infarction than CEA patients (both P < .001). CONCLUSIONS: The perioperative risks associated with CEA, TFCAS, and TCAR in high-risk patients support the current CMS criteria, although the risks associated with each revascularization approach in standard-risk patients suggest that distinguishing TCAR from TFCAS may be warranted.

In-hospital and one-year outcomes are similar for women and men following transcarotid artery revascularization in symptomatic and asymptomatic patients.

OBJECTIVE: In randomized controlled trials and retrospective series, women have higher rates of periprocedural stroke and death following carotid endarterectomy and transfemoral carotid artery stenting compared with men. We sought to compare outcomes by sex following transcarotid artery revascularization (TCAR) among patients in the Vascular Quality Initiative (VQI). METHODS: We reviewed all patients in the VQI who underwent TCAR from 2017 to 2020. We stratified the analysis by symptom status. The primary outcome was in-hospital stroke/death, and secondary outcomes were in-hospital stroke and death and 1-year stroke/death, stroke, and death. We used multivariable logistic and Cox regression models to assess the association of sex with in-hospital and 1-year outcomes after adjusting for preoperative and intraoperative characteristics. RESULTS: We identified 15,851 patients who underwent TCAR, of whom 7391 (47%) were symptomatic (2708 or 37% female) and 8460 (53%) were asymptomatic (3097 or 37% female). Women were less frequently considered anatomic high risk than men in both groups (symptomatic: 43% vs 46%; P = .004; asymptomatic: 44% vs 48%; P = .004). Among symptomatic patients, women more often had severe ≥70% stenosis (89% vs 87%; P = .02). There were no differences in in-hospital death, stroke, or stroke/death for women vs men following TCAR among symptomatic or asymptomatic patients (all P > .05). After adjusting for baseline differences between groups, female sex was not associated with in-hospital stroke/death in either symptomatic (odds ratio, 1.05; 95% confidence interval, 0.72-1.56) or asymptomatic (odds ratio, 0.93; 95% confidence interval, 0.53-1.63) patients undergoing TCAR. There were also no differences in 1-year stroke, death, or stroke/death risk for women compared with men with and without symptoms on unadjusted or adjusted analyses (P > .05). CONCLUSIONS: We found no sex differences in in-hospital or 1-year stroke/death following TCAR, regardless of symptom status. TCAR appears to be as safe of a surgical procedure for women as for men in patients with both symptomatic and asymptomatic carotid artery disease.

Expedient Endovascular Hemorrhage Control During Anterior Lumbar Spinal Exposure Allows Procedural Completion in Rescued Patients.

OBJECTIVES: To propose a contemporary management strategy for venous injury during anterior lumbar spinal exposure that incorporates endovascular treatment. METHODS: Vein injuries suffered by patients treated in a single practice were reviewed. A treatment algorithm based on these experiences was formulated. RESULTS: Between 2015 and 2018, 914 patients received anterior access procedures for indicated lumbar interbody fusions. Of these patients, 15 (1.6%) suffered minor vascular injuries treated with manual pressure or suture repair. Four (0.4%) patients undergoing anterior lumbar spine surgery suffered major venous injuries, all of whom received the indicated spinal hardware following endovascular rescue. Primary repair was attempted in three patients before endovascular control and not at all in one. Vascular access was obtained via the bilateral femoral veins in 2 patients, unilateral femoral in one, and bilateral femoral plus right internal jugular vein in one. Stent choice included both uncovered (5, 63%) and covered stents (3, 38%). Deep venous thrombosis occurred in 2 patient's post-treatment. 1 DVT was encountered in the setting of a covered stent and 1 uncovered stent thrombosis was treated with catheter-directed lysis 4 weeks post-operatively. Ultimately, 3 patients were therapeutically anticoagulated. Mean follow-up is 13 months (range 1-36) with duplex ultrasounds available at 6 months or later in 3 of 4 patients. There is no evidence of post-thrombotic syndrome in the 2 patients that developed DVT's or in-stent stenosis in the 3 patients with available follow-up imaging. CONCLUSIONS: Endovascular techniques are important adjuncts when controlling large-volume hemorrhage associated with venous tears during anterior spinal exposure. Adequate direct compression allowing occlusion balloon inflation are key steps to reduce blood loss. Covered and uncovered stents are both appropriate choices to treat injuries. Patients must be anticoagulated post-operatively and surveilled for the sequelae of venous insufficiency. With expedient hemostasis, the indicated spinal surgery may be safely completed.

Increased Regional Market Competition is Associated with a Lower Threshold for Revascularization in Asymptomatic Carotid Artery Stenosis.

BACKGROUND: Revascularization practices with respect to asymptomatic carotid stenosis (ACAS) are known to vary widely among proceduralists. In addition, regional market competition has been previously shown to drive more aggressive practices in a number of surgical procedures. The aim of our study was to examine the association of regional market competition with revascularization thresholds for ACAS. METHODS: All patients undergoing carotid revascularization in the Vascular Quality Initiative carotid endarterectomy and stenting databases (2016-2020) were included. High-grade carotid stenosis was defined as ≥80%. We calculated the Herfindahl-Hirschman Index (HHI; a measure of physician market competition) for each U.S region as defined by the U.S Department of Health and Human Services. Logistic regression was used to examine the association of degree of carotid stenosis at revascularization with HHI stratified by symptomatology, adjusting for age, sex, race, insurance, and revascularization modality. RESULTS: Of 92,243 carotid interventions, 57,094 (61.9%) were performed for ACAS and 35,149 (38.1%) were performed for symptomatic carotid stenosis (SCAS). ACAS patients undergoing revascularization for moderate-grade stenosis were significantly less likely to be aspirin (85.6% vs. 86.3%), clopidogrel (41.3% vs. 45.1%), dual anti-platelet therapy (35.9% vs. 39.2%) and systemic anticoagulants (10.9 vs. 11.7%) compared to high-grade stenosis (all P < 0.05). Multivariable analysis demonstrated that decreased local market competition was independently associated with a lower odds of revascularization for moderate versus high-grade ACAS (odds ratio OR: 0.99 per 10 point increase in HHI, 95% confidence interval CI: 0.98-0.99). There was no association of local market competition with degree of carotid stenosis at time of revascularization among patients with SCAS (OR: 1.00 per 10 point increase in HHI, 95% CI: 0.99-1.00). Among ACAS patients, patients with moderate-grade stenosis had a higher odds ratio of in-hospital stroke or death compared to patients with high-grade stenosis (OR: 1.22, 95% CI 1.03-1.45). This association was not redemonstrated in the SCAS group (OR: 0.92, 95% CI: 0.80-1.06). CONCLUSIONS: Increased local market competition is associated with a lower threshold for revascularization of ACAS. There is no association between regional market competition and revascularization threshold for SCAS. These findings, combined with the significantly increased risk of perioperative stroke/death among moderate-grade ACAS patients, suggest that competition among proceduralists may result in a higher tolerance for increased operative risk in patients who might otherwise be reasonable candidates for surveillance.

Cadaver Simulation is Associated with Increased Comfort in Performing Open Vascular Surgery Among Integrated Vascular Surgery (0+5) Residents and Recent Graduates.

BACKGROUND: With the evolution in vascular surgery toward increased endovascular therapy and decreased open surgical training, comfort with open procedures by current trainees is declining. A proposed method to improve this discomfort is simulator training. We hypothesized that open, cadaver, and endovascular surgery simulation would be associated with increased self-perceived comfort in performing corresponding procedures. METHODS: Integrated (0 + 5) vascular surgery residents and recent graduates in the United States were asked to complete a survey quantifying comfort via a Likert scale with procedures and experience with simulation training. Simulation groups were then matched using coarsened exact matching. Ordinal logistic regression assessed the association between simulation experience and comfort in performing procedures. RESULTS: Surveys were completed by 68 trainees and 20 attending surgeons in their first 5 years of practice. On unmatched analyses, there were no significant differences in comfort in performing any open or endovascular aorto-mesenteric or peripheral vascular procedures between respondents who reported experience with open or endovascular simulation, respectively. However, respondents who reported cadaver simulation experience (58%, 51/88) had a significantly higher reported comfort score performing open juxtarenal aortic repair (2.4 vs. 1.7), superior mesenteric artery thrombectomy or bypass (2.5 vs. 1.9), inferior vena cava or iliac vein repair (2.2 vs. 1.7), axillary-femoral artery bypass (3.4 vs. 2.5), femoral-popliteal artery bypass (3.7 vs. 2.8), and inframalleolar artery bypass (2.8 vs. 2.1; all P < 0.05). After matching on training level, number of abdominal cases completed, and number of open vascular cases completed, ordinal logistic regression demonstrated that previous cadaver simulation was significantly associated with increased comfort in performing open aortic repairs, venous repair, visceral revascularization, and peripheral bypasses. CONCLUSIONS: In this nationally representative sample, cadaver, but not open or endovascular, simulation was associated with increased comfort in performing open vascular surgery. Providing cadaver simulation to trainees may help to improve comfort levels in performing open surgery. Integrated vascular surgery training programs should consider implementing these experiences into their curriculum.

Rescue of retinal ganglion cells in optic nerve injury using cell-selective AAV mediated delivery of SIRT1.

SIRT1 prevents retinal ganglion cell (RGC) loss in models of optic neuropathy following pharmacologic activation or genetic overexpression. The exact mechanism of loss is not known, prior evidence suggests this is through oxidative stress to either neighboring cells or RGC specifically. We investigated the neuroprotective potential of RGC-selective SIRT1 gene therapy in the optic nerve crush (ONC) model. We hypothesized that AAV-mediated overexpression of SIRT1 in RGCs reduces RGC loss, thereby preserving visual function. Cohorts of C57Bl/6J mice received intravitreal injection of experimental or control AAVs using either a ganglion cell promoter or a constitutive promoter and ONC was performed. Visual function was examined by optokinetic response (OKR) for 7 days following ONC. Retina and optic nerves were harvested to investigate RGC survival by immunolabeling. The AAV7m8-SNCG.SIRT1 vector showed 44% transduction efficiency for RGCs compared with 25% (P > 0.05) by AAV2-CAG.SIRT1, and AAV7m8-SNCG.SIRT1 drives expression selectively in RGCs in vivo. Animals modeling ONC demonstrated reduced visual acuity compared to controls. Intravitreal delivery of AAV7m8-SNCG.SIRT1 mediated significant preservation of the OKR and RGC survival compared to AAV7m8-SNCG.eGFP controls, an effect not seen with the AAV2 vector. RGC-selective expression of SIRT1 offers a targeted therapy for an animal model with significant ganglion cell loss. Over-expression of SIRT1 through AAV-mediated gene transduction suggests a RGC selective component of neuro-protection using the ONC model. This study expands our understanding of SIRT1 mediated neuroprotection in the context of compressive or traumatic optic neuropathy, making it a strong therapeutic candidate for testing in all optic neuropathies.

Antigen-Based Testing but Not Real-Time Polymerase Chain Reaction Correlates With Severe Acute Respiratory Syndrome Coronavirus 2 Viral Culture.

BACKGROUND: Individuals can test positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by molecular assays following the resolution of their clinical disease. Recent studies indicate that SARS-CoV-2 antigen-based tests are likely to be positive early in the disease course, when there is an increased likelihood of high levels of infectious virus. METHODS: Upper respiratory specimens from 251 participants with coronavirus disease 2019 symptoms (≤7 days from symptom onset) were prospectively collected and tested with a lateral flow antigen test and a real-time polymerase chain reaction (rt-PCR) assay for detection of SARS-CoV-2. Specimens from a subset of the study specimens were utilized to determine the presence of infectious virus in the VeroE6TMPRSS2 cell culture model. RESULTS: The antigen test demonstrated a higher positive predictive value (90%) than rt-PCR (70%) when compared to culture-positive results. The positive percentage agreement for detection of infectious virus for the antigen test was similar to rt-PCR when compared to culture results. CONCLUSIONS: The correlation between SARS-CoV-2 antigen and SARS-CoV-2 culture positivity represents a significant advancement in determining the risk for potential transmissibility beyond that which can be achieved by detection of SARS-CoV-2 genomic RNA. SARS-CoV-2 antigen testing can facilitate low-cost, scalable, and rapid time-to-result, while providing good risk determination of those who are likely harboring infectious virus, compared to rt-PCR.

A novel preoperative risk score for nonhome discharge after elective thoracic endovascular aortic repair.

BACKGROUND: Nonhome discharge (NHD) to a rehabilitation or skilled nursing facility after vascular surgery is poorly described despite its large impact on patients. Understanding postsurgical NHD risk is essential to providing adequate preoperative counseling and shared decision making, particularly for elective surgeries. We aimed to identify independent predictors of NHD after elective thoracic endovascular aortic repair (TEVAR) for thoracic aortic aneurysms (TAA) and to create a clinically useful preoperative risk score. METHODS: Elective TEVAR cases for descending TAA were queried from the Society for Vascular Surgery Vascular Quality Initiative from 2014 to 2018. A risk score was created by splitting the dataset into two-thirds for model development and one-third for validation. A parsimonious stepwise hierarchical multivariable logistic regression controlling for hospital level variation was performed in the development dataset, and the beta-coefficients were used to assign points for a risk score. This score was then cross-validated and model performance assessed. RESULTS: Overall, 1469 patients were included and 213 (14.5%) required NHD. At baseline, patients who required NHD were more likely to be ≥80 years old (35.2% vs 19.4%), female (58.7% vs 40.6%), functionally dependent (42.3% vs 24.0%), and anemic (46.5% vs 27.8%), and to have chronic obstructive pulmonary disease (41.3% vs 33.4%), congestive heart failure (18.8% vs 11.1%), and American Society of Anesthesiologists class ≥4 (51.6% vs 39.8%; all P < .05). Multivariable analysis in the development group identified independent predictors of NHD that were used to create an 18-point risk score. Patients were stratified into three groups based upon their risk score: low risk (0-7 points; n = 563) with an NHD rate of 4.3%, moderate risk (8-11 points; n = 701) with an NHD rate of 17.0%, and high risk (≥12 points; n = 205) with an NHD rate of 34.2%. The risk score had good predictive ability with a c-statistic of 0.75 for model development and a c-statistic of 0.72 in the validation dataset. CONCLUSIONS: This novel risk score can predict NHD after TEVAR for TAA using characteristics that can be identified preoperatively. The use of this score may allow for improved risk assessment, preoperative counseling, and shared decision making.

Racial Disparities Associated With Reinterventions After Elective Endovascular Aortic Aneurysm Repair.

BACKGROUND: There are substantial racial and socioeconomic disparities underlying endovascular abdominal aortic aneurysm repair (EVAR) in the United States. To date, race-based variations in reinterventions following elective EVAR have not been studied. Here, we aim to examine racial disparities associated with reinterventions following elective EVAR in a real-world cohort. MATERIALS AND METHODS: We used the Vascular Quality Initiative EVAR dataset to identify all patients undergoing elective EVAR between January 2009 and December 2018 in the United States. We compared the association of race with reinterventions after EVAR and all-cause mortality using Welch two-sample t-tests, multivariate logistic regression, and Cox proportional hazards analyses adjusting for baseline differences between groups. RESULTS: At median follow-up of 1.1 ± 1.1 y (1.3 ± 1.4 y Black, 1.1 ± 1.1 y White; P = 0.02), a total of 1,164 of 42,481 patients (2.7%) underwent reintervention after elective EVAR, including 2.7% (n = 1,096) White versus 3.2% (n = 68) Black (P = 0.21). Black patients requiring reintervention were more frequently female, more frequently current or former smokers, and less frequently insured by Medicare/Medicaid (P < 0.05). After adjusting for baseline differences, the risk of reintervention after elective EVAR was significantly lower for Black versus White patients (HR 0.74, 95% CI 0.55-0.99; P = 0.04). All-cause mortality was comparable between groups (HR 0.81, 95% CI 0.33-2.00, P = 0.65). CONCLUSIONS: There are significant differences between Black and White patients in the risk of reintervention after elective EVAR in the United States. The etiology of this difference deserves investigation.

A Bayesian Dirichlet process community occupancy model to estimate community structure and species similarity.

Community occupancy models estimate species-specific parameters while sharing information across species by treating parameters as sampled from a common distribution. When communities consist of discrete groups, shrinkage of estimates toward the community mean can mask differences among groups. Infinite-mixture models using a Dirichlet process (DP) distribution, in which the number of latent groups is estimated from the data, have been proposed as a solution. In addition to community structure, these models estimate species similarity, which allows testing hypotheses about whether traits drive species response to environmental conditions. We develop a community occupancy model (COM) using a DP distribution to model species-level parameters. Because clustering algorithms are sensitive to dimensionality and distinctiveness of clusters, we conducted a simulation study to explore performance of the DP-COM with different dimensions (i.e., different numbers of model parameters with species-level DP random effects) and under varying cluster differences. Because the DP-COM is computationally expensive, we compared its estimates to a COM with a normal random species effect. We further applied the DP-COM model to a bird data set from Uganda. Estimates of the number of clusters and species cluster identity improved with increasing difference among clusters and increasing dimensions of the DP; but the number of clusters was always overestimated. Estimates of number of sites occupied and species and community-level covariate coefficients on occupancy probability were generally unbiased with (near-) nominal 95% Bayesian Credible Interval coverage. Accuracy of estimates from the normal and the DP-COM was similar. The DP-COM clustered 166 bird species into 27 clusters regarding their affiliation with open or woodland habitat and distance to oil wells. Estimates of covariate coefficients were similar between a normal and the DP-COM. Except sunbirds, species within a family were not more similar in their response to these covariates than the overall community. Given that estimates were consistent between the normal and the DP-COM, and considering the computational burden for the DP models, we recommend using the DP-COM only when the analysis focuses on community structure and species similarity, as these quantities can only be obtained under the DP-COM.

Self-Perceived Comfort Performing Vascular Surgery Procedures among Senior Vascular Surgery Trainees and Recent Graduates.

OBJECTIVE: In the last two decades, vascular surgery training evolved from exclusively learning open skills to learning endovascular skills in addition to a functional reduction in training duration with 0+5 residency programs. The implications for this on trainee evolution to independence are unknown. We aimed to assess self-perceived comfort performing open and endovascular procedures and to identify predictors of high comfort among senior vascular surgery trainees and recent graduates. METHODS: Junior and senior 0+5 vascular surgery residents, traditional fellows, and attendings in their first 4 years of practice were asked to complete a survey assessing the number of vascular procedures performed to date, comfort performing these procedures on a Likert scale, and validated scales of self-efficacy and grit. Groups were then matched by training level and age. Logistic regression identified independent predictors of the top quartile of self-perceived comfort performing procedures. RESULTS: Surveys were completed by 92 trainees and 71 attending surgeons in their first 4 years of practice. After matching, completing ≥7 open juxtarenal aortic repairs (OR = 4.73, 95% CI = 1.59-14.07) and a higher self-efficacy score (OR = 3.24, 95% CI = 1.20-8.76), were independent predictors of top quartile comfort performing open vascular procedures. 0+5 residency training inversely correlated with top quartile comfort performing open vascular operations (OR = 0.12, 95% CI = 0.03-0.47). Completing ≥7 complex EVARs (OR = 3.94, 95% CI = 1.61-9.59) and a higher self-efficacy personality score (OR = 2.76, 95% CI = 1.09-7.02) were predictors of top quartile comfort performing endovascular procedures. CONCLUSION: In this nationally representative survey, both trainees and junior attendings completed a paucity of complex open vascular cases, which corresponded to reduced comfort performing these procedures. Furthermore, 0+5 residency training was associated with lower self-perceived comfort performing open vascular surgery, a trend that persisted through the first years of practice. Endovascular comfort did not show a similar correlation.

Aortic Neck IFU Violations During EVAR for Ruptured Infrarenal Aortic Aneurysms are Associated with Increased In-Hospital Mortality.

OBJECTIVE: Vascular surgeons treating patients with ruptured abdominal aortic aneurysm must make rapid treatment decisions and sometimes lack immediate access to endovascular devices meeting the anatomic specifications of the patient at hand. We hypothesized that endovascular treatment of ruptured abdominal aortic aneurysm (rEVAR) outside manufacturer instructions-for-use (IFU) guidelines would have similar in-hospital mortality compared to patients treated on-IFU or with an infrarenal clamp during open repair (ruptured open aortic aneurysm repair [rOAR]). METHODS: Vascular Quality Initiative datasets for endovascular and open aortic repair were queried for patients presenting with ruptured infrarenal AAA between 2013-2018. Graft-specific IFU criteria were correlated with case-specific proximal neck dimension data to classify rEVAR cases as on- or off-IFU. Univariate comparisons between the on- and off-IFU groups were performed for demographic, operative and in-hospital outcome variables. To investigate mortality differences between rEVAR and rOAR approaches, coarsened exact matching was used to match patients receiving off-IFU rEVAR with those receiving complex rEVAR (requiring at least one visceral stent or scallop) or rOAR with infrarenal, suprarenal or supraceliac clamps. A multivariable logistic regression was used to identify factors independently associated with in-hospital mortality. RESULTS: 621 patients were treated with rEVAR, with 65% classified as on-IFU and 35% off-IFU. The off-IFU group was more frequently female (25% vs. 18%, P = 0.05) and had larger aneurysms (76 vs. 72 mm, P= 0.01) but otherwise was not statistically different from the on-IFU cohort. In-hospital mortality was significantly higher in patients treated off-IFU vs. on-IFU (22% vs. 14%, P= 0.02). Off-IFU rEVAR was associated with longer operative times (135 min vs. 120 min, P= 0.004) and increased intraoperative blood product utilization (2 units vs. 1 unit, P= 0.002). When off-IFU patients were matched to complex rEVAR and rOAR patients, no baseline differences were found between the groups. Overall in-hospital complications associated with off-IFU were reduced compared to more complex strategies (43% vs. 60-81%, P< 0.001) and in-hospital mortality was significantly lower for off-IFU rEVAR patients compared to the supraceliac clamp group (18% vs. 38%, P= 0.006). However, there was no significantly increased mortality associated with complex rEVAR, infrarenal rOAR or suprarenal rOAR compared to off-IFU rEVAR (all P> 0.05). This finding persisted in a multivariate logistic regression. CONCLUSIONS: Off-IFU rEVAR yields inferior in-hospital survival compared to on-IFU rEVAR but remains associated with reduced in-hospital complications when compared with more complex repair strategies. When compared with matched patients undergoing rOAR with an infrarenal or suprarenal clamp, survival was no different from off-IFU rEVAR. Taken together with the growing available evidence suggesting reduced long-term durability of off-IFU EVAR, these data suggest that a patient's comorbidity burden should be key in making the decision to pursue off-IFU rEVAR over a more complex repair when proximal neck violations are anticipated preoperatively.

Closure device use for common femoral artery antegrade access is higher risk than retrograde access.

OBJECTIVE: Although the use of closure devices (CD) for femoral artery antegrade access (AA) is not in the instructions for use (IFU) for many devices, AA has been reported to be associated with a lower incidence of access site complications compared to manual compression alone. We hypothesized that CD use for AA would not be associated with a clinically significant increased odds of access site complications compared to CD use for retrograde access (RA). METHODS: This was a retrospective review of the Vascular Quality Initiative from 2010 to 2019 for infrainguinal peripheral vascular interventions with common femoral artery access closed with a CD. Patients who had a cutdown or multiple access sites were excluded. Cases were then stratified into whether access was antegrade or retrograde. Hierarchical multivariable logistic regressions controlling for hospital level variation were used to examine the independent association between AA and access site complications. The primary outcomes were access site hematoma, stenosis, or occlusion as defined in the VQI. The secondary outcome was the development of an access site hematoma requiring an intervention, which was defined as transfusion, thrombin injection, or surgery. Sensitivity analyses after coarsened exact matching were performed to reduce residual bias. RESULTS: Overall, 72,463 cases were identified and 6,070 (8.4%) had AA. Patients with AA were less likely to be smokers (27.2% vs 33.0%) or obese (31.5% vs 35.6%; all P<0.05). Patients with AA were more likely to be on dialysis (12.8% vs 10.1%) and have ultrasound-guided access (76.4% vs 66.2%; P<0.05 for all). Compared to RA, patients with AA were more likely to develop any access site hematoma (2.5% vs 1.8%; P<0.01) and a hematoma requiring intervention (0.7% vs 0.5%; P=0.03), but had no difference in access site stenosis or occlusion (0.3% vs 0.2%; P=0.21). On multivariable analyses, AA had increased odds of developing any access site hematoma (OR=1.46; 95% CI=1.22-1.76) and a hematoma requiring intervention (OR=1.48; 95% CI=1.10-1.98). Sensitivity analyses after coarsened exact matching confirmed these findings. CONCLUSION: In this nationally representative sample, the use of CDs for femoral access was associated with an overall low rate of access site complications. However, there was an increased odds of access site hematomas with AA. Patient selection for AA remains important and ultrasound guided access should be the standard of care for this approach.

Contemporary Experience with Paravisceral Aortic Aneurysm (PVAAA) Repair in a Tertiary Center.

OBJECTIVES: To describe contemporary outcomes from a single center capable of both complex open and endovascular aortic repair for paravisceral aortic aneurysms (PVAAA). METHODS: Data on all patients receiving open or endovascular (endo) treatment for aortic aneurysms with proximal extent at or above the renal arteries and distal to the inferior pulmonary ligament (IPL) were reviewed. Coarsened exact matching (CEM) on age, aneurysm type, gender, coronary artery disease (CAD), previous aortic surgery and symptomatic status created balanced cohorts for outcomes comparisons. RESULTS: Between October, 2006 and February, 2018, 194 patients were treated for juxtarenal (40%), pararenal (21%), paravisceral (6%) and Type 4 thoracoabdominal (34%) aortic aneurysms with open (81, 42%) or endo (113, 58%) at a single tertiary center. Endo repairs included renal coverage with a bifurcated graft (2%), unilateral (13%) or bilateral (4%) renal snorkels, Z-fen (15%), multi-branched graft (IDE protocol; 62%) and unique complex configurations (4%). On multivariable analysis, patients selected for open surgery were more likely to be symptomatic, whereas older patients, female patients and those with Type 4 TAAA extent were more often selected for endovascular treatment. Matching based on the significant independent covariates reduced the open and endovascular groups by one-third. Survival at 30 days was 97% for endo and 94% for open repair, 98% for both subgroups when excluding symptomatic cases, and was not different between the matched groups (98% vs 89%; P=0.23). Hospital and ICU stays were longer in open patients (8 vs. 10 days, 2 vs. 4, both P≤0.001). Post-op CVA, MI, lower extremity ischemia, surgical site infections and reoperation were not different between matched groups (all p>0.05), while pulmonary and intestinal complications, as well as grade 1/2 renal dysfunction by RIFLE criteria, were more common after open repair (all P<0.05). Spinal cord ischemia was significantly more frequent in the unmatched Endo group (11% vs. 1%, P=0.02), but this difference was not significant after matching. Composite major aortic complications was no different between treatment groups (unmatched P=0.91, matched P=0.87). Endo treatment resulted in patients more frequently discharged to home (84% vs. 66%, P=0.02). Reintervention after 30 days occurred more frequently in the endo group (P=0.002). Estimated survivals at 1 and 5 years for endo and open are 96% vs. 81% and 69% vs. 81% respectively (Log-rank P=0.57). CONCLUSIONS: Contemporary repair of PVAAA demonstrates safe outcomes with durable survival benefit when patients are well-selected for open or complex endovascular repair. We believe these data have implications for off-label device use in the treatment of PVAAA, and that open repair remains an essential option for younger, good risk patients in experienced centers.

Depression Predicts Non-Home Discharge After Abdominal Aortic Aneurysm Repair.

BACKGROUND: Mental health's impact on vascular surgical patients has long been overlooked. While outside the expertise of most surgeons, understanding the role that depression plays in the postoperative course could provide additional insight into opportunities to improve surgical outcomes and healthcare value. Additionally, non-home discharge (NHD) to a rehabilitation or skilled nursing facility after surgery is associated with impaired quality of life and higher postdischarge complications, readmissions, and mortality. We hypothesized that depression would be associated with an increased risk for NHD following abdominal aortic aneurysm (AAA) repair. METHODS: Nonruptured AAA repair cases were identified from the National Inpatient Sample (NIS) using ICD-9 codes between 2005 and 2014. Depression, comorbidities, postoperative complications, and discharge destination were evaluated using statistical tests as appropriate to the data. A hierarchical multivariable logistic regression controlling for hospital level variation was used to examine the independent association between depression, and the primary outcome of NHD controlling for median income and confounders meeting P < 0.05 on univariate analysis. RESULTS: There were 99,934 total cases analyzed, of which 4,755 (4.8%) were diagnosed with depression and 10,618 (11.9%) required NHD. Patients with depression were younger, more likely to be women, white, have diabetes, chronic obstructive pulmonary disease, hypertension, tobacco use, and more likely to experience a postoperative complication. On adjusted multivariable analysis, patients with depression were more likely to require NHD (odds ratio [OR] 1.87, 95% confidence interval [CI]: 1.68-2.08, c-statistic = 0.82). On stratified analysis by operative approach, depression had a larger effect estimate in endovascular repair (OR 2.19; 95% CI: 1.90-2.52) versus open repair (OR 1.60; 95% CI: 1.38-1.87). CONCLUSIONS: In a nationally representative sample, patients with depression were more likely to require NHD after AAA repair. This study highlights the importance that depression plays in postoperative outcomes after AAA repair. Furthermore, addressing mental health preoperatively has the potential to improve outcomes in patients undergoing AAA repair.