Radial arterial access is a safe alternative to brachial artery and femoral artery access for endovascular lower extremity peripheral arterial disease.

OBJECTIVE: Radial artery access is a well-described technique that has proven to be safe and efficacious in percutaneous cardiac intervention. This technique has been used with increased frequency in the treatment of lower extremity peripheral arterial disease (LE-PAD); however, the overall safety has not yet been well described in the vascular surgery literature. We sought to evaluate the safety of this technique compared with retrograde femoral artery access and brachial artery access (BA) in the treatment of PAD. METHODS: The Vascular Quality Initiative database was used to identify all patients who underwent single site percutaneous access (retrograde femoral access [FA], BA, radial access [RA]) for treatment of LE-PAD from September 2016 through September 2019. Patients who underwent multiple access sites for intervention were excluded. Primary outcome was significant access site complications (ASCs), defined as those requiring treatment (blood transfusion, interventional treatment, or surgical treatment). Minor ASCs were also reported. RESULTS: The cohort comprised 61,203 patients (270 RA, 1210 BA, and 59,723 FA) with an average age of 68 years and who were 59.6% male. The RA and BA groups had higher rates of prior endarterectomy or bypass compared with the FA group (66.7% RA; 86.0% BA; 50.2% FA; P < .001). RA was more often used for single-segment treatments (82% vs 74% [P < .020] and more aortoiliac arterial segments (59.6% vs 21.0% [P < .001]). ASC occurred in 1329 patients (2.7%), including minor ASC (996 [1.6%]) and significant ASC (333 [0.54%]). Significant ASC were less common after FA and RA compared with BA (RA, 1 [0.37%]; FA, 307 [0.51%]; BA, 25 [2.1%]; P < .001). On multivariate analysis, BA was the strongest predictor of significant ASC (odds ratio, 2.75; 95% confidence interval, 1.73-4.36; P < .001). Significant ASC was no different after RA compared with FA (odds ratio, 0.60; 95% confidence interval, 0.08-4.33; P = .616). Other factors independently associated with significant ASC were sex, age, diabetes, chronic obstructive pulmonary disease, dialysis, and closure device use. CONCLUSIONS: RA as the primary access vessel for endovascular treatment of LE-PAD is safe when compared with other traditional access sites. When FA is not possible or desirable, the radial approach may provide suitable access to treatment with a better safety profile than BA.

Chinook salmon diversity contributes to fishery stability and trade-offs with mixed-stock harvest.

Variation among populations in life history and intrinsic population characteristics (i.e., population diversity) helps maintain resilience to environmental change and dampen interannual variability in ecosystem services. As a result, ecological variation, and the processes that generate it, is considered central to strategies for managing risks to ecosystems in an increasingly variable and uncertain world. However, characterizing population diversity is difficult, particularly in large and remote regions, which often prevents its formal consideration in management advice. We combined genetic stock identification of archived scale and tissue samples with state-space run-reconstruction models to estimate migration timing and annual return abundance for eight geographically and genetically distinct Chinook salmon populations within the Canadian portion of the Yukon River. We found that among-population variation in migration timing and return abundances resulted in aggregate return migrations that were 2.1 times longer and 1.4 times more stable than if they had composed a single homogeneous population. We then fit state-space spawner-recruitment models to the annual return abundances to characterize among-population diversity in intrinsic productivity and population size and their consequences for the fisheries they support. Productivity and carrying capacity varied among populations by approximately 2.4-fold (2.9 to 6.9 recruits per spawner) and three-fold (8800 to 27,000 spawners), respectively. This diversity implies an equilibrium trade-off between harvesting of the population aggregate and the conservation of individual populations whereby the harvest rate predicted to maximize aggregate harvests comes at the cost of overfishing ~40% of the populations but with a relatively low risk of extirpating the weakest ones. Our findings illustrate how population diversity in one of the largest salmon-producing river basins in the world contributes to fishery stability and food security in a region where salmon have high cultural and subsistence value. More generally, our work demonstrates the utility of molecular analyses of archived biological material for characterizing diversity in biological systems and its benefits and consequences for trade-offs in decision-making.

Medical Student Perspectives on Choosing a Career in Vascular Surgery.

BACKGROUND: Vascular surgery is facing an impending workforce shortage as the population ages and the demand for vascular surgical services increases. The integrated vascular surgery residency (0+5) paradigm is well-established and provides a mechanism to increase the number of board-certified vascular surgeons. Recruitment of medical students to these programs has proven challenging with unfilled positions in each of the past 2 years. The aim of this study is to explore factors that influence medical students' interest in vascular surgery and their decision to ultimately pursue a career in the field. METHODS: Medical students listed on the Society for Vascular Surgery "Find a VSIG (Vascular Surgery Interest Group)" webpage were contacted via email to participate in the study. A snowball sampling technique was employed to recruit additional participants, including recent medical school graduates who had matched into a 0+5 program. Fifteen students participated in 5 focus groups. Directed content analysis was employed to qualitatively analyze focus group transcripts. RESULTS: Five domains were identified as influencing students' decision to pursue vascular surgery. Experiential learning facilitated early exploration of the field. The intellectuality of the specialty was a feature that attracted students to vascular surgery. In addition, the professional identify of vascular surgeons as comprehensive care providers was appealing. Students identified with their mentors' relationships as observed during clinical encounters. Long-term mentorship was important in sustaining students' interest. CONCLUSION: Medical students pursue a career in vascular surgery based on early exposure to the specialty, experiential learning through hands-on VSIG events, clinical experiences, and longitudinal faculty mentorship. The unique aspects of the specialty, including professional identity and intellectuality, should be highlighted to both attract and maintain students' interest in the field. These findings can be used by national vascular surgery leaders, practicing vascular surgeons, and faculty and student leadership of VSIGs to optimize recruitment programs and increase the vascular surgery workforce.

Risk factors for recanalization of truncal veins following endoluminal ablation.

BACKGROUND: Recanalization of target veins after treatment of superficial venous incompetence has clinical implications and may depend on the type of intervention. The aim of this study was to evaluate patient and procedural factors associated with truncal vein recanalization in a large study cohort using the Vascular Quality Initiative (VQI) Varicose Vein Registry. METHODS: We performed a retrospective review using the VQI Varicose Vein Registry from 2014 to 2018. We evaluated all procedures performed for truncal venous insufficiency. Demographic data and information about treatment modality were collected. Patients were separated into recanalization and nonrecanalization groups based on the status of the treated vein at follow-up ultrasound examination. The vein was only considered recanalized if the VQI noted complete recanalization of the target vein. Univariate and multivariate comparisons were performed as appropriate. RESULTS: A total of 10,604 procedures were performed in 7403 patients. The average age was 55.9 years and 70.3% of the patients were female. Patients with recanalization were more likely to have a history of phlebitis (P < .001) and had a higher mean body mass index (30.5 vs 32., kg/m2 ; P = .006) compared with those without recanalization. There was no difference in the use of compression therapy, anticoagulation, deep venous reflux, number of pregnancies, prior deep vein thrombosis, Venous Clinical Severity Score, and clinical-etiology-anatomy-pathophysiology between patients with and without recanalization. The number of truncal veins treated per procedure was higher in the recanalization group compared with the nonrecanalization group (2.36 vs 1.88; P = .001). After multivariate logistic regression, laser ablation was associated with higher rate of recanalization compared with radiofrequency ablation (P = .017). CONCLUSIONS: This study is the first to use VQI based data to describe risk factors for recanalization following treatment of truncal venous reflux. The use of laser ablation for truncal veins is associated with a higher risk for recanalization compared with radiofrequency ablation. Obesity, prior phlebitis, and number of veins treated were independently associated with increased rate of recanalization.

Symptomatic carotid stenosis in Eagle syndrome managed with traditional endarterectomy and styloidectomy.

Eagle syndrome represents an anatomic variant present in 4% of the population. It is characterized by an elongated styloid process or ossified stylohyoid ligament with resultant irritation of cervical neurovascular structures. Common manifestations include craniofacial or cervical pain related to compression of the glossopharyngeal nerve. In rare cases, patients can present with a stroke or transient ischemic attack due to associated carotid artery injury. Fewer than 25 prior case reports describe vascular symptoms in the setting of associated carotid artery dissection and, in one case, a pseudoaneurysm. Our case report details the diagnosis and management of symptomatic carotid artery stenosis secondary to vascular Eagle syndrome.

Use of a prosthetic conduit for stent delivery in transcarotid artery revascularization for patients with unfavorable anatomy.

Transcarotid artery revascularization (TCAR) provides a safe alternative to carotid endarterectomy. The anatomic requirements include a 5-cm minimum clavicle to carotid bifurcation distance for sheath access proximal to the lesion. In the present report, we describe our experience with conduit use for patients not meeting that requirement. Patients undergoing elective TCAR with a conduit from 2021 to 2022 were retrospectively identified. After carotid artery exposure, a 6-mm prosthetic graft was anastomosed to the common carotid artery in an end-to-side fashion. After stent delivery, the conduit was ligated and oversewn. The patient demographics, procedural details, and outcomes were recorded and compared with our nonconduit TCAR experience. A total of 11 patients (64% male; age, 75 ± 5 years) underwent TCAR with a conduit, 5 (46%) for symptomatic disease, and 77 patients underwent TCAR with no conduit, 52 (60%) with symptomatic disease (P = .50). Other than a higher rate of prior coronary interventions in the conduit group (55% vs 47%; P = .007), no significant differences were found in age, gender, race, comorbidities, or high risk for carotid endarterectomy criteria. In the conduit group, the average skin to carotid artery depth was 4.2 cm (range, 1.9-6.1 cm). The average clavicle to bifurcation distance was 4.4 cm (range, 3.3-4.9 cm) vs 6.5 cm (range, 3.3-9.7 cm; P = .002) in the nonconduit group. Dacron was the most common conduit material used (73%). No differences were found in the mean procedure times (121 ± 32 vs 129 ± 53 minutes; P = .785) or flow reversal times (14 ± 5 vs 19 ± 13 minutes; P =.989) for the conduit and nonconduit cohorts, respectively. Technical success was achieved in 100% of the conduit and nonconduit cases. Excluding one outlier of a prolonged stay (7 days) for management of unrelated medical issues (gastrostomy tube placement for chronic dysphagia after mass resection and neck radiation), the mean hospital stay was 2 days (1.2 ± 0.4 intensive care unit days) compared with 3.8 ± 5.7 days for our nonconduit cohort (P = .2). Hypotension was the most common reason for delayed discharge for the conduit group (n = 3; 27%). The average follow-up was 2.7 months (range, 1-10 months). For all 11 conduit patients, the stent remained patent without stenosis, thrombus, or pseudoaneurysm at the conduit stump site on surveillance duplex ultrasound. No strokes or complications had occurred at 30 days in the conduit group compared with four strokes or transient ischemic attacks (P = .469) and 18 minor complications in the nonconduit group (P = .091). For patients lacking a sufficient distance between the clavicle and carotid artery bifurcation, a prosthetic conduit facilitates safe use of flow reversal for stent delivery and can be ligated at procedural completion without consequences.

How We Do It: A Multicenter National Experience of Virtual Vascular Surgery Rotations.

OBJECTIVE: To describe the development and implementation of virtual vascular surgery rotations among 6 integrated vascular surgery programs. DESIGN: A collaborative teleconference retrospectively discussing 6 independently developed virtual vascular surgery rotations to make a framework for future use. SETTING: University of California Davis initiated a joint teleconference among the various integrated vascular surgery programs. PARTICIPANTS: Vascular surgery faculty and residents from 6 programs participated in the teleconferences and drafting of a framework for building a virtual vascular surgery rotation. RESULTS: Four specific domains were identified in discussing the framework to build a virtual vascular surgery rotation: planning, development, curriculum, and feedback. Each domain has specific aspects in making a virtual rotation that has applicability to other surgical rotations that seek to do the same. CONCLUSION: Virtual vascular surgery rotations are feasible and important; these electives can be established and implemented successfully with appropriate planning and consideration. This work hopes to help programs navigate this new space in education by making it more transparent and highlighting potential pitfalls.

Challenges of treating mixed arterial-venous disease of lower extremities.

INTRODUCTION: Mixed arterial-venous lower extremity disease (AVLED) poses a unique challenge for clinicians. This review will outline the impact mixed AVLED has on patients and the healthcare system, by reviewing its epidemiology, diagnosis, current treatment, and the challenges encountered implementing therapies. EVIDENCE ACQUISITION: An extensive search of current literature from online sources, journals and book chapters identified the current challenges facing the treatment of mixed arterial venous ulcers of the lower extremities and potential solutions to these challenges. EVIDENCE SYNTHESIS: The challenges that are identified in the search are the time to heal AVLED, patient education and motivation, early detection of AVLED, wound care center development, treatment consensus from multidisciplinary team members, and cost of treatment. CONCLUSIONS: AVLED ulcers are a challenging problem, but over time we have continued and will continue to improve patient care and tackle these difficult challenges as we have throughout the last century. A diagnostic algorithm to address how we approach these patients in terms of conservative care with wound care and compression and treat arterial and venous insufficiency is crucial. In looking to the future, continued standardization of wound care centers will overcome the social and financial challenges faced by patients and continued clinical research will improve targeted therapies and treatment challenges faced by physicians.

Virtual medical student education and recruitment during the COVID-19 pandemic.

Due to the immediate need for social distancing, as well as widespread disruption in clinical practices, brought on by the novel severe acute respiratory syndrome coronavirus 2 (COVID-19) pandemic, medical student education rapidly shifted to a virtual format, which resulted in a variety of innovative and remotely accessible practices to address new restrictions on face-to-face education. Educators approached curriculum design seeking to replicate as much of the in-person experience as possible, and were faced with overcoming the challenges of replacing the innately hands-on nature of surgery with virtual operative and skills experiences. Restrictions on in-person visiting electives expedited the role of virtual education as a notable opportunity for medical student education and recruitment, with a variety of approaches to engaging undergraduate medical learners, including the use of live-streaming operative cases, virtual didactic curricula, and a rise in podcasts; web-based conferences; and virtual journal clubs. In addition to education, virtual outreach to medical students has become an essential tool in trainee recruitment and selection, and ongoing application of novel educational platforms will allow for new opportunities in multi-institutional collaboration and exchange with a multitude of benefits to future vascular surgery trainees. Our aim was to outline the resources and practices used to virtually teach and recruit medical students and the benefits of virtual rotations to the program and students.

Endovascular repair of an innominate artery pseudoaneurysm using the Valiant Mona LSA branched graft device.

A 60-year-old woman involved in a motor vehicle collision presented with a traumatic pseudoaneurysm of the innominate artery origin in addition to multiple concomitant injuries. She was classified as a high-risk candidate for open repair. An experimental thoracic branched graft device was used for coverage of the injury with the addition of a right carotid-to-left carotid-to-left subclavian artery bypass. Follow-up imaging showed resolution of the pseudoaneurysm and patency of her bypass grafts. This is the first described use of the Mona LSA Branch Thoracic Stent Graft System (Medtronic, Minneapolis, Minn) in the innominate artery.

Location is everything: evaluating the effects of terrestrial and marine resource subsidies on an estuarine bivalve.

Estuaries are amongst the world's most productive ecosystems, lying at the intersection between terrestrial and marine environments. They receive substantial inputs from adjacent landscapes but the importance of resource subsidies is not well understood. Here, we test hypotheses for the effects of both terrestrial- and salmon-derived resource subsidies on the diet (inferred from stable isotopes of muscle tissue), size and percent nitrogen of the soft-shell clam (Mya arenaria), a sedentary estuarine consumer. We examine how these relationships shift across natural gradients among 14 estuaries that vary in upstream watershed size and salmon density on the central coast of British Columbia, Canada. We also test how assimilation and response to subsidies vary at smaller spatial scales within estuaries. The depletion and enrichment of stable isotope ratios in soft-shell clam muscle tissue correlated with increasing upstream watershed size and salmon density, respectively. The effects of terrestrial- and salmon-derived subsidies were also strongest at locations near stream outlets. When we controlled for age of individual clams, there were larger individuals with higher percent nitrogen content in estuaries below larger watersheds, though this effect was limited to the depositional zones below river mouths. Pink salmon exhibited a stronger effect on isotope ratios of clams than chum salmon, which could reflect increased habitat overlap as spawning pink salmon concentrate in lower stream reaches, closer to intertidal clam beds. However, there were smaller clams in estuaries that had higher upstream pink salmon densities, possibly due to differences in habitat requirements. Our study highlights the importance of upstream resource subsidies to this bivalve species, but that individual responses to subsidies can vary at smaller scales within estuaries.

Ecosystemic effects of salmon farming increase mercury contamination in wild fish.

Net-pen salmon aquaculture has well-known effects on coastal ecosystems: farm waste increases sediment organic content and the incidence of sediment anoxia, supports increased production of deposit-feeding invertebrates, and attracts higher densities of demersal fish and other mobile carnivores. These impacts are widely considered to be localized and transitory, and are commonly managed by imposing a period of fallowing between cycles of production. The implications of these ecosystemic effects for contaminant cycling, however, have not previously been considered. We found elevated levels of mercury in demersal rockfishes near salmon farms in coastal British Columbia, Canada, attributable to a combination of higher rockfish trophic position and higher mercury levels in prey near farms. Mercury concentrations in long-lived species such as rockfishes change over a longer time scale than cycles of production and fallowing, and thus at least some important effects of fish farms may not be considered transitory.