Faculty Bibliography

OBJECTIVES/OBJECTIVE:Generative artificial intelligence (AI) has emerged as a promising tool to engage with patients. The objective of this study was to assess the quality of AI responses to common patient questions regarding vascular surgery disease processes. METHODS:OpenAI's ChatGPT-3.5 and Google Bard were queried with 24 mock patient questions spanning seven vascular surgery disease domains. Six experienced vascular surgery faculty at a tertiary academic center independently graded AI responses on their accuracy (rated 1-4 from completely inaccurate to completely accurate), completeness (rated 1-4 from totally incomplete to totally complete), and appropriateness (binary). Responses were also evaluated with three readability scales. RESULTS:> .05 for all analyses). CONCLUSIONS:AI offers a novel means of educating patients that avoids the inundation of information from "Dr Google" and the time barriers of physician-patient encounters. ChatGPT provides largely valid, though imperfect, responses to myriad patient questions at the expense of readability. While Bard responses are more readable and concise, their quality is poorer. Further research is warranted to better understand failure points for large language models in vascular surgery patient education.

OBJECTIVE:Acute limb ischemia (ALI) is associated with high rates of amputation and consequent morbidity and mortality. The objective of this study is to report on the safety and efficacy of aspiration thrombectomy using the Indigo Aspiration System in patients with lower extremity (LE) ALI. METHODS:The STRIDE study was an international, multicenter, prospective, study that enrolled 119 participants presenting with LE-ALI. Patients were treated firstline with mechanical thrombectomy using the Indigo Aspiration System, before stenting or angioplasty, or other therapies as determined by treating physician. The primary end point was target limb salvage at 30 days after the procedure. Secondary end points within 30 days included technical success, defined as core laboratory-adjudicated Thrombolysis in Myocardial Infarction (TIMI) 2/3 flow rate immediately after the procedure, changes in modified Society for Vascular Surgery runoff score, improvement of Rutherford classification compared with before the procedure, patency, rate of device-related serious adverse events, and major periprocedural bleeding. Secondary end points that will be evaluated at 12 months include target limb salvage and mortality. RESULTS:Of the 119 participants enrolled at 16 sites, the mean age was 66.3 years (46.2% female). At baseline (n = 119), ischemic severity was classified as Rutherford I in 10.9%, Rutherford IIa in 54.6%, and Rutherford IIb in 34.5%. The mean target thrombus length was 125.7 ± 124.7 mm. Before the procedure, 93.0% (of patients 107/115) had no flow (TIMI 0) through the target lesion. The target limb salvage rate at 30 days was 98.2% (109/111). The rate of periprocedural major bleed was 4.2% (5/119) and device-related serious adverse events was 0.8% (1/119). Restoration of flow (TIMI 2/3) was achieved in 96.3% of patients (105/109) immediately after the procedure. The median improvement in the modified Society for Vascular Surgery runoff score (before vs after the procedure) was 6.0 (interquartile range, 0.0-11.0). Rutherford classifications also improved after discharge in 86.5% of patients (83/96), as compared with preprocedural scores. Patency at 30 days was achieved in 89.4% of patients (101/113). CONCLUSIONS:In the STRIDE (A Study of Patients with Lower Extremity Acute Limb Ischemia to Remove Thrombus with the Indigo Aspiration System) study, aspiration thrombectomy with the Indigo System provided a safe and effective endovascular treatment for patients with LE-ALI, resulting in a high rate (98.2%) of successful limb salvage at 30 days, with few periprocedural complications.

OBJECTIVE:Investigations into imaging modalities in the diagnosis of extracranial carotid artery occlusion (CAO) have raised questions about the inter-modality comparability of duplex ultrasound (DUS) and cross-sectional imaging (CSI). This study examines the relationship between DUS and CSI diagnoses of extracranial CAO. METHODS:This single-institution retrospective analysis studied patients with CAO diagnosed by DUS from 2010 to 2021. Patients were identified in our office-based accredited vascular laboratory database. Imaging and clinical data was obtained via our institutional electronic medical record. Primary outcome was discrepancy between DUS and CSI modalities. Secondary outcomes included incidence of stroke and intervention subsequent to CAO diagnosis. RESULTS:Of our 140-patient cohort, 95 patients (67.9%) had DUS follow-up (mean, 42.7 ± 31.3 months). At index duplex, 68.0% of individuals (n = 51) were asymptomatic. Seventy-five patients (53.6%) had CSI of the carotids after DUS CAO diagnosis; 18 (24%) underwent magnetic resonance imaging and 57 (76%) underwent computed tomography. Indications for CSI included follow-up of DUS findings of carotid stenosis/occlusion (44%), stroke/transient ischemic attack (16%), other symptoms (12%), preoperative evaluation (2.7%), unrelated pathology follow-up (9.3%), and outside institution imaging with unavailable indications (16%). When comparing patients with CSI and those without, there were no differences with regard to symptoms at diagnosis, prior neck interventions, or hypertension. There was a significant difference between cross-sectionally imaged and non-imaged patients in anti-hypertensive medications (72% vs 53.8%; P = .04). Despite initial DUS diagnoses of carotid occlusion, 10 patients (13.3%) ultimately had CSI indicating patent carotids. Four of these 10 patients had stenoses of ∼99% (with 1 string sign), four of 70% to 99%, one of 50% to 69%, and one of less than 50% on CSI. The majority of patients (70%) had CSI within 1 month of the index ultrasound. There were no significant relationships between imaging discrepancies and body mass index, heart failure, upper body edema, carotid artery calcification, and neck hardware. Eight individuals (10.7%) underwent ipsilateral revascularization; 62.5% (n = 5) were carotid endarterectomy procedures, and the remaining three procedures were a transcervical carotid revascularization, subclavian to internal carotid artery bypass, and transfemoral carotid artery stenting. Eight patients (10.7%) underwent contralateral revascularization, with the same distribution of procedures as those ipsilateral to occlusions. Two of the 10 patients with discrepancies underwent carotid endarterectomy, and one underwent carotid stenting. CONCLUSIONS:In our experience, duplex diagnosis of CAO is associated with a greater than 10% discordance when compared with CSI. These patients may benefit from closer surveillance as well as confirmatory computed tomography or magnetic resonance angiography. Further work is needed to determine the optimal diagnostic modality for CAO.

BACKGROUND:Duplex-derived velocity measurements are often used to determine the need for carotid revascularization. There is evidence that severe ipsilateral carotid stenosis can cause artificially elevated velocities in the contralateral carotid artery, which may decrease following ipsilateral revascularization. The objective of this study was to determine if contralateral carotid artery duplex velocities decrease following ipsilateral carotid endarterectomy or stenting procedures. METHODS:This is a single institutional retrospective study of prospectively collected data on all patients who underwent carotid revascularization from 2013 to 2021. Patients with immediate preoperative and first postoperative Duplex scan within 4 months of carotid revascularization at our vascular laboratory were included for analysis. Patients with contralateral occlusion were excluded. Duplex criteria used to define moderate (50-69%) and severe (>70%) stenosis were systolic velocity ≥125 cm/sec and ≥230 cm/sec, respectively. RESULTS:Between 2013 and 2021, 129 patients with bilateral carotid stenosis underwent either carotid endarterectomy (98) or a stenting procedure (31). The majority of patients (90%) underwent intervention for severe stenosis. Preoperatively, the contralateral artery was categorized as severe in 30.4% patients. After ipsilateral carotid revascularization, 86 patients (67.2%) saw a decrease in the contralateral artery peak systolic velocity (PSV), while the remaining remained stable or increased. Fifty-four patients had a change in designated stenosis severity in the contralateral artery. Between the carotid endarterectomy and stenting cohorts, there was no significant difference in the proportion of patients whose contralateral velocity decreased (69.4% vs. 61.3%, P = 0.402). Patients with coronary artery disease and diabetes were significantly less likely to experience a decrease in the contralateral artery PSV after ipsilateral intervention (P = 0.018 and P = 0.033). CONCLUSIONS:In patients with bilateral carotid disease, ipsilateral revascularization can change the contralateral artery velocity and perceived disease severity. Most patients were noted to have a decrease in the contralateral artery PSV, although almost one-third either stayed stable or increased. On multivariable analysis, patients with coronary artery disease and diabetes were less likely to see a decrease in the contralateral artery PSV after intervention. Patients who are at risk for artificial elevation of the contralateral artery may warrant a re-evaluation of the contralateral artery after ipsilateral intervention. These patients are potentially better assessed with axial imaging, although further research is needed.

OBJECTIVE:The aim of this study was to investigate the natural history of internal carotid artery (ICA) stenosis progression. METHODS:This single-institution retrospective cohort study analyzed patients diagnosed with ICA stenosis of 50% or greater on duplex ultrasound from 2015 to 2022. Subjects were drawn from our institutional Intersocietal Accreditation Commission-accredited noninterventional vascular laboratory database. Primary outcomes were incidences of disease progression, and stroke or revascularization after index study. Progression was defined as an increase in stenosis classification category. Imaging, demographic, and clinical data was obtained from our institutional electronic medical record via a database mining query. Cases were analyzed at the patient and artery levels, with severity corresponding to the greatest degree of ICA stenosis on index and follow-up studies. RESULTS:Of 577 arteries in 467 patients, mean cohort age was 73.5 ± 8.9 years at the time of the index study, and 45.0% (n = 210) were female. Patients were followed with duplex ultrasound for a mean of 42.2 ± 22.7 months. Of 577 arteries, 65.5% (n = 378) at the index imaging study had moderate (50%-69%) stenosis, 23.7% (n = 137) had severe (70%-99%) stenosis, and 10.7% (n = 62) were occluded. These three groups had significant differences in age, hypertension, hyperlipidemia prevalence, and proportion on best medical therapy. Of the 467-patient cohort, 56.5% (n = 264) were on best medical therapy, defined as smoking cessation, treatment with an antiplatelet agent, statin, and antihypertensive and glycemic agents as indicated. Mean time to progression for affected arteries was 28.0 ± 20.5 months. Of those arteries with nonocclusive disease at diagnosis, 21.3% (n = 123) progressed in their level of stenosis. Older age, diabetes, and a history of vasculitis were associated with stenosis progression, whereas antiplatelet agent use trended towards decreased progression rates. Of the 467 patients, 5.6% (n = 26) developed symptoms; of those, 38.5% (n = 10) had ischemic strokes, 26.9% (n = 7) had hemispheric transient ischemic attacks, 11.5% (n = 3) had amaurosis fugax, and 23.1% (n = 6) had other symptoms. A history of head and neck cancer was positively associated with symptom development. Of 577 affected arteries, 16.6% (n = 96) underwent intervention; 81% (n = 78) of interventions were for asymptomatic disease and 19% (n = 18) were for symptomatic disease. No patient-level factors were associated with risk of intervention. CONCLUSIONS:A significant number of carotid stenosis patients experience progression of disease. Physicians should consider long-term surveillance on all patients with carotid disease, with increased attention paid to those with risk factors for progression, particularly those with diabetes and a history of vasculitis.

OBJECTIVE:Complex endovascular juxta-, para- and suprarenal abdominal aortic aneurysm repair (comEVAR) is frequently accomplished with commercially available fenestrated (FEVAR) devices or off-label use of aortoiliac devices with parallel branch stents (chEVAR). We sought to evaluate the implantable vascular device costs incurred with these procedures as compared with standard Medicare reimbursement to determine the financial viability of comEVAR in the modern era. METHODS:Five geographically distinct institutions with high-volume, complex aortic centers were included. Implantable aortoiliac and branch stent device cost data from 25 consecutive, recent, comEVAR in the treatment of juxta-, para-, and suprarenal aortic aneurysms at each center were analyzed. Cases of rupture, thoracic aneurysms, reinterventions, and physician-modified EVAR were excluded, as were ancillary costs from nonimplantable equipment. Data from all institutions were combined and stratified into an overall cost group and two, individual cost groups: FEVAR or chEVAR. These groups were compared, and each respective group was then compared with weighted Medicare reimbursement for Diagnosis-Related Group codes 268/269. Median device costs were obtained from an independent purchasing consortium of >3000 medical centers, yielding true median cost-to-institution data rather than speculative, administrative projections or estimates. RESULTS:A total of 125 cases were analyzed: 70 FEVAR and 53 chEVAR. Two cases of combined FEVAR/chEVAR were included in total cost analysis, but excluded from direct FEVAR vs chEVAR comparison. Median Medicare reimbursement was calculated as $35,755 per case. Combined average implantable device cost for all analyzed cases was $28,470 per case, or 80% of the median reimbursement ($28,470/$35,755). Average FEVAR device cost per case ($26,499) was significantly lower than average chEVAR cost per case ($32,122; P < .002). Device cost was 74% ($26,499/$35,755) of total reimbursement for FEVAR and 90% ($32,122/$35,755) for chEVAR. CONCLUSIONS:Results from this multi-institutional analysis show that implantable device cost alone represents the vast majority of weighted total Medicare reimbursement per case with comEVAR, and that chEVAR is significantly more costly than FEVAR. Inadequate Medicare reimbursement for these cases puts high-volume, high-complexity aortic centers at a distinct financial disadvantage. In the interest of optimizing patient care, these data suggest a reconsideration of previously established, outdated, Diagnosis-Related Group coding and Medicare reimbursement for comEVAR.

BACKGROUND:Intraoperative dextran infusion has been associated with reduction of an embolic risk in patients undergoing carotid endarterectomy (CEA). Nonetheless, dextran has been associated with adverse reactions, including anaphylaxis, hemorrhage, cardiac, and renal complications. Herein, we aimed to compare the perioperative outcomes of CEA stratified by the use of intraoperative dextran infusion using a large multiinstitutional dataset. METHODS:Patients undergoing CEA between 2008 and 2022 from the Vascular Quality Initiative database were reviewed. Patients were categorized by use of intraoperative dextran infusion, and demographics, procedural data, and in-hospital outcomes were compared. Logistic regression analysis was utilized to adjust for differences in patients while assessing the association between postoperative outcomes and intraoperative infusion of dextran. RESULTS:Of 140,893 patients undergoing CEA, 9,935 (7.1%) patients had intraoperative dextran infusion. Patients with intraoperative dextran infusion were older with lower rates of symptomatic stenosis (24.7% vs. 29.3%; P < 0.001) and preoperative use of antiplatelets, anticoagulants and statins. Additionally, they were more likely to have severe carotid stenosis (>80%; 49% vs. 45%; P < 0.001) and undergo CEA under general anesthesia (96.4% vs. 92.3%; P < 0.001), with a more frequent use of shunt (64.4% vs. 49.5%; P < 0.001). After adjustment, multivariable analysis showed that intraoperative dextran infusion was associated with higher odds of in-hospital major adverse cardiac events (MACE), including myocardial infarction [MI] (odds ratio [OR], 1.76, 95% confidence interval [CI]: 1.34-2.3, P < 0.001), congestive heart failure [CHF] (OR, 2.15, 95% CI: 1.67-2.77, P = 0.001), and hemodynamic instability requiring vasoactive agents (OR, 1.08, 95% CI: 1.03-1.13, P = 0.001). However, it was not associated with decreased odds of stroke (OR, 0.92, 95% CI: 0.74-1.16, P = 0.489) or death (OR, 0.88, 95% CI: 0.58-1.35, P = 0.554). These trends persisted even when stratified by symptomatic status and degree of stenosis. CONCLUSIONS:Intraoperative infusion of dextran was associated with increased odds of MACE, including MI, CHF, and persistent hemodynamic instability, without decreasing the risk of stroke perioperatively. Given these results, judicious use of dextran in patients undergoing CEA is recommended. Furthermore, careful perioperative cardiac management is warranted in select patients receiving intraoperative dextran during CEA.

PURPOSE/OBJECTIVE:Mechanical thrombectomy for the treatment of deep vein thrombosis (DVT) is being increasingly utilized to reduce symptoms and prevent postthrombotic syndrome (PTS), but more data on clinical outcomes are needed. Mechanical thrombectomy was studied in the ClotTriever Outcomes (CLOUT) registry with 6-month full analysis outcomes reported herein. MATERIALS AND METHODS/METHODS:The CLOUT registry is a prospective, all-comer study that enrolled 500 lower extremity DVT patients across 43 US sites treated with mechanical thrombectomy using the ClotTriever System. Core-lab assessed Marder scores and physician-assessed venous patency by duplex ultrasound, PTS assessment using Villalta score, venous symptom severity, pain, and quality of life scores through 6 months were analyzed. Adverse events were identified and independently adjudicated. RESULTS:All-cause mortality at 30 days was 0.9%, and 8.6% of subjects experienced a serious adverse event (SAE) within the first 30 days, 1 of which (0.2%) was device related. SAE rethrombosis/residual thrombus incidence was 4.8% at 30 days and 8.0% at 6 months. Between baseline and 6 months, venous flow increased from 27.2% to 92.5% of limbs (P < 0.0001), and venous compressibility improved from 28.0% to 91.8% (P < 0.0001), while median Villalta scores improved from 9.0 at baseline to 1.0 at 6 months (P < 0.0001). Significant improvements in venous symptom severity, pain, and quality of life were also demonstrated. Outcomes from iliofemoral and isolated femoral-popliteal segments showed similar improvements. CONCLUSION/CONCLUSIONS:Outcomes from the CLOUT study, a large prospective registry for DVT, indicate that mechanical thrombectomy is safe and demonstrates significant improvement in symptoms and health status through 6 months. Level of Evidence 3: Non-randomized controlled cohort/follow-up study.

Patients with coronavirus disease 2019 (COVID-19) present increased risk for ischemic cardiovascular complications up to 1 year after infection. Although the systemic inflammatory response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection likely contributes to this increased cardiovascular risk, whether SARS-CoV-2 directly infects the coronary vasculature and attendant atherosclerotic plaques remains unknown. Here we report that SARS-CoV-2 viral RNA is detectable and replicates in coronary lesions taken at autopsy from severe COVID-19 cases. SARS-CoV-2 targeted plaque macrophages and exhibited a stronger tropism for arterial lesions than adjacent perivascular fat, correlating with macrophage infiltration levels. SARS-CoV-2 entry was increased in cholesterol-loaded primary macrophages and dependent, in part, on neuropilin-1. SARS-CoV-2 induced a robust inflammatory response in cultured macrophages and human atherosclerotic vascular explants with secretion of cytokines known to trigger cardiovascular events. Our data establish that SARS-CoV-2 infects coronary vessels, inducing plaque inflammation that could trigger acute cardiovascular complications and increase the long-term cardiovascular risk.

BACKGROUND:Aberrant subclavian artery (ASA) with or without Kommerell's diverticulum (KD) is a rare anatomic aortic arch anomaly that can cause dysphagia and/or life-threatening rupture. The objective of this study is to compare outcomes of ASA/KD repair in patients with a left versus right aortic arch. METHODS:Using the Vascular Low Frequency Disease Consortium methodology, a retrospective review was performed of patients ≥18 years old with surgical treatment of ASA/KD from 2000 to 2020 at 20 institutions. RESULTS:288 patients with ASA with or without KD were identified; 222 left-sided aortic arch (LAA), and 66 right-sided aortic arch (RAA). Mean age at repair was younger in LAA 54 vs. 58 years (P = 0.06). Patients in RAA were more likely to undergo repair due to symptoms (72.7% vs. 55.9%, P = 0.01), and more likely to present with dysphagia (57.6% vs. 39.1%, P < 0.01). The hybrid open/endovascular approach was the most common repair type in both groups. Rates of intraoperative complications, death within 30 days, return to the operating room, symptom relief and endoleaks were not significantly different. For patients with symptom status follow-up data, in LAA, 61.7% had complete relief, 34.0% had partial relief and 4.3% had no change. In RAA, 60.7% had complete relief, 34.4% had partial relief and 4.9% had no change. CONCLUSIONS:In patients with ASA/KD, RAA patients were less common than LAA, presented more frequently with dysphagia, had symptoms as an indication for intervention, and underwent treatment at a younger age. Open, endovascular and hybrid repair approaches appear equally effective, regardless of arch laterality.