Preoperative COVID-19 Vaccination is Associated with Decreased Perioperative Mortality after Major Vascular Surgery.

OBJECTIVE: The objective of this study was to examine the effect of corona virus 2019 (COVID-19) vaccination on perioperative outcomes after major vascular surgery. BACKGROUND DATA: COVID-19 vaccination is associated with decreased mortality in patients undergoing various surgical procedures. However, the effect of vaccination on perioperative mortality after major vascular surgery is unknown. METHODS: This is a multicenter retrospective study of patients who underwent major vascular surgery between December 2021 through August 2023. The primary outcome was all-cause mortality within 30 days of index operation or prior to hospital discharge. Multivariable models were used to examine the association between vaccination status and the primary outcome. RESULTS: Of the total 85,424 patients included, 19161 (22.4%) were unvaccinated. Unvaccinated patients were younger compared to vaccinated patients (mean age 68.44 +/- 10.37 y vs 72.11 +/- 9.20 y, P <0.001) and less likely to have comorbid conditions, including hypertension, congestive heart failure, chronic obstructive pulmonary disease, and dialysis. After risk factor adjustment, vaccination was associated with decreased mortality (OR 0.7, 95% CI 0.62 - 0.81, P <0.0001). Stratification by procedure type demonstrated that vaccinated patients had decreased odds of mortality after open AAA (OR 0.6, 95% CI 0.42-0.97, P =0.03), EVAR (OR 0.6, 95% CI 0.43-0.83, p 0.002), CAS (OR 0.7, 95% CI 0.51-0.88, P =0.004) and infra-inguinal lower extremity bypass (OR 0.7, 95% CI 0.48-0.96, P =0.03). CONCLUSIONS: COVID-19 vaccination is associated with reduced perioperative mortality in patients undergoing vascular surgery. This association is most pronounced for patients undergoing aortic aneurysm repair, carotid stenting and infrainguinal bypass.

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.

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.

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.

Outcomes and predictors of amputation-free survival in patients undergoing below-knee popliteal-distal bypass.

OBJECTIVE: The infrageniculate popliteal artery is a potential source for inflow in lower extremity bypass surgery in patients with isolated tibial artery disease. The objective of our study was to assess the short- and long-term outcomes of popliteal-distal bypasses using data from the Vascular Quality Initiative (VQI). METHODS: The VQI registry was queried between 2003 and 2021 for patients undergoing surgical revascularizations with the below-knee popliteal artery serving as inflow. Demographics, comorbidities, intraoperative characteristics, and postoperative complications were analyzed. Kaplan-Meier models were used to estimate amputation-free survival, survival, and freedom from amputation. Cox regression analysis was conducted to determine factors associated with major amputation or death. RESULTS: A total of 1884 procedures were analyzed. The mean age of the included patients was 67.7 years. The most frequently observed preoperative comorbidities included insulin-dependent diabetes (52.3%), coronary disease (32.4%), and end-stage renal disease (14.4%). Of all the patients, 670 (35.6%) had a history of ipsilateral endovascular intervention. The procedures were performed for a variety of indications, including tissue loss (84.3%), rest pain (10.9%), and claudication (4.8%). Intraoperatively, the outflow targets were the dorsalis pedis (31.4%), the posterior tibial (24.4%), and the anterior tibial arteries (15.6%). Vein conduit was used in 92.1% of cases. The rate of perioperative myocardial infarction (MI) was 2.4%, and the 30-day mortality was 1.9%. The median length of follow up was 371 days. Amputation-free survival was found to be 85.6% (95% confidence interval [CI], 84.0%-87.2%) at 6 months and 78.6% (95% CI, 76.6%-80.4%) at 12 months. Survival was found to be 93.4% (95% CI, 92.2%-94.5%) at 6 months and 88.6% (95% CI, 87.1%-90.0%) at 12 months. Freedom from amputation was found to be 92.0% (95% CI, 90.7%-93.3%) at 6 months and 89.0% (95% CI, 87.3%-90.4%) at 12 months. Cox regression analysis demonstrated that age greater than 65 years, congestive heart failure, coronary artery disease, and end-stage renal disease were associated with a higher risk of major amputation or death (P < .05). CONCLUSIONS: Below-knee popliteal-distal bypass is a safe and effective approach to treat severe tibial vessel occlusive disease in this challenging patient cohort. Patients exhibited low perioperative complication rates and good amputation-free survival at 1 year.

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.

A registry-based study of paclitaxel drug-coated balloon angioplasty for the treatment of in-stent restenosis of the femoral-popliteal artery.

OBJECTIVE: The aim of this study was to report the results of a prospective, single-arm, registry-based study assessing the safety and performance of a paclitaxel drug-coated balloon (DCB) for the treatment of superficial femoral artery (SFA) or popliteal artery in-stent restenosis (ISR) in a United States population. METHODS: We conducted a prospective, non-randomized, multi-center, single-arm, post-market registry of the IN.PACT Admiral DCB for the treatment of ISR lesions in the SFA or popliteal artery at 43 sites within the Society for Vascular Surgery (SVS) Vascular Quality Initiative (VQI) Registry from December 2016 to January 2020. Clinical outcomes were assessed at 12, 24, and 36 months. The primary endpoint was target lesion revascularization at 12 months. Secondary endpoints included technical success, target vessel revascularization, major limb amputation, and all-cause mortality. Results are presented as survival probabilities based on Kaplan-Meier survival estimates. RESULTS: Patients (N = 300) were 58% male, with a mean age of 68 ± 10 years. Diabetes was present in 56%, 80% presented with claudication, and 20% with rest pain. Lesions included ISR of the SFA in 68%, SFA-popliteal in 26%, and popliteal arteries in 7%. The mean lesion length was 17.8 ± 11.8 cm. Lesions were categorized as occlusions in 43% (mean occluded length, 16 ± 10 cm). TASC type was A (17%), B (29%), C (38%), and D (15%). Technical success was 99%. Re-stenting was performed in 5% and thrombolysis in 0.6% of patients. Kaplan-Meier estimates for freedom from target lesion revascularization were 90%, 72%, and 62% at 12, 24, and 36 months. Freedom from target vessel revascularization was 88%, 68%, and 59% and freedom from major target limb amputation was 99.6%, 98.9%, and 98.9%, respectively, at 12, 24, and 36 months. Survival was 95%, 89%, and 85% at 12, 24, and 36 months. CONCLUSIONS: This post-market registry-based study shows promising results in treating femoral-popliteal ISR with paclitaxel DCB in comparison to the results of plain balloon angioplasty reported in the literature. These results demonstrate the ability of the SVS VQI to conduct post-market evaluation of peripheral devices in partnership with industry and federal regulators.

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.

Supra-Inguinal Inflow for Distal Bypasses Have Acceptable Patency and Limb Salvage Rates.

BACKGROUND: There is a paucity of data evaluating outcomes of lower extremity bypass (LEB) using supra-inguinal inflow for revascularization of infra-inguinal vessels. The purpose of this study is to report outcomes after LEB originating from aortoiliac arteries to infra-femoral targets. METHODS: The Vascular Quality Initiative database (2003-2020) was queried for patients undergoing LEB from the aortoiliac arteries to the popliteal and tibial arteries. Patients were stratified into 3 cohorts based on outflow targets (above-knee [AK] popliteal, below-knee [BK] popliteal, and tibial arteries). Perioperative and 1-year outcomes including primary patency, amputation-free survival (AFS), and major adverse limb events (MALEs) were compared. A Cox proportional hazards model was used to estimate the independent prognostic factors of outcomes. RESULTS: Of 403 LEBs, 389 (96.5%) originated from the external iliac artery, while the remaining used the aorta or common iliac artery as inflow. In terms of the distal target, the AK popliteal was used in 116 (28.8%), the BK popliteal in 151 (27.5%), and tibial vessels in 136 (43.7%) cases. BK popliteal and tibial bypasses, compared to AK popliteal bypasses, were more commonly performed in patients with chronic limb-threatening ischemia (69.5% and 69.9% vs. 48.3%; P < 0.001). Vein conduit was more often used for tibial bypass than for AK and BK popliteal bypasses (46.3% vs. 21.9% and 16.3%; P < 0.001). In the perioperative period, BK popliteal and tibial bypass patients had higher reoperation rates (16.9% and 13.2% vs. 5.2%; P = 0.02) and lower primary patency (89.4% and 89% vs. 95.7%; P = 0.04) than AK bypass patients. At 1 year, compared with AK popliteal bypasses, BK and tibial bypasses demonstrated lower primary patency (81.9% vs. 56.7% vs. 52.4%, P < 0.001) and freedom from MALE (77.6% vs. 70.2% vs. 63.1%, P = 0.04), although AFS was not significantly different (89.7% vs. 90.6% vs. 83.8%, P = 0.19).On multivariable analysis, compared with AK popliteal bypasses, tibial bypasses were independently associated with increased loss of primary patency (hazard ratio 1.9, 95% confidence interval, 1.03-3.51, P = 0.04). Subanalysis of patients with chronic limb-threatening ischemia demonstrated significantly higher primary patency in the AK popliteal cohort at discharge and 1 year, but no difference in AFS or freedom from MALE between the cohorts at follow-up. CONCLUSIONS: LEB with supra-inguinal inflow appear to have acceptable rates of 1-year patency and limb salvage in patients at high risk of bypass failure. Tibial outflow target was independently associated with worse primary patency but not with MALE or AFS.

Optimal medical therapy is lacking in patients undergoing intervention for symptomatic carotid artery stenosis and protects against larger areas of cerebral infarction.

OBJECTIVES: Carotid interventions are indicated for both patients with symptomatic and a subset of patients with severe asymptomatic carotid artery stenosis (CAS). Symptomatic CAS accounts for up to 12%-25% of overall carotid interventions, but predictors of symptomatic presentation remain poorly defined. The aim of this study was to identify factors associated with symptomatic CAS in our patient population. METHODS: Between January 2015 and February 2022, an institutional retrospective cohort study of prospectively collected data on patients undergoing interventions for CAS was performed. Procedures included carotid endarterectomy (CEA), transcarotid artery revascularization (TCAR), and transfemoral carotid artery stenting (TF-CAS). Demographic data, comorbidities, procedural details, and anatomic features from various imaging modalities were collected. Comparisons were made between symptomatic (symptoms within the prior 6 months) and asymptomatic patients. RESULTS: During the study period, 279 patients who underwent intervention for symptomatic CAS were paired with a randomly selected cohort of 300 patients who underwent intervention for asymptomatic CAS from a total patient cohort of 1143 patients undergoing interventions for asymptomatic CAS. Demographic data did not differ between groups. Patients with symptomatic CAS more frequently had prior TIA/stroke (>6 months remote to the current event), but less frequently had coronary artery disease or chronic kidney disease and were less likely to receive adequate medical management including antihypertensive agents, lipid-lowering agents, and anti-platelet therapy. On multivariate analysis, remote prior TIA/stroke and lack of anti-platelet therapy remained significant. Among symptomatic patients presenting with stroke, lack of anti-platelet therapy was associated with an overall larger area of parenchymal involvement. No difference was observed with single versus dual anti-platelet therapy. Furthermore, symptomatic patients were more likely to have ulcerated plaques (30.9% vs 18%, p < .001), and symptomatic patients with ulcerated plaques more frequently had less than 50% compared to moderate/severe CAS. Nine patients who presented with symptoms had mild CAS and underwent intervention. CONCLUSIONS: Symptomatic CAS was associated with a history of remote prior symptoms and lack of anti-platelet therapy at time of presentation. Furthermore, symptomatic patients not on anti-platelet agents were more likely to have a greater area of parenchymal involvement when presenting with stroke and symptomatic patients with ulcerated plaques were more likely to have mild CAS, suggesting the role of plaque instability in symptomatic presentation. These findings underscore the importance of appropriate medical management and adherence in all patients with CAS and perhaps a role for more frequent surveillance in those with potentially unstable plaque morphology.

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.

Urgent endarterectomy for symptomatic carotid occlusion is associated with a high mortality.

OBJECTIVE: Interventions for carotid occlusions undertaken are undertaken and the outcomes are poorly defined. We sought to study patients undergoing urgent carotid revascularization for symptomatic occlusions. METHODS: The Society for Vascular Surgery Vascular Quality Initiative database was queried from 2003 to 2020 to identify patients with carotid occlusions undergoing carotid endarterectomy. Only symptomatic patients undergoing urgent interventions within 24 hours of presentation were included. Patients were identified based on computed tomography and magnetic resonance imaging. This cohort was compared with symptomatic patients undergoing urgent intervention for severe stenosis (≥80%). The primary end points were perioperative stroke, death, myocardial infarction (MI) and composite outcomes as defined by the Society for Vascular Surgery reporting guidelines. Patient characteristics were analyzed to determine predictors of perioperative mortality and neurological events. RESULTS: We identified 390 patients who underwent urgent CEA for symptomatic occlusions. The mean age was 67.4 ± 10.2 years (range, 39-90 years). The cohort was predominantly male (60%) with associated risk factors for cerebrovascular disease, including hypertension (87.4%), diabetes (34.4%), coronary artery disease (21.6%), and current smoking (38.7%). This population had high use of medications, including statins (78.6%), P2Y12 inhibitors (32.0%), aspirin (77.9%), and renin-angiotensin inhibitors (43.7%) preoperatively. When compared with patients undergoing urgent endarterectomy for severe stenosis (≥80%), those with symptomatic occlusion were well-matched with regard to risk factors, but the severe stenosis cohort seemed to be managed better medically and less likely to present with cortical stroke symptoms. Perioperative outcomes were significantly worse for the carotid occlusion cohort, primarily driven by higher perioperative mortality (2.8% vs 0.9%; P < .001). The composite end point of stroke/death/MI was also significantly worse in the occlusion cohort (7.7% vs 4.9%; P = .014). On multivariate analysis, carotid occlusion was associated with increased mortality (odds ratio, 3.028; 95% confidence interval, 1.362-6.730; P = .007) and composite outcome of stroke, death, or MI (odds ratio, 1.790; 95% confidence interval, 1.135-2.822; P = .012). CONCLUSIONS: Revascularization for symptomatic carotid occlusion constitutes approximately 2% of carotid interventions captured in the Vascular Quality Initiative, affirming the rarity of this undertaking. These patients have acceptable rates of perioperative neurological events, but are at an elevated risk of overall perioperative adverse events, primarily driven by higher mortality, compared with those with severe stenosis. Carotid occlusion seems to be the most significant risk factor for the composite end point of perioperative stroke, death, or MI. Although intervention for a symptomatic carotid occlusion may be performed with acceptable rate of perioperative complications, judicious patient selection is warranted in this high-risk cohort.

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.

Aortobifemoral reconstruction in open abdominal aortic aneurysm repair is associated with increased morbidity and mortality.

OBJECTIVE: Much attention has been given to the influence of anatomic and technical factors, such as maximum abdominal aortic aneurysm diameter and proximal clamp position, in open abdominal aortic aneurysm repair (OSR). However, no studies have rigorously examined the correlation between site of distal anastomosis and OSR outcomes despite conventional wisdom that more proximal sites of anastomosis are preferrable when technically feasible. This study aimed to test the association between sites of distal anastomosis and clinical outcomes for patients undergoing primary elective OSR. METHODS: Our study included 5683 patients undergoing primary elective OSR at 233 centers from 2014 to 2020. Using a variety of statistical methods to account for potential confounders, including multivariable logistic regression and Cox proportional hazards modeling, as well as subgroup analysis, we examined the association between site of distal anastomosis and clinical outcomes in elective OSR. Primary outcomes were major in-hospital complication rate, 30-day mortality, and long-term survival. RESULTS: Patients undergoing elective aortobifemoral reconstruction (n = 672) exhibited significantly increased rates of smoking, chronic obstructive pulmonary disease, and peripheral artery disease in comparison to patients undergoing elective OSR with distal anastomosis to the aorta (n = 2298), common iliac artery (n = 2163), or external iliac artery (n = 550). Patients undergoing aorto-aortic tube grafting were significantly less likely to exhibit iliac aneurysmal disease and significantly more likely to be undergoing elective OSR with a suprarenal or supraceliac proximal clamp position. Using multivariable logistic regression and Cox proportional hazards analysis to control for important confounders, such as age, smoking status, and medical history, we found that distal anastomosis to the common femoral artery was associated with increased odds of major in-hospital complications (adjusted odds ratio, 1.79; 95% confidence interval, 1.46-2.18; P < .001) and reduced long-term survival (adjusted hazard ratio, 1.44; 95% confidence interval, 1.09-1.89; P = .010). We observed no significant differences in 30-day mortality across sites of distal anastomosis in our study population. CONCLUSIONS: It is generally accepted that more proximal sites of distal anastomosis should be selected in OSR when technically feasible. Our findings support this hypothesis by demonstrating that distal anastomosis to the common femoral artery is associated with increased perioperative morbidity and reduced long-term survival. Careful diligence regarding optimization of preoperative health status, perioperative care, and long-term follow-up should be applied to mitigate major complications in this patient population.

The impact of aorto-uni-iliac graft configuration on outcomes of endovascular repair for ruptured abdominal aortic aneurysms.

INTRODUCTION: Endovascular aneurysm repair has improved outcomes for ruptured abdominal aortic aneurysms (rAAA) compared with open repair. We examined the impact of aorto-uni-iliac (AUI) vs standard bifurcated endograft configuration on outcomes in rAAA. METHODS: Patients 18 years or older in the Vascular Quality Initiative database who underwent endovascular aneurysm repair for rAAA from January 2011 to April 2020 were included. Patient characteristics were analyzed by graft configuration: AUI or standard bifurcated. Primary and secondary outcomes included 30-day mortality, postoperative major adverse events (myocardial infarction, stroke, heart failure, mesenteric ischemia, lower extremity embolization, dialysis requirement, reoperation, pneumonia, or reintubation), and 1-year mortality. A subset propensity-score matched cohort was also analyzed. RESULTS: We included 2717 patients: 151 had AUI and 2566 had standard bifurcated repair. There was no significant difference between the groups in terms of age, major medical comorbidities, anatomic aortic neck characteristics, or rates of conversion to open repair. Patients who underwent AUI were more commonly female (30% vs 22%, P = .011) and had a history of congestive heart failure (19% vs 12%, P = .013). Perioperatively, patients who underwent AUI had a significantly higher incidence of cardiac arrest (15% vs 7%, P < .001), greater intraoperative blood loss (1.3 L vs 0.6 L, P < .001), longer operative duration (218 minutes vs 138 minutes, P < .0001), higher incidence of major adverse events (46.3% vs 33.3%, P = .001), and prolonged intensive care unit (7 vs 4.7 days, P = .0006) and overall hospital length of stay (11.4 vs 8.1 days, P = .0003). Kaplan-Meier survival analyses demonstrated significant differences in 30-day (31.1% vs 20.2%, log-rank P = .001) and 1-year mortality (41.7% vs 27.7%, log-rank P = .001). The propensity-score matched cohort demonstrated similar results. CONCLUSIONS: The AUI configuration for rAAA appears to be implemented in a sicker cohort of patients and is associated with worse perioperative and 1-year outcomes compared with a bifurcated graft configuration, which was also seen on propensity-matched analysis. Standard bifurcated graft configuration may be the preferred approach in the management of rAAA unless AUI configuration is mandated by patient anatomy or other extenuating circumstances.