Natural history of internal carotid artery stenosis progression.

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.

The natural history and long-term follow-up of splenic artery aneurysms.

OBJECTIVE: Although splenic artery aneurysms (SAAs) are the most common visceral aneurysm, there is a paucity of literature on the behavior of these entities. The objective of this study was to review the natural history of patients with SAA. METHODS: This single-institution, retrospective analysis studied patients with SAA diagnosed by computed tomography imaging between 2015 and 2019, identified by our institutional radiology database. Imaging, demographic, and clinical data were obtained via the electronic medical record. The growth rate was calculated for patients with radiologic follow-up. RESULTS: The cohort consisted of 853 patients with 890 SAAs, of whom 692 were female (81.2%). There were 37 women (5.3%) of childbearing age (15-50 years). The mean age at diagnosis was 70.9 years (range: 28-100 years). Frequently observed medical comorbidities included hypertension (70.2%), hypercholesterolemia (54.7%), and prior smoking (32.2%). Imaging indications included abdominal pain (37.3%), unrelated follow-up (28.0%), and follow-up of a previously noted visceral artery aneurysm (8.6%). The mean diameter at diagnosis was 13.3 ± 6.3 mm. Anatomic locations included the splenic hilum (36.0%), distal splenic artery (30.3%), midsplenic artery (23.9%), and proximal splenic artery (9.7%). Radiographically, the majority were saccular aneurysms (72.4%) with calcifications (88.5%). One patient (38-year-old woman) was initially diagnosed at the time of rupture of a 25 mm aneurysm; this patient underwent immediate endovascular intervention with no complications. The mean clinical follow-up among 812 patients was 4.1 ± 4.0 years, and the mean radiological follow-up among 514 patients was 3.8 ± 6.8 years. Of the latter, 122 patients (23.7%) experienced growth. Aneurysm growth rates for initial sizes <10 mm (n = 123), 10 to 19 mm (n = 353), 20 to 29 mm (n = 34), and >30 mm (n = 4) were 0.166 mm/y, 0.172 mm/y, 0.383 mm/y, and 0.246 mm/y, respectively. Of the entire cohort, 27 patients (3.2%) eventually underwent intervention (81.5% endovascular), with the most common indications including size/growth criteria (70.4%) and symptom development (18.5%). On multivariate analysis, only prior tobacco use was significantly associated with aneurysm growth (P = .028). CONCLUSIONS: The majority of SAAs in this cohort remained stable in size, with few patients requiring intervention over a mean follow-up of 4 years. Current guidelines recommending treatment of asymptomatic aneurysms >30 mm appear appropriate given their slow progression. Despite societal recommendations for intervention for all SAAs among women of childbearing age, only a minority underwent vascular surgical consultation and intervention in this series, indicating that these recommendations are likely not well known in the general medical community.

Duplex ultrasound and cross-sectional imaging in carotid artery occlusion diagnosis.

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.

Prior authorization requirements in the office-based laboratory setting are administratively inefficient and threaten timeliness of care.

OBJECTIVE: The objective of this study was to investigate the administrative and clinical impacts of prior authorization (PA) processes in the office-based laboratory (OBL) setting. METHODS: This single-institution, retrospective analysis studied all OBL PAs pursued between January 2018 and March 2022. Case, PA, and coding information was obtained from the practice's scheduling database. RESULTS: Over the study period, 1854 OBL cases were scheduled; 8% (n = 146) required PA. Of these, 75% (n = 110) were for lower extremity arterial interventions, 19% (n = 27) were for deep venous interventions, and 6% (n = 9) were for other interventions. Of 146 PAs, 19% (n = 27) were initially denied but 74.1% (n = 7) of these were overturned on appeal. Deep venous procedures were initially denied, at 43.8% (n = 14), more often than were arterial procedures, at 11.8% (n = 13). Of 146 requested procedures, 4% (n = 6) were delayed due to pending PA determination by a mean 14.2 ± 18.3 working days. An additional 6% (n = 8) of procedures were performed in the interest of time before final determination. Of the seven terminally denied procedures, 57% (n = 4) were performed at cost to the practice based on clinical judgment. CONCLUSIONS: Using PA appeals mechanisms, while administratively onerous, resulted in the overturning of most initial denials.

The substantial burden of iatrogenic vascular injury on the vascular surgery workforce at an academic medical center.

OBJECTIVE: Vascular surgeons are often called upon to provide emergent surgical assistance to other specialties for iatrogenic complications, both intraoperatively and in the inpatient setting. The management of iatrogenic vascular injury remains a critical role of the vascular surgeon, especially in the context of the increasing adoption of percutaneous procedures by other specialties. This study aims to characterize consultation timing, management, and outcomes for iatrogenic vascular injuries. METHODS: This study identified patients for whom vascular surgery was consulted for iatrogenic vascular complications from February 1, 2022, to May 12, 2023. Patient information, including demographic information, injury details, and details of any operative intervention, was retrospectively collected from February 1, 2022, to October 13, 2022, and prospectively collected for the remainder of the study period. Analyses were performed with R (version 2022.02.03). RESULTS: There were 87 patients with consultations related to iatrogenic vascular injury. Of these, 42 (46%) were female and the mean age was 59 years (±18 years). The most common consulting services were cardiology (32%), cardiothoracic surgery (26%), general surgery (8%), and neurointerventional radiology (10%). Reasons for consultation included hemorrhage (36%), limb ischemia (36%), and treatment of pseudoaneurysm (23%). A total of 24% of consults were intraoperative, 20% of consults related to extracorporeal membrane oxygenation cannulation, and 16% of consults related to ventricular assist devices including left ventricular assist device and intra-aortic balloon pump. The majority of these consult requests (60%) occurred during evening and night hours (5 PM to 7 AM). Emergent intervention was required in 62% of cases and consisted of primary open surgical repair of arterial injury (54%), endovascular intervention (21%), and open thromboembolectomy (15%). Overall, in-hospital mortality for the patient cohort was 20% and the reintervention rate was 23%, reflecting the underlying complexity of the illness and nature of the vascular injury in this patient group. CONCLUSIONS: Vascular surgeons play an essential role in managing emergent life-threatening hemorrhagic and ischemic iatrogenic vascular complications in the hospitalized setting. The complications require immediate bedside or intraoperative consult and often emergent open surgical or endovascular intervention. Furthermore, many of these require urgent management in the evening or overnight hours, and therefore the high frequency of these events represents a potential significant resource utilization and workforce issue to the vascular surgery workforce.

Dynamic Perioperative Platelet Activity and Cardiovascular Events in Peripheral Artery Disease.

OBJECTIVE: Patients with peripheral artery disease (PAD) undergo lower extremity revascularization (LER) for symptomatic relief or limb salvage. Despite LER, patients remain at increased risk of platelet-mediated complications, such as major adverse cardiac and limb events (MACLE). Platelet activity is associated with cardiovascular events; yet little is known about the dynamic nature of platelet activity over time. We therefore investigated the change in platelet activity over time and its association with long-term cardiovascular risk. METHODS: Patients with PAD undergoing LER were enrolled into the multicenter, prospective Platelet Activity and Cardiovascular Events (PACE) study. Platelet aggregation was assessed by light transmission aggregometry (LTA) to submaximal epinephrine (0.4µ M) immediately prior to LER, and on post-operative day 1 or 2 (POD1) and 30 (POD30). A hyperreactive platelet phenotype was defined as >60% aggregation. Patients were followed longitudinally for MACLE, defined as the composite of death, myocardial infarction, stroke, major lower extremity amputation, or acute limb ischemia leading to reintervention. RESULTS: Among 287 patients undergoing LER, mean age was 70 ± 11 years, 33% were female, 61% were white, and 89% were on baseline antiplatelet therapy. Platelet aggregation to submaximal epinephrine induced a bimodal response; 15.5%, 16.8%, and 16.4% of patients demonstrated a hyperreactive platelet phenotype at baseline, POD1, and POD30, respectively. Platelet aggregation increased by 18.5% (P=0.001) from baseline to POD1, which subsequently returned to baseline at POD30. After a median follow-up of 19 months, MACLE occurred in 165 (57%) patients. After adjustment for demographics, clinical risk factors, procedure type, and antiplatelet therapy, platelet hyperreactivity at POD1 was associated with a significant hazard of long-term MACLE (aHR 4.61, 95% CI 2.08-10.20, P<0.001). CONCLUSION: Among patients with severe PAD, platelet activity increases following LER. Platelet hyperreactivity to submaximal epinephrine on POD1 is associated with long-term MACLE. Platelet activity following LER may represent a modifiable biomarker associated with excess cardiovascular risk.

The Effect of Ipsilateral Carotid Revascularization on Contralateral Carotid Duplex Parameters in Patients with Bilateral Carotid Stenosis.

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.

Short-term outcomes of endovascular management of acute limb ischemia using aspiration mechanical thrombectomy.

OBJECTIVE: Management of acute limb ischemia (ALI) has seen greater utilization of catheter-based interventions over the last two decades. Data on their efficacy is largely based on comparisons of catheter-directed thrombolysis (CDT) and open thrombectomy. During this time, many adjuncts to CDT have emerged with different mechanisms of action, including pharmacomechanical thrombolysis (PMT) and aspiration mechanical thrombectomy (AMT). However, the safety and efficacy of newer adjuncts like AMT have not been well established. This study is a retrospective analysis of the contemporary management of ALI comparing patients treated with aspiration mechanical thrombectomy to patients treated with the more established CDT adjunct, pharmacomechanical thrombolysis. METHODS: Patients undergoing peripheral endovascular intervention for ALI using an adjunctive device were identified through query of the Vascular Quality Initiative (VQI) Peripheral Vascular Intervention (PVI) module from 2014 to 2019. Patients with a nonviable extremity (Rutherford ALI Stage 3), prior history of ipsilateral major amputation, popliteal aneurysm, procedures that were deemed elective (>72 h from admission), procedures that did not utilize an endovascular adjunctive device, and patients without short-term follow-up were all excluded from analysis. The primary outcome was a composite outcome of freedom from major amputation and/or death in the perioperative time period. RESULTS: We identified 528 patients with Rutherford ALI Stage 1 or 2 who were treated with an endovascular adjunct. 433 patients did not undergo aspiration mechanical thrombectomy (no AMT group) and 95 patients did undergo aspiration mechanical thrombectomy (AMT group). The amputation-free survival across all patients was 93.4%. There were significant differences in demographic, comorbidity, and treatment variables between groups (e.g., gender, prior percutaneous coronary intervention (PCI), history of prior peripheral artery disease intervention, and history of prior infra-inguinal PVI), so a propensity score matched analysis was included to account for these group differences. In the propensity score matched analysis, there was no significant difference in major amputation (AMT 7.4% vs no AMT 3.2%, p = 0.13) or death (AMT 95.8% survival vs no AMT 98.4% survival, p = 0.23) with the use of aspiration mechanical thrombectomy. However, there was significantly worse amputation-free survival with the use of aspiration mechanical thrombectomy (AMT 88.4% vs no AMT 95.3%, p = 0.03). On multivariate analysis, prior supra-inguinal bypass (OR 4.85, 1.70-13.84, p = 0.003), Rutherford ALI Stage 2B (OR 3.13, 1.47-6.67, p = 0.003), and aspiration mechanical thrombectomy (OR 2.71, 1.03-7.17, p = 0.05) were associated with the composite outcome. CONCLUSIONS: Short-term amputation-free survival rates of endovascular management of acute limb ischemia are adequate across all modalities. However, aspiration mechanical thrombectomy was associated with significantly worse amputation-free survival compared to other endovascular adjuncts alone (i.e., pharmacomechanical thrombolysis). Severe limb ischemia (Rutherford ALI Stage 2B) and prior supra-inguinal bypass were associated with worse amputation-free survival regardless of the choice of endovascular intervention.

Generative artificial intelligence chatbots may provide appropriate informational responses to common vascular surgery questions by patients.

OBJECTIVES: 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: ChatGPT responses were rated, on average, more accurate than Bard responses (3.08 ± 0.33 vs 2.82 ± 0.40, p < .01). ChatGPT responses were scored, on average, more complete than Bard responses (2.98 ± 0.34 vs 2.62 ± 0.36, p < .01). Most ChatGPT responses (75.0%, n = 18) and almost half of Bard responses (45.8%, n = 11) were unanimously deemed appropriate. Almost one-third of Bard responses (29.2%, n = 7) were deemed inappropriate by at least two reviewers (29.2%), and two Bard responses (8.4%) were considered inappropriate by the majority. The mean Flesch Reading Ease, Flesch-Kincaid Grade Level, and Gunning Fog Index of ChatGPT responses were 29.4 ± 10.8, 14.5 ± 2.2, and 17.7 ± 3.1, respectively, indicating that responses were readable with a post-secondary education. Bard's mean readability scores were 58.9 ± 10.5, 8.2 ± 1.7, and 11.0 ± 2.0, respectively, indicating that responses were readable with a high-school education (p < .0001 for three metrics). ChatGPT's mean response length (332 ± 79 words) was higher than Bard's mean response length (183 ± 53 words, p < .001). There was no difference in the accuracy, completeness, readability, or response length of ChatGPT or Bard between disease domains (p > .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.

Young patients undergoing carotid endarterectomy have increased rates of recurrent disease and late neurological events.

OBJECTIVES: There are few data regarding outcomes of patients with premature cerebrovascular disease (age ≤55 years) who undergo carotid endarterectomy (CEA). The objective of this study was to analyze the demographics, presentation, perioperative and later outcomes of younger patients undergoing CEA. METHODS: The Society for Vascular Surgery Vascular Quality Initiative was queried for CEA cases between 2012 and 2022. Patients were stratified based on age of less than 55 or age greater than 55 years. Primary end points were periprocedural stroke, death, myocardial infarction, and composite outcomes. Secondary end points included restenosis (≥80%) or occlusion, late neurological events and reintervention. RESULTS: Of 120,549 patients undergoing CEA, 7009 (5.5%) were 55 years old or younger (mean age, 51.3 years). Younger patients were more likely to be African American (7.7% vs 4.5%; P < .001), female (45.2% vs 38.9%; P < .001), and active smokers (57.3% vs 24.1%; P < .001). They were less likely than older patients to have hypertension (82.5% vs 89.7%; P < .001), coronary artery disease (25.0% vs 27.3%; P < .001), and congestive heart failure (7.8% vs 11.4%; P < .001). Younger patients were significantly less likely than older patients to be on aspirin, anticoagulation, statins, or beta-blockers, but were more likely to be taking P2Y12 inhibitors (37.2 vs 33.7%; P < .001). Younger patients were more likely to present with symptomatic disease (35.1% vs 27.6%; P < .001) and were more likely to undergo nonelective CEA (19.2% vs 12.8%; P < .001). Younger and older patients had similar rates of perioperative stroke/death (2% vs 2%; P = NS) and postoperative neurological events (1.9% vs 1.8%; P = NS). However, younger patients had lower rates of overall postoperative complications compared with their older counterparts (3.7% vs 4.7%; P < .001). Of these patients, 72.6% had recorded follow-up (mean, 13 months). During follow-up, younger patients were significantly more likely than older patients to experience a late failure, defined as significant restenosis (≥80%) or complete occlusion of the operated artery (2.4% vs 1.5%; P < .001) and were more likely to experience any neurological event (3.1% vs 2.3%; P < .001). Reintervention rates did not significantly differ between the two cohorts. After controlling for covariates using a logistic regression model, age 55 years or younger was independently associated with increased odds of late restenosis or occlusion (odds ratio, 1.591; 95% confidence interval, 1.221-2.073; P < .001) as well as late neurological events (odds ratio, 1.304; 95% confidence interval, 1.079-1.576; P = .006). CONCLUSIONS: Young patients undergoing CEA are more likely to be African American, female, and active smokers. They are more likely to present symptomatically and undergo nonelective CEA. Although perioperative outcomes are similar, younger patients are more likely to experience carotid occlusion or restenosis as well as subsequent neurological events, during a relatively short follow-up period. These data suggest that younger CEA patients may require more diligent follow-up, as well as a continued aggressive approach to medical management of atherosclerosis to prevent future events related to the operated artery, given the particularly aggressive nature of premature atherosclerosis.

Young patients undergoing carotid stenting procedures have an increased rate of procedural failure at 1-year follow-up.

OBJECTIVE: The outcomes of patients with premature cerebrovascular disease (age ≤55 years) who undergo carotid artery stenting are not well-defined. Our study objective was to analyze the outcomes of younger patients undergoing carotid stenting. METHODS: The Society for Vascular Surgery Vascular Quality Initiative was queried for transfemoral carotid artery stenting (TF-CAS) and transcarotid artery revascularization (TCAR) procedures between 2016 and 2020. Patients were stratified based on age ≤55 or >55 years. Primary endpoints were periprocedural stroke, death, myocardial infarction (MI), and composite outcomes. Secondary endpoints included procedural failure (defined as ipsilateral restenosis ≥80% or occlusion) and reintervention rates. RESULTS: Of the 35,802 patients who underwent either TF-CAS or TCAR, 2912 (6.1%) were ≤55 years. Younger patients were less likely than older patients to have coronary disease (30.5% vs 50.2%; P < .001), diabetes (31.5% vs 37.9%; P < .001), and hypertension (71.8% vs 89.8%; P < .001), but were more likely to be female (45% vs 35.4%; P < .001) and active smokers (50.9% vs 24.0%; P < .001) Younger patients were also more likely to have had a prior transient ischemic attack or stroke than older patients (70.7% vs 56.9%; P < .001). TF-CAS was more frequently performed in younger patients (79.7% vs 55.4%; P < .001). In the periprocedural period, younger patients were less likely to have a MI than older patients (0.3% vs 0.7%; P < .001), but there was no significant difference in the rates of periprocedural stroke (1.5% vs 2.0%; P = .173) and composite outcomes of stroke/death (2.6% vs 2.7%; P = .686) and stroke/death/MI (2.9% vs 3.2%; P = .353) between our two cohorts. The mean follow-up was 12 months regardless of age. During follow-up, younger patients were significantly more likely to experience significant (≥80%) restenosis or occlusion (4.7% vs 2.3%; P = .001) and to undergo reintervention (3.3% vs 1.7%; P < .001). However, there was no statistical difference in the frequency of late strokes between younger and older patients (3.8% vs 3.2%; P = .129). CONCLUSIONS: Patients with premature cerebrovascular disease undergoing carotid artery stenting are more likely to be African American, female, and active smokers than their older counterparts. Young patients are also more likely to present symptomatically. Although periprocedural outcomes are similar, younger patients have higher rates of procedural failure (significant restenosis or occlusion) and reintervention at 1-year follow-up. However, the clinical implication of late procedural failure is unknown, given that we found no significant difference in the rate of stroke at follow-up. Until further longitudinal studies are completed, clinicians should carefully consider the indications for carotid stenting in patients with premature cerebrovascular disease, and those who do undergo stenting may require close follow-up.

Natural history of renal artery aneurysms.

OBJECTIVE: The existing renal artery aneurysm (RAA) literature is largely composed of reports of patients who underwent intervention. The objective of this study was to review the natural history of RAA. METHODS: This single-institution retrospective analysis studied all patients with RAA diagnosed by computed tomography imaging between 2015 and 2019, identified by our institutional radiology database. Imaging, demographic, and clinical data were obtained via the electronic medical record. He growth rate was calculated for all patients with radiological follow-up. RESULTS: The cohort consists of 331 patients with 338 RAAs. Most patients were female (61.3%), with 11 (3.3%) of childbearing age. The mean age at diagnosis was 71.5 years (range, 24-99 years). Medical comorbidities included hypertension (73.7%), prior smoking (34.4%), and connective tissue disease (3.9%). Imaging indications included abdominal pain (33.5%), unrelated follow-up (29.6%), and follow-up of an RAA initially diagnosed before the study period (10.7%). Right RAA (61.9%) was more common than left (35.1%); 3% of patients had bilateral RAA. The mean diameter at diagnosis was 12.9 ± 5.9 mm. Size distribution included lesions measuring less than <15 mm (69.9%), 15 to 25 mm (27.1%), and more than 25 mm (3.0%). Anatomic locations included the distal RA (26.7%), renal hilum (42.4%), and mid-RA (13.1%). The majority were true aneurysms (98%); of these, 72.3% were fusiform and 27.7% were saccular. Additional characteristics included calcification (82.2%), thrombus (15.9%), and dissection (0.9%). Associated findings included aortic atherosclerosis (65.6%), additional visceral aneurysms (7.3%), and abdominal aortic aneurysm (5.7%). The mean clinical follow-up among 281 patients was 41.0 ± 24.0 months. The mean radiological follow-up among 137 patients was 26.0 ± 21.4 months. Of these, 43 patients (31.4%) experienced growth, with mean growth rate of 0.23 ± 4.7 mm/year; the remainder remained stable in size. Eight patients eventually underwent intervention (5 endovascular), with the most common indications including size criteria (4/8) and symptom development (3/8). No patient developed rupture. On multivariate analysis, obesity (P = .04) was significantly associated with growth. An initial diameter of more than 25 mm was significantly associated with subsequent intervention (P = .006), but was not significantly associated with growth. Four of five RAAs with an initial diameter 30 mm or greater did not undergo intervention. The mean clinical follow-up for these patients was 24 months; none developed rupture and two remained stable in size. CONCLUSIONS: This large institutional cohort found that the majority of RAAs remained stable in size, with few patients meeting indications for repair based on societal guidelines. Current guidelines recommending intervention for asymptomatic aneurysms more than 30 mm seem to be appropriate given their slow progression.

The Natural History of Carotid Artery Occlusions Diagnosed on Duplex Ultrasound.

BACKGROUND: There is a paucity of literature on the natural history of extracranial carotid artery occlusion (CAO). This study reviews the natural history of this patient cohort. METHODS: This single-institution retrospective analysis studied patients with CAO diagnosed by duplex ultrasound between 2010 and 2021. Patients were identified by searching our office-based Intersocietal Accreditation Commission accredited vascular laboratory database. Imaging and clinical data were obtained via our institutional electronic medical record. Outcomes of interest included ipsilateral stroke, attributable neurologic symptoms, and ipsilateral intervention after diagnosis. RESULTS: The full duplex database consisted of 5,523 patients who underwent carotid artery duplex examination during the study period. The CAO cohort consisted of 139 patients; incidence of CAO was 2.5%. Mean age at diagnosis was 69.7 years; 31.4% were female. Hypertension (72.7%), hyperlipidemia (64.7%), and prior smoking (43.9%) were the most common comorbid conditions. Of the CAO cohort, 61.3% (n = 85) of patients were asymptomatic at diagnosis; 38.8% (n = 54) were diagnosed after a stroke or transient ischemic attack occurring within 6 months prior to diagnosis, with 21.6% occurring ipsilateral to the CAO and 10.1% occurring contralateral to the CAO. 7.2% (n = 10) had unclear symptoms or laterality at presentation. Of the CAO cohort, 95 patients (68.3%) had duplex imaging follow-up (mean 42.7 ± 31.3 months). Of those with follow-up studies, 7 patients (5.0%) developed subsequent stroke ipsilateral to the CAO with mean occurrence 27.8 ± 39.0 months postdiagnosis. In addition, 5 patients (3.6%) developed other related symptoms, including global hypoperfusion (2.4%) and transient ischemic attack (1.2%). Of those, 95 patients with follow-up duplex ultrasound imaging, 6 (4.3%) underwent eventual ipsilateral intervention, including carotid endarterectomy (n = 4), transfemoral carotid artery stent (n = 1), and carotid bypass (n = 1), with mean occurrence 17.7 ± 23.7 months postdiagnosis. The aggregate rate of ipsilateral cerebrovascular accident, attributable neurologic symptoms, or ipsilateral intervention was 11.5%. Of 95 patients with follow-up duplex ultrasound imaging, 5 underwent subsequent duplex studies demonstrating ipsilateral patency, resulting in a 5.3% discrepancy rate between sequential duplex studies. All 6 patients undergoing intervention received periprocedural cross-sectional imaging (magnetic resonance angiography or computed tomography angiography). In 5 of these 6 patients, cross-sectional demonstrated severe stenosis rather than CAO, disputing prior duplex ultrasound findings. CONCLUSIONS: In this large, institutional cohort of patients with a CAO diagnosis on duplex ultrasound, a clinically meaningful subset of patients experienced cerebrovascular accident, related symptoms, or intervention. We also found a notable rate of temporal duplex discrepancies among patients with CAO diagnoses and discrepancies between CAO diagnosis per duplex ultrasound and findings on cross-sectional imaging for those patients who underwent intervention. These results suggest that use of a single duplex ultrasound as a sole diagnostic tool in CAO may not be sufficient and that physicians should consider close duplex ultrasound surveillance of these patients, potentially in conjunction with additional confirmatory imaging modalities. Further investigation into optimal workup and surveillance protocols for CAO is needed.

Abdominal aortic aneurysm neck dilatation and sac remodeling in fenestrated compared to standard endovascular aortic repair.

OBJECTIVE: Contemporary commercially available endovascular devices for the treatment of abdominal aortic aneurysm (AAA) include standard endovascular aortic repair (sEVAR) or fenestrated EVAR (fEVAR) endografts. However, aortic neck dilatation (AND) can occur in nearly 25% of patients following EVAR, resulting in loss of proximal seal with risk of aortic rupture. AND has not been well characterized in fEVAR, and direct comparisons studying AND between fEVAR and sEVAR have not been performed. This study aims to analyze AND in the infrarenal and suprarenal aortic segments, including seal zone, and quantify sac regression following fEVAR implantation compared to sEVAR. METHOD: A retrospective review of prospectively collected data on 20 consecutive fEVAR patients (Cook Zenith® Fenestrated) and 20 sEVAR (Cook Zenith®) patients was performed. Demographic data, anatomic characteristics, procedural details, and clinical outcome were analyzed. Pre-operative, post-operative (1 month), and longest follow-up CT scan at an average of 29.3 months for fEVAR and 29.8 months for sEVAR were analyzed using a dedicated 3D workstation (iNtuition, TeraRecon Inc, Foster City, California). Abdominal aortic aneurysm neck diameter was measured in 5 mm increments, ranging from 20 mm above to 20 mm below the lowest renal artery. Sub-analysis comparing the fEVAR to the sEVAR group at 12 months and at greater than 30 months was performed. Standard statistical analysis was done. RESULTS: Demographic characteristics did not differ significantly between the two cohorts. The fEVAR group had a larger mean aortic diameter at the lowest renal artery, shorter infrarenal aortic neck length, increased prevalence of nonparallel neck shape, and longer AAA length. On follow-up imaging, the suprarenal aortic segment dilated significantly more at all locations in the fEVAR cohort, whereas the infrarenal aortic neck segment dilated significantly less compared to the sEVAR group. Compared to the sEVAR cohort, the fEVAR patients demonstrated significantly greater positive sac remodeling as evident by more sac diameter regression, and elongation of distance measured from the celiac axis to the most cephalad margin of the sac. Device migration, endoleak occurrence, re-intervention rate, and mortalities were similar in both groups. CONCLUSION: Compared to sEVAR, patients undergoing fEVAR had greater extent of suprarenal AND, consistent with a more diseased native proximal aorta. However, the infrarenal neck, which is shorter and also more diseased in fEVAR patients, appears more stable in the post-operative period as compared to sEVAR. Moreover, the fEVAR cohort had significantly greater sac shrinkage and improved aortic remodeling. The suprarenal seal zone in fEVAR may result in a previously undescribed increased level of protection against infrarenal neck dilatation. We hypothesize that the resultant decreased endotension conferred by better seal zone may be responsible for a more dramatic sac shrinkage in fEVAR.

Response to clopidogrel in patients undergoing lower extremity revascularization.

OBJECTIVES: Clopidogrel is effective at decreasing cardiovascular events in patients with peripheral artery disease (PAD); however, its effect on limb outcomes are less known. This study investigated the variability in response to clopidogrel and its relationship with clinical limb outcomes. METHODS: Three hundred subjects were enrolled in the Platelet Activity and Cardiovascular Events (PACE) study prior to lower extremity revascularization, of whom 104 were on clopidogrel. Light transmission platelet aggregation was measured in response to ADP 2 µm immediately prior to revascularization. Patients were followed longitudinally for a median follow-up of 18 months. The primary endpoint was major adverse limb events (MALE) defined by major amputation or reoperation of the affected limb. Patients were stratified into groups according to percent ADP-induced aggregation. Poor response to clopidogrel was defined by >50% aggregation. RESULTS: Overall, the median age was 70 (63, 76) and 35.6% were female. Twenty-nine (27.9%) patients experienced MALE during their follow-up. Median aggregation to ADP 2 µ m was 22.5% (Q1-Q3: 10%, 50%) and 27 subjects (26%) were clopidogrel poor responders. Baseline aggregation was higher in subjects who went on to develop a MALE than those without MALE (43% vs 20%, p = .017). Subjects with aggregation > median (22.5%) were more likely to experience MALE than aggregation < median (38.5% vs 17.3%, p = .029). After multivariable adjustment for age, sex, race/ethnicity, BMI, diabetes, coronary artery disease, and aspirin use, aggregation > median was associated with MALE (adjusted HR [aHR] 2.67, 95% CI 1.18-6.01, p = .018). When stratified by established cut-offs for responsiveness to clopidogrel (50% aggregation), poor responders were more likely to experience MALE than normal responders (44.4% vs 22.1%, aHR 2.18, 95% CI 1.00-4.78, p = .051). CONCLUSIONS: Among patients undergoing lower extremity revascularization on clopidogrel, higher baseline percent aggregation is associated with increased risk for major adverse limb events.

Outcomes of transfemoral carotid artery stenting and transcarotid artery revascularization for restenosis after prior ipsilateral carotid endarterectomy.

OBJECTIVE: Restenosis after carotid endarterectomy (CEA) poses unique therapeutic challenges, with no specific guidelines available on the operative approach. Traditionally, transfemoral carotid artery stenting (TfCAS) has been regarded as the preferred approach to treating restenosis after CEA. Recently, transcarotid artery revascularization with a flow-reversal neuroprotection system (TCAR) has gained popularity as an effective alternative treatment modality for de novo carotid artery stenosis. The aim of the present study was to compare the contemporary perioperative outcomes of TfCAS and TCAR in patients with prior ipsilateral CEA. METHODS: The Vascular Quality Initiative database was reviewed for patients who had undergone TfCAS and TCAR for restenosis after prior ipsilateral CEA between January 2016 and August 2020. The primary outcome was the 30-day composite outcome of stroke and death. The secondary outcomes included 30-day stroke, transient ischemic attack (TIA), myocardial infarction (MI), death, and composite 30-day outcomes of stroke, death, and TIA, stroke and TIA, and stroke, death, and MI. Multivariable logistic regression models were used to evaluate the outcomes of interest after adjustment for potential confounders and baseline differences between cohorts. RESULTS: Of 3508 patients, 1834 and 1674 had undergone TfCAS and TCAR, respectively. The TCAR cohort was older (mean age, 71.6 years vs 70.2 years; P < .001) and less likely to be symptomatic (27% vs 46%; P < .001), with a greater proportion taking aspirin (92% vs 88%; P = .001), a P2Y12 inhibitor (89% vs 80%; P < .001), and a statin (91% vs 87%; P = .002) compared with the TfCAS cohort. Perioperatively, the TCAR cohort had had lower 30-day composite outcomes of stroke/death (1.6% vs 2.7%; P = .025), stroke/death/TIA (1.8% vs 3.3%; P = .004), and stroke/death/MI (2.1% vs 3.2%; P = .048), primarily driven by lower rates of stroke (1.3% vs 2.3%; P = .031) and TIA (0.2% vs 0.7%; P = .031). Among asymptomatic patients, the incidence of stroke (0.6% vs 1.4%; P = .042) and the composite of stroke/TIA (0.8% vs 1.8%; P = .036) was significantly lower after TCAR than TfCAS, and TCAR was associated with a lower incidence of TIA (0% vs 1%; P = .038) among symptomatic patients. On adjusted analysis, the TCAR cohort had lower odds of TIA (adjusted odds ratio, 0.17; 95% confidence interval, 0.04-0.74; P = .019). CONCLUSIONS: Among patients undergoing carotid revascularization for restenosis after prior ipsilateral CEA, TCAR was associated with decreased odds of 30-day TIA compared with TfCAS. However, the two treatment approaches were similarly safe in terms of the remaining perioperative outcomes, including stroke and death and stroke, death, and MI. Our results support the safety and efficacy of TCAR in this subset of patients deemed at high risk of reintervention.

Severity of stenosis in symptomatic patients undergoing carotid interventions might influence perioperative neurologic events.

OBJECTIVE: The carotid artery plaque burden, indirectly measured by the degree of stenosis, quantifies a patient's future embolic risk. In natural history studies, patients with moderate degrees of stenosis have had a lower stroke risk than those with severe stenosis. However, patients with symptomatic carotid stenosis who have experienced transient ischemic attack (TIA) or stroke were found to have both moderate and severe degrees of stenosis. We examined the association of carotid artery stenosis severity with the outcomes for symptomatic patients who had undergone carotid intervention, including carotid endarterectomy (CEA), transfemoral carotid artery stenting (TFCAS), and transcervical carotid artery revascularization (TCAR). METHODS: The Society for Vascular Surgery Vascular Quality Initiative database was queried for all patients who had undergone TFCAS, CEA, or TCAR between 2003 and 2020. The patients were stratified into two groups according to stenosis severity-nonsevere (0%-69%) and severe (≥70%). The primary end point was periprocedural neurologic events (stroke and TIA). The secondary end points were periprocedural death, myocardial infarction (MI), and the composite outcomes of stroke/death and stroke/death/MI in accordance with the reporting standards for carotid intervention. RESULTS: Of the 29,614 included symptomatic patients, 5296 (17.9%) had undergone TCAR, 7844 (26.5%) TFCAS, and 16,474 (55.6%) CEA for symptomatic carotid artery stenosis. In the CEA cohort, the neurologic event rate was significantly lower for the patients with severe stenosis than for those with nonsevere stenosis (2.6% vs 3.2%; P = .024). In the TCAR cohort, the periprocedural neurologic even rate was lower for those with severe stenosis than for those with nonsevere stenosis (3% vs 4.3%; P = .033). No similar difference was noted for the TFCAS cohort, with a periprocedural neurologic event rate of 3.8% in the severe group vs 3.5% in the nonsevere group (P = .518). On multivariable analysis, severe stenosis was associated with significantly decreased odds of postprocedural neurologic events after CEA (odds ratio, 0.75; 95% confidence interval, 0.6-0.92; P = .007) and TCAR (odds ratio, 0.83; 95% confidence interval, 0.69-0.99; P = .039) but not after TFCAS. CONCLUSIONS: Severe carotid stenosis, in contrast to more moderate stenosis degrees, was associated with decreased rates of periprocedural stroke and TIA in symptomatic patients undergoing TCAR and CEA but not TFCAS. The finding of increased rates of periprocedural neurologic events in symptomatic patients with lesser degrees of stenosis undergoing TCAR and CEA warrants further evaluation with a particular focus on plaque morphology and brain physiology and their inherent risks with carotid revascularization procedures.

Midterm and Long-Term Outcomes following Dedicated Endovenous Nitinol Stent Placement for Symptomatic Iliofemoral Venous Obstruction: Three- to 5-Year Results of the VIRTUS Study.

PURPOSE: To assess the midterm patency and long-term safety of placement of a dedicated venous stent (Vici Venous Stent System) for the treatment of venous lesions of the iliofemoral outflow tract. MATERIALS AND METHODS: Patients with unilateral obstructive disease of the iliofemoral veins and a Clinical, Etiological, Anatomical, Pathophysiological class of 3 or higher or a Venous Clinical Severity Score of 2 or greater were enrolled in this prospective, multicenter, single-arm study at 23 sites in the United States and Europe. The patients were followed up for 36 months after the index procedure for the assessment of patency and up to 60 months for the assessment of safety. The clinical outcomes in 11 patients with a stent fracture were assessed. RESULTS: A total of 200 patients enrolled in 2 cohorts (ie, feasibility cohort, n = 30; pivotal cohort, n = 170) were combined for this analysis. The overall 36-month primary patency rate was 71.7% (86/120), and the 36-month primary patency rate was 96.4% (27/28) for the nonthrombotic group and 64.1% (59/92) for the postthrombotic group. The freedom from major adverse events was 81.2% (53/65) through 60 months. The 60-month Kaplan-Meier estimate of freedom from target vessel revascularization (TVR) was 84.3%. In 9 of the 11 patients who had a stent fracture (1 patient with nonthrombotic etiology and 10 patients with postthrombotic etiology) identified at 12 months, the stents extended into the common femoral vein. The TVR rates and clinical outcomes were similar between patients with and without a stent fracture. CONCLUSIONS: The results of the VIRTUS study demonstrated good midterm patency and long-term safety following the placement of a dedicated venous stent for iliofemoral obstruction.

Closed incision negative pressure wound therapy may decrease wound complications in major lower extremity amputations.

OBJECTIVE: Wound complications after major lower extremity amputations (LEAs) are a cause of significant morbidity in vascular surgery patients. Recent publications have demonstrated the efficacy of the closed incision negative pressure dressing at preventing surgical site infections (SSIs); however, there are few data on its use in major LEAs. This study sought to assess if closed incision negative pressure wound therapy (NPWT) would decrease the risk of complications as compared with a standard dressing in patients with peripheral vascular disease undergoing major LEA. METHODS: Fifty-four consecutive patient limbs with a history of peripheral arterial disease underwent below-knee or above-knee amputations. This was a retrospective review of a prospectively maintained database from January 2018 to December 2019, and it included 23 amputations in the NPWT group and 31 amputations in the standard dressing group. NPWT using the PREVENA system was applied intraoperatively at the discretion of the operating surgeon and removed 5 to 7 days postoperatively. The standard group received a nonadherent dressing with an overlying compression dressing. Amputation incisions were assessed and wound complications were recorded. Student's t-test and two-sample proportion z-test were used for statistical analysis. A P value of less than .05 was considered statistically significant. RESULTS: For comorbidities, there was a higher incidence of tobacco use in the NPWT as compared with the standard group (44% vs 13%; P = .011), as well as trends toward increased prior amputations, anemia, hyperlipidemia, and chronic obstructive pulmonary disorder in the NPWT group. For risk factors, there were more dirty wounds in the NPWT as compared with the standard group (52% vs 26%; P = .046). For outcomes, there were fewer wound complications in the NPWT as compared with the standard group (13% vs 39%; P = .037). The types of wound-related complications in the NPWT group included one wound dehiscence with a deep SSI, one superficial SSI, and one incision line necrosis. In the standard group, there were four wound dehiscences with deep SSI, three superficial SSIs, four incision line necroses, and one stump hematoma. The rates of perioperative mortality and amputation revision did not differ significantly between the NPWT and the standard groups (3% vs 4% and 4.3% vs 10%, respectively). CONCLUSIONS: Closed incision NPWT may decrease the incidence of wound complications in vascular patients undergoing major LEA. This held true even among a population that was potentially at higher risk. This therapy may be considered for use in lower extremity major amputations.

Endovascular treatment of popliteal artery aneurysms has comparable long-term outcomes to open repair with shorter lengths of stay.

OBJECTIVE: During the past two decades, the treatment of popliteal artery aneurysms (PAAs) has undergone a transformation. Although open surgical repair (OR) has remained the reference standard for treatment, endovascular repair (ER) has become an attractive alternative for select patient populations. The objective of the present study was to compare the outcomes of OR vs ER of PAAs at a single institution. METHODS: We performed a retrospective review of the medical records for all patients who had undergone repair for PAAs from 1998 to 2017. The baseline patient, anatomic, and operative characteristics and outcomes were compared between the OR and ER cohorts. Intervention and treatment were at the discretion of the surgeon. RESULTS: From 1998 to 2017, 64 patients had undergone repair of 73 PAAs at our tertiary care center. Of the 69 patients (73 PAAs), 29 (33 PAAs) had undergone OR and 35 (40 PAAs) had undergone ER. When comparing the two cohorts, no statistically significant differences were found in the demographic characteristics such as age, gender, or number of runoff vessels. Significantly more patients in the ER group (n = 21; 53%) than in the OR group (n = 7; 21%) had had hyperlipidemia (P = .008) and a previous carotid intervention (6% vs 0%; P = .029). Overall, the presence of symptoms was similar between the two groups. However, the OR group had a significantly higher number of patients who had presented with acute ischemia (P = .01). The length of stay was significantly shorter for the ER cohort (mean, 1.8 days; range, 1-11 days) than for the OR group (mean, 5.4 days; range, 2-13 days; P < .0001). No significant difference was found in the primary or secondary patency rates between the two groups. In the ER group, good runoff (two or more vessels) was a positive predictor for primary patency at 1 year (odds ratio, 3.36; 95% confidence interval, 1.0-11.25). However, it was not in the OR group. Postoperative single and/or dual antiplatelet therapy did not affect primary patency in either cohort. CONCLUSIONS: The results of our study have demonstrated that ER of PAAs is a safe and durable option with patency rates comparable to those with OR and a decreased length of stay, with good runoff a positive predictor for primary patency in the ER cohort.