Early Injury Landscape in Vein Harvest by Single-Cell and Spatial Transcriptomics.

BACKGROUND: Vein graft failure following cardiovascular bypass surgery results in significant patient morbidity and cost to the healthcare system. Vein graft injury can occur during autogenous vein harvest and preparation, as well as after implantation into the arterial system, leading to the development of intimal hyperplasia, vein graft stenosis, and, ultimately, bypass graft failure. Although previous studies have identified maladaptive pathways that occur shortly after implantation, the specific signaling pathways that occur during vein graft preparation are not well defined and may result in a cumulative impact on vein graft failure. We, therefore, aimed to elucidate the response of the vein conduit wall during harvest and following implantation, probing the key maladaptive pathways driving graft failure with the overarching goal of identifying therapeutic targets for biologic intervention to minimize these natural responses to surgical vein graft injury. METHODS: Employing a novel approach to investigating vascular pathologies, we harnessed both single-nuclei RNA-sequencing and spatial transcriptomics analyses to profile the genomic effects of vein grafts after harvest and distension, then compared these findings to vein grafts obtained 24 hours after carotid-carotid vein bypass implantation in a canine model (n=4). RESULTS: Spatial transcriptomic analysis of canine cephalic vein after initial conduit harvest and distention revealed significant enrichment of pathways (P<0.05) involved in the activation of endothelial cells (ECs), fibroblasts, and vascular smooth muscle cells, namely pathways responsible for cellular proliferation and migration and platelet activation across the intimal and medial layers, cytokine signaling within the adventitial layer, and ECM (extracellular matrix) remodeling throughout the vein wall. Subsequent single-nuclei RNA-sequencing analysis supported these findings and further unveiled distinct EC and fibroblast subpopulations with significant upregulation (P<0.05) of markers related to endothelial injury response and cellular activation of ECs, fibroblasts, and vascular smooth muscle cells. Similarly, in vein grafts obtained 24 hours after arterial bypass, there was an increase in myeloid cell, protomyofibroblast, injury response EC, and mesenchymal-transitioning EC subpopulations with a concomitant decrease in homeostatic ECs and fibroblasts. Among these markers were genes previously implicated in vein graft injury, including VCAN, FBN1, and VEGFC, in addition to novel genes of interest, such as GLIS3 and EPHA3. These genes were further noted to be driving the expression of genes implicated in vascular remodeling and graft failure, such as IL-6, TGFBR1, SMAD4, and ADAMTS9. By integrating the spatial transcriptomics and single-nuclei RNA-sequencing data sets, we highlighted the spatial architecture of the vein graft following distension, wherein activated and mesenchymal-transitioning ECs, myeloid cells, and fibroblasts were notably enriched in the intima and media of distended veins. Finally, intercellular communication network analysis unveiled the critical roles of activated ECs, mesenchymal-transitioning ECs, protomyofibroblasts, and vascular smooth muscle cells in upregulating signaling pathways associated with cellular proliferation (MDK [midkine], PDGF [platelet-derived growth factor], VEGF [vascular endothelial growth factor]), transdifferentiation (Notch), migration (ephrin, semaphorin), ECM remodeling (collagen, laminin, fibronectin), and inflammation (thrombospondin), following distension. CONCLUSIONS: Vein conduit harvest and distension elicit a prompt genomic response facilitated by distinct cellular subpopulations heterogeneously distributed throughout the vein wall. This response was found to be further exacerbated following vein graft implantation, resulting in a cascade of maladaptive gene regulatory networks. Together, these results suggest that distension initiates the upregulation of pathological pathways that may ultimately contribute to bypass graft failure and presents potential early targets warranting investigation for targeted therapies. This work highlights the first applications of single-nuclei and spatial transcriptomic analyses to investigate venous pathologies, underscoring the utility of these methodologies and providing a foundation for future investigations.

Perivascular CLICK-gelatin delivery of thrombospondin-2 small interfering RNA decreases development of intimal hyperplasia after arterial injury.

Bypass graft failure occurs in 20%-50% of coronary and lower extremity bypasses within the first-year due to intimal hyperplasia (IH). TSP-2 is a key regulatory protein that has been implicated in the development of IH following vessel injury. In this study, we developed a biodegradable CLICK-chemistry gelatin-based hydrogel to achieve sustained perivascular delivery of TSP-2 siRNA to rat carotid arteries following endothelial denudation injury. At 21 days, perivascular application of TSP-2 siRNA embedded hydrogels significantly downregulated TSP-2 gene expression, cellular proliferation, as well as other associated mediators of IH including MMP-9 and VEGF-R2, ultimately resulting in a significant decrease in IH. Our data illustrates the ability of perivascular CLICK-gelatin delivery of TSP-2 siRNA to mitigate IH following arterial injury.

Association of stroke or death with severity of carotid lesion calcification in patients undergoing carotid artery stenting.

OBJECTIVE: Carotid artery stenting (CAS) for heavily calcified lesions is controversial due to concern for stent failure and increased perioperative stroke risk. However, the degree to which calcification affects outcomes is poorly understood, particularly in transcarotid artery revascularization (TCAR). With the precipitous increase in TCAR use and its expansion to standard surgical-risk patients, we aimed to determine the impact of lesion calcification on CAS outcomes to ensure its safe and appropriate use. METHODS: We identified patients in the Vascular Quality Initiative who underwent first-time transfemoral CAS (tfCAS) and TCAR between 2016 and 2021. Patients were stratified into groups based on degree of lesion calcification: no calcification, 1% to 50% calcification, 51% to 99% calcification, and 100% circumferential calcification or intraluminal protrusion. Outcomes included in-hospital and 1-year composite stroke/death, as well as individual stroke, death, and myocardial infarction outcomes. Logistic regression was used to evaluate associations between degree of calcification and these outcomes. RESULTS: Among 21,860 patients undergoing CAS, 28% patients had no calcification, 34% had 1% to 50% calcification, 35% had 51% to 99% calcification, and 3% had 100% circumferential calcification/protrusion. Patients with 51% to 99% and circumferential calcification/protrusion had higher odds of in-hospital stroke/death (odds ratio [OR], 1.3; 95% confidence interval [CI], 1.02-1.6; P = .034; OR, 1.9; 95% CI, 1.1-2.9; P = .004, respectively) compared with those with no calcification. Circumferential calcification was also associated with increased risk for in-hospital myocardial infarction (OR, 3.5; 95% CI, 1.5-8.0; P = .003). In tfCAS patients, only circumferential calcification/protrusion was associated with higher in-hospital stroke/death odds (OR, 2.0; 95% CI, 1.2-3.4; P = .013), whereas for TCAR patients, 51% to 99% calcification was associated with increased odds of in-hospital stroke/death (OR, 1.5; 95% CI, 1.1-2.2; P = .025). At 1 year, circumferential calcification/protrusion was associated with higher odds of ipsilateral stroke/death (12.4% vs 6.6%; hazard ratio, 1.64; P = .002). CONCLUSIONS: Among patients undergoing CAS, there is an increased risk of in-hospital stroke/death for lesions with >50% calcification or circumferential/protruding plaques. Increasing severity of carotid lesion calcification is a significant risk factor for stroke/death in patients undergoing CAS, regardless of approach.

Lower Extremity Bypass for Occlusive Disease: A Brief History.

BACKGROUND: This is a narrative review that aims to highlight key advancements that led to the current state of lower extremity bypass surgery. It focuses on key contributors during the last century who have driven the standardization of surgical treatment of peripheral arterial occlusive disease. METHODS: A narrative review was conducted utilizing available resources in the scientific and historical literature to track landmark achievements in the development of modern lower extremity bypass surgery for occlusive disease, focusing primarily on the last century of advancement. RESULTS: Several critical conceptual, technological, and technical landmarks were identified as critical components of modern lower extremity bypass surgery. This includes fundamental developments in the techniques of vascular anastomosis led by Carrel and others, a developing understanding of vascular occlusive disease as a localized and segmental process with broad implementation of the techniques of arteriography, and the development of safe thromboendarterectomy aided by the development and utilization of heparin for anticoagulation. These factors led to the first femoral-to-popliteal artery bypass by Jean Kunlin in 1948. From here, advances in vascular prosthetic material pioneered by Voorhees and others, alternative vascular conduits, increasing acceptance of tibial revascularization, and dispelling the myth of diabetic "small vessel" disease broadened revascularization options for patients with complex patterns of occlusive disease and those who have limited conduit availability. CONCLUSIONS: Modern lower extremity bypass surgery for occlusive disease arose steadily over a course of a century, driven by complex problem-solving in the pathophysiological understanding of atherosclerosis, technical developments in vascular anastomosis and arteriography, and evolution of conduit materials and pharmacologic therapy. Future advancements in bypass surgery are targeted at solving the complex problems of anastomotic intimal hyperplasia, expanding technology for alternative vascular conduits, ongoing optimization of risk factors, and scrutinizing of outcomes to make patient-centered, evidence-based decisions regarding revascularization strategy.

Advancements in Omics and Breakthrough Gene Therapies: A Glimpse into the Future of Peripheral Artery Disease.

Peripheral artery disease (PAD), a highly prevalent global disease, associates with significant morbidity and mortality in affected patients. Despite progress in endovascular and open revascularization techniques for advanced PAD, these interventions grapple with elevated rates of arterial restenosis and vein graft failure attributed to intimal hyperplasia (IH). Novel multiomics technologies, coupled with sophisticated analyses tools recently powered by advances in artificial intelligence, have enabled the study of atherosclerosis and IH with unprecedented single-cell and spatial precision. Numerous studies have pinpointed gene hubs regulating pivotal atherogenic and atheroprotective signaling pathways as potential therapeutic candidates. Leveraging advancements in viral and nonviral gene therapy (GT) platforms, gene editing technologies, and cutting-edge biomaterial reservoirs for delivery uniquely positions us to develop safe, efficient, and targeted GTs for PAD-related diseases. Gene therapies appear particularly fitting for ex vivo genetic engineering of IH-resistant vein grafts. This manuscript highlights currently available state-of-the-art multiomics approaches, explores promising GT-based candidates, and details GT delivery modalities employed by our laboratory and others to thwart mid-term vein graft failure caused by IH, as well as other PAD-related conditions. The potential clinical translation of these targeted GTs holds the promise to revolutionize PAD treatment, thereby enhancing patients' quality of life and life expectancy.

Bailout Distal Internal Carotid Artery Stenting after Carotid Endarterectomy: Indications, Technique, and Outcomes.

BACKGROUND: Distal internal carotid artery (ICA) stenting may be employed as a bailout maneuver when an inadequate end point or clamp injury is encountered at the time of carotid endarterectomy (CEA) in a surgically inaccessible region of the distal ICA. We sought to characterize the indications, technique, and outcomes for this infrequently encountered clinical scenario. METHODS: We performed a retrospective review of all patients who underwent distal ICA stenting at the time of CEA at our institution between September 2008 and July 2022. Procedural details and postoperative follow-up were reviewed for each patient. RESULTS: Six patients were identified during the study period. All were male with an age range of 63 to 82 years. Five underwent carotid revascularization for asymptomatic carotid artery stenosis, and one patient was treated for amaurosis fugax. Three patients were on dual antiplatelet therapy preoperatively, whereas 2 were on aspirin monotherapy, and one was on aspirin and low-dose rivaroxaban. Five patients underwent CEA with patch angioplasty, and one underwent eversion CEA. The indication for stenting was distal ICA dissection due to clamp or shunt injury in 2 patients and an inadequate distal ICA end point in 4 patients. In all cases, access for stenting was obtained under direct visualization within the common carotid artery, and a standard carotid stent was deployed with its proximal aspect landing within the endarterectomized site. Embolic protection was typically achieved via proximal common carotid artery and external carotid artery clamping for flow arrest with aspiration of debris before restoration of antegrade flow. There was 100% technical success. Postoperatively, 2 patients were found to have a cranial nerve injury, likely occurring due to the need for high ICA exposure. Median length of stay was 2 days (range 1-7 days) with no instances of perioperative stroke or myocardial infarction. All patients were discharged on dual antiplatelet therapy with no further occurrence of stroke, carotid restenosis, or reintervention through a median follow-up of 17 months. CONCLUSIONS: Distal ICA stenting is a useful adjunct in the setting of CEA complicated by inadequate end point or vessel dissection in a surgically inaccessible region of the ICA and can minimize the need for high-risk extensive distal dissection of the ICA in this situation.

A Multidisciplinary Protocolized Approach for Ruptured Abdominal Aortic Aneurysm Management: A Retrospective Before-After Study.

OBJECTIVES: To investigate whether implementation of a multidisciplinary protocol for ruptured abdominal aortic aneurysm (rAAA) management reduces rates of adverse complications. DESIGN: A retrospective before-after study. SETTING: A tertiary-care academic hospital. PARTICIPANTS: Adult patients who underwent open or endovascular rAAA repair; data were stratified into before-protocol implementation (group 1: 2015-2018) and after-protocol implementation (group 2: 2019-2022) groups. INTERVENTION: The protocol details the workflow for vascular surgery, anesthesia, emergency department, and operating room staff for a rAAA case; training was accomplished through yearly workshops. MEASUREMENTS AND MAIN RESULTS: The primary outcome was in-hospital mortality. Secondary outcomes included all-cause morbidity and other major complications. Differences in postoperative complication rates between groups were assessed using Pearson's χ2 test. Of the 77 patients included undergoing rAAA repair, 41 (53.2%) patients were in group 1, and 36 (46.8%) patients were in group 2. Patients in group 2 had a significantly shorter median time to incision (1.0 v 0.7 hours, p = 0.022) and total procedure time (180.0 v 160.5 minutes, p = 0.039) for both endovascular and open repair. After protocol implementation, patients undergoing endovascular repair exhibited significantly lower rates of mortality (46.2% v 20.0%, p = 0.048), all-cause morbidity (65.4% v 44.0%, p = 0.050), and renal complications (15.4% v 0.0%, p = 0.036); patients undergoing open repair for a rAAA exhibited significantly lower rates of mortality (53.3% v 27.3%, p = 0.018) and bowel ischemia (26.7% v 0.0%, p = 0.035). CONCLUSIONS: Implementation of a multidisciplinary protocol for the management of a rAAA may reduce rates of adverse complications and improve the quality of care.

Pedicled Flaps for High-Risk Open Vascular Procedures of the Lower Extremity: An Analysis of The National Surgical Quality Improvement Project Database.

BACKGROUND: Use of pedicled flaps in vascular procedures is associated with decreased infection and wound breakdown. We evaluated the risk profile and postoperative complications associated with lower extremity open vascular procedures with and without pedicled flaps. METHODS: The American College of Surgeons National Surgical Quality Improvement Program database (2010-2020) was queried for Current Procedural Terminology codes representing lower extremity open vascular procedures, including trunk and lower extremity pedicled flaps. Flap patients were compared with a randomized control group without flaps (1:3 cases to controls). Univariate and multivariate analyses were performed. RESULTS: We identified 132,934 adults who underwent lower extremity open vascular procedures. Concurrent pedicled flaps were rare (0.7%), and patients undergoing bypass procedures were more likely to receive a flap than nonbypass patients (69 vs. 64%, p < 0.0001). Flap patients had greater comorbidities. On univariate analysis, flap patients were more likely to experience wound (p = 0.0026), mild systemic (p < 0.0001), severe systemic (p = 0.0452), and all-cause complications (p < 0.0001). After adjusting for factors clinically suspected to be associated with increased risk (gender, body mass index, procedure type, American Society of Anesthesiologists classification, functional status, diabetes, smoking, and albumin < 3.5 mg/dL), wound (p = 0.096) and severe systemic complications (p = 0.0719) were no longer significantly associated with flap patients. CONCLUSION: Lower extremity vascular procedures are associated with a high risk of complications. Use of pedicled flaps remains uncommon and more often performed in patients with greater comorbid disease. However, after risk adjustment, use of a pedicled flap in high-risk patients may be associated with lower than expected wound and severe systemic complications.

Impact of neighborhood social disadvantage on carotid artery disease presentation, management, and discharge outcomes.

OBJECTIVE: Recent studies have highlighted that race and socioeconomic status serve as important determinants of disease presentation and perioperative outcomes in carotid artery disease. However, these investigations only focus on individual factors of social disadvantage, and fail to account for community factors that may drive disparities. Area Deprivation Index (ADI) is a validated measure of neighborhood adversity that offers a more comprehensive assessment of social disadvantage. We examined the impact of ADI ranking on carotid artery disease severity, management, and postoperative outcomes. METHODS: We identified patients who underwent carotid endarterectomy (CEA), transfemoral carotid artery stenting (tfCAS), and transcarotid artery revascularization (TCAR) in the Vascular Quality Initiative registry between 2016 and 2020. Patients were assigned ADI scores of 1 to 100 based on zip codes and grouped into quintiles, with higher quintiles reflecting increasing adversity. Outcomes assessed included disease presentation, intervention type, and discharge patterns. Logistic regression was used to evaluate independent associations between ADI quintiles and these outcomes. RESULTS: Among 91,904 patients undergoing carotid revascularization, 9811 (10.7%) were in the lowest ADI quintile (Q1), 18,905 (20.6%) in Q2, 25,442 (27.7%) in Q3, 26,099 (28.4%) in Q4, and 11,647 (12.7%) in Q5. With increasing ADI quintiles, patients were more likely to present with symptomatic disease (Q5, 52.1% vs Q1, 46.6%; P < .001), and stroke vs transient ischemic attack (Q5, 63.1% vs Q1, 53.5%; P < .001); they also more frequently underwent CAS vs CEA (Q5, 46.4% vs Q1, 33.9%; P < .001), and specifically tfCAS vs TCAR (Q5, 54.2% vs Q1, 33.9%; P < .001). In adjusted analyses, higher ADI quintiles remained as independent risk factors for presenting with symptomatic disease and stroke and undergoing CAS and tfCAS. Across ADI quintiles, patients were more likely to experience death (Q5, 0.8% vs Q1, 0.4%; P < .001), stroke/death (Q5, 2.1% vs Q1, 1.6%; P = .001), failure to discharge home (Q5, 11.5% vs Q1, 8.0%; P < .001) and length of stay >2 days (Q5, 33.3% vs Q1, 26.3%; P < .001) following revascularization. CONCLUSIONS: Among carotid revascularization patients, those with greater neighborhood social disadvantage had greater disease severity and more frequently underwent tfCAS. These patients also had higher rates of death and stroke/death, were less frequently discharged home, and had prolonged hospital stays. Greater efforts are needed to ensure that patients in higher ADI quintiles undergo better carotid surveillance and are treated appropriately for their carotid artery disease.

Impact of neighborhood social disadvantage on the presentation and management of peripheral artery disease.

OBJECTIVE: Studies examining the relationship between socioeconomic disparities and peripheral artery disease (PAD) often focus on individual social health determinants and fail to account for the complex interplay between factors that ultimately impact disease severity and outcomes. Area deprivation index (ADI), a validated measure of neighborhood adversity, provides a more comprehensive assessment of social disadvantage. Therefore, we examined the impact of ADI on PAD severity and its management. METHODS: We identified all patients who underwent infrainguinal revascularization (open or endovascular) or amputation for symptomatic PAD in the Vascular Quality Initiative registry between 2003 and 2020. An ADI score of 1 to 100 was assigned to each patient based on their residential zip code, with higher ADI scores corresponding with increasing adversity. Patients were categorized by ADI quintiles (Q1-Q5). The outcomes of interest included indication for procedure (claudication, rest pain, or tissue loss) and rates of revascularization (vs primary amputation). Multinomial logistic regression was used to evaluate for an independent association between ADI quintile and these outcomes. RESULTS: Among the 79,973 patients identified, 9604 (12%) were in the lowest ADI quintile (Q1), 14,961 (18.7%) in Q2, 19,800 (24.8%) in Q3, 21,735 (27.2%) in Q4, and 13,873 (17.4%) in Q5. There were significant trends toward lower rates of claudication (Q1: 39% vs Q5: 34%, P < .001), higher rates of rest pain (Q1: 12.4% vs Q5: 17.8%, P < .001) as the indication for intervention, and lower rates of revascularization (Q1: 80% vs Q5: 69%, P < .001) with increasing ADI quintiles. In adjusted analyses, there was a progressively higher likelihood of presenting with rest pain vs claudication, with patients in Q5 having the highest probability when compared with those in Q1 (relative risk: 2.0; 95% confidence interval: 1.8-2.2; P < .001). Patients in Q5, when compared with those in Q1, also had a higher likelihood of presenting with tissue loss vs claudication (relative risk: 1.4; 95% confidence interval: 1.3-1.6; P < .001). Compared with patients in Q1, patients in Q2-Q5 had a lower likelihood of undergoing any revascularization procedure. CONCLUSIONS: Among patients who underwent infrainguinal revascularization or amputation in the Vascular Quality Initiative, those with higher neighborhood adversity had more advanced disease at presentation and lower rates of revascularization. Further work is needed to better understand neighborhood factors that are contributing to these disparities in order to identify community-level targets for improvement.

Efficacy and safety of single versus dual antiplatelet therapy in carotid artery stenting.

OBJECTIVE: Current guidelines recommend dual antiplatelet (AP) therapy (DAPT) before carotid artery stenting (CAS); however, the true clinical effect of single AP therapy vs DAPT is unknown. We examined the efficacy and safety of preoperative single AP therapy vs DAPT in patients who had undergone transfemoral CAS (tfCAS) or transcarotid artery revascularization (TCAR). METHODS: We identified all patients who had undergone tfCAS or TCAR in the Vascular Quality Initiative database from 2016 to 2021. We stratified the patients by procedure and identified those who had received the following preoperative AP regimens: DAPT (acetylsalicylic acid [ASA] + P2Y12 inhibitor [P2Yi]), no AP therapy, ASA only, ASA + AP loading dose, P2Yi only, and P2Yi + AP loading dose. The AP loading dose was given within 4 hours of CAS. We generated propensity scores for each treatment regimen and assessed in-hospital outcomes using inverse probability weighted log binomial regression, with DAPT as the reference and adjusting for intraoperative protamine use. The primary efficacy outcome was a composite end point of stroke and death, and the primary safety outcome was access-related bleeding. RESULTS: Of the 18,570 tfCAS patients, 70% had received DAPT, 5.6% no AP therapy, 10% ASA only, 8.0% ASA + AP loading dose, 4.6% P2Yi only, and 2.9% P2Yi + AP loading dose. The corresponding unadjusted rates of stroke/death were 2.2%, 6.8%, 4.1%, 5.1%, 2.4%, and 2.3%. After adjustment, compared with DAPT, the incidence of stroke/death was higher with no AP therapy (relative risk [RR], 2.3; 95% confidence interval [CI], 1.7-3.2), ASA only (RR, 1.6; 95% CI, 1.2-2.1), and ASA + AP loading dose (RR, 2.0; 95% CI, 1.5-2.7) but was similar with P2Yi only (RR, 0.99; 95% CI, 0.58-1.7) and P2Yi + AP loading dose (RR, 1.1; 95% CI, 0.49-2.5). Of the 25,459 TCAR patients, 81% had received DAPT, 2.0% no AP therapy, 5.5% ASA only, 3.5% ASA + AP loading dose, 4.9% P2Yi only, and 2.4% P2Yi + AP loading dose. The corresponding unadjusted rates of stroke/death were 1.5%, 3.3%, 3.3%, 2.9%, 1.2%, and 1.1%. After adjustment, compared with DAPT, the incidence of stroke/death was higher with no AP therapy (RR, 2.0; 95% CI, 1.2-3.3) and ASA only (RR, 2.2; 95% CI, 1.5-3.1), with a trend toward a higher incidence with ASA + AP loading dose (RR, 1.6; 95% CI, 0.99-2.6), and was similar with P2Yi only (RR, 0.98; 95% CI, 0.54-1.8) and P2Yi + AP loading dose (RR, 0.66; 95% CI, 0.27-1.6). No differences were found in the incidence of access-related bleeding between the treatment groups after tfCAS or TCAR. CONCLUSIONS: Compared with DAPT, no AP therapy or ASA monotherapy was associated with higher rates of stroke/death after CAS and should be discouraged as unsafe practice. Meanwhile, P2Yi monotherapy was associated with similar rates of stroke/death. No differences were found in the incidence of bleeding complications, and adding an AP loading dose to ASA or P2Yi monotherapy within 4 hours of the procedure did not affect the outcomes. Overall, these findings support the current guidelines recommending DAPT before CAS but also suggest that P2Yi monotherapy might confer thromboembolic benefits similar to those with DAPT. However, an immediate preoperative AP loading dose might not provide additional thromboembolic benefits.

Distal embolic protection use during transfemoral carotid artery stenting is associated with improved in-hospital outcomes.

OBJECTIVE: Despite current guidelines recommending the use of distal embolic protection during transfemoral carotid artery stenting (tfCAS) to prevent periprocedural stroke, there remains significant variation in the routine use of distal filters. We sought to assess in-hospital outcomes in patients undergoing tfCAS with and without embolic protection using a distal filter. METHODS: We identified all patients undergoing tfCAS in the Vascular Quality Initiative from March 2005 to December 2021 and excluded those who received proximal embolic balloon protection. We created propensity score-matched cohorts of patients who underwent tfCAS with and without attempted placement of a distal filter. Subgroup analyses of patients with failed vs successful filter placement and failed vs no attempt at filter placement were performed. In-hospital outcomes were assessed using log binomial regression, adjusted for protamine use. Outcomes of interest were composite stroke/death, stroke, death, myocardial infarction (MI), transient ischemic attack (TIA), and hyperperfusion syndrome. RESULTS: Among 29,853 patients who underwent tfCAS, 28,213 (95%) had a filter attempted for distal embolic protection and 1640 (5%) did not. After matching, 6859 patients were identified. No attempted filter was associated with significantly higher risk of in-hospital stroke/death (6.4% vs 3.8%; adjusted relative risk [aRR], 1.72; 95% confidence interval [CI], 1.32-2.23; P < .001), stroke (3.7% vs 2.5%; aRR, 1.49; 95% CI, 1.06-2.08; P = .022), and mortality (3.5% vs 1.7%; aRR, 2.07; 95% CI, 1.42-3.020; P < .001). In a secondary analysis of patients who had failed attempt at filter placement vs successful filter placement, failed filter placement was associated with worse outcomes (stroke/death: 5.8% vs 2.7%; aRR, 2.10; 95% CI, 1.38-3.21; P = .001 and stroke: 5.3% vs 1.8%; aRR, 2.87; 95% CI, 1.78-4.61; P < .001). However, there were no differences in outcomes in patients with failed vs no attempted filter placement (stroke/death: 5.4% vs 6.2%; aRR, 0.99; 95% CI, 0.61-1.63; P = .99; stroke: 4.7% vs 3.7%; aRR, 1.40; 95% CI, 0.79-2.48; P = .20; death: 0.9% vs 3.4%; aRR, 0.35; 95% CI, 0.12-1.01; P = .052). CONCLUSIONS: tfCAS performed without attempted distal embolic protection was associated with a significantly higher risk of in-hospital stroke and death. Patients undergoing tfCAS after failed attempt at filter placement have equivalent stroke/death to patients in whom no filter was attempted, but more than a two-fold higher risk of stroke/death compared with those with successfully placed filters. These findings support current Society for Vascular Surgery guidelines recommending routine use of distal embolic protection during tfCAS. If a filter cannot be placed safely, an alternative approach to carotid revascularization should be considered.

Discrepancies in clavicle-to-carotid bifurcation length measurements for transcarotid artery revascularization using different imaging modalities.

OBJECTIVE: Transcarotid artery revascularization (TCAR) has emerged as an effective method for carotid artery stenting. However, anatomic eligibility for TCAR is most often limited by an inadequate clavicle-to-carotid bifurcation length of <5 cm. Preoperative clavicle-to-carotid bifurcation distances may be underestimated when using conventional straight-line measurements on computed tomographic angiography (CTA) imaging. We therefore compared clavicle-to-carotid bifurcation lengths as measured by straight-line CTA, center-line CTA, and intraoperative duplex ultrasound (US), to assess potential differences. METHODS: We conducted a single-center, retrospective review of consecutive TCAR procedures performed between 2016 and 2019 for atherosclerotic carotid disease. For each patient, we compared clavicle-to-carotid bifurcation lengths measured by straight-line CTA, center-line CTA using TeraRecon image reconstruction, and intraoperative duplex US with neck extension and rotation. We further assessed patient and imaging characteristics in individuals with a ≥0.5 cm difference among the measurement methods. In particular, common carotid artery (CCA) tortuosity, defined as the inability to visualize the entire CCA from clavicle to carotid bifurcation on both a single coronal and sagittal imaging cut, was examined as a contributing factor for these discrepancies. RESULTS: Of the 70 TCAR procedures identified, 46 had all three imaging modalities available for review. The median clavicle-to-carotid bifurcation length was found to be 6.4 cm (interquartile range [IQR], 5.4-6.7 cm) on straight-line CTA, 7.0 cm (IQR, 6.0-7.5 cm) on intraoperative duplex US, and 7.2 cm (IQR, 6.5-7.5 cm) on center-line CTA (P < .001). Patients with a ≥0.5 cm difference between their straight-line CTA and either their intraoperative duplex US or center-line CTA measurements were more likely to have tortuous CCAs (60.0% vs 19.1%; P = .01; 51.4% vs 0.0%; P = .01). There were no notable differences in age, gender, prior neck/cervical spine surgery, or neck immobility among these individuals. In patients with tortuous CCAs, duplex US and center-line CTA measurements added 1.0 cm (IQR, 0.6-1.5 cm) and 1.1 cm (IQR, 0.9-1.6 cm) more in length than straight-line CTA measurements, respectively. There was a strong linear correlation between the additional lengths provided by duplex US measurements and those provided by center-line CTA measurements for each individual within the tortuous CCA group (r = 0.83). CONCLUSIONS: The use of straight-line CTA during preoperative planning can underestimate the clavicle-to-carotid bifurcation lengths in patients undergoing carotid revascularization, particularly in those with tortuous CCAs. Both duplex US performed with extended-neck surgical positioning and center-line CTA provide similar and longer carotid length measurements, and should be utilized in patients with tortuous carotid vessels to better determine TCAR anatomic eligibility.

Efficacy and safety of perioperative dual antiplatelet therapy with ticagrelor versus clopidogrel in carotid artery stenting.

BACKGROUND: Clopidogrel resistance is associated with increased periprocedural neurologic events after carotid artery stenting (CAS). Ticagrelor offers an improved resistance profile; however, its bleeding risk has not been assessed with CAS. Therefore, we examined the efficacy and safety of perioperative dual antiplatelet therapy with aspirin/ticagrelor vs aspirin/clopidogrel in patients undergoing transfemoral carotid artery stenting (tfCAS) or transcarotid artery revascularization (TCAR). METHODS: We identified all patients who underwent tfCAS or TCAR in the Vascular Quality Initiative registry from January 2016 to March 2021. We stratified patients by procedure and assessed outcomes using 1:3 propensity score-matched cohorts of patients who received perioperative aspirin/ticagrelor vs aspirin/clopidogrel. The primary efficacy outcome was a composite endpoint of in-hospital stroke/death, and the primary safety outcome was access-related bleeding. As a secondary analysis, we assessed these outcomes after stratifying each cohort by intraoperative protamine use. RESULTS: Among 17,731 tfCAS patients, 593 (3.3%) received aspirin/ticagrelor and 11,404 (64%) received aspirin/clopidogrel. For the 2065 matched patients, no significant differences were found in the composite endpoint of stroke/death (aspirin/ticagrelor, 4.1%; vs aspirin/clopidogrel, 2.6%; relative risk [RR],1.5; 95% confidence interval [CI], 0.88-2.7) or in the individual endpoints of stroke (2.9% vs 1.8%; RR, 1.6; 95% CI, 0.87-3.0) or death (1.7% vs 1.1%; RR, 1.6; 95% CI, 0.71-3.5). However, aspirin/ticagrelor was associated with a higher risk of bleeding (5.8% vs 2.8%; RR, 2.0; 95% CI, 1.2-3.2). In a subgroup analysis of 297 tfCAS patients (14%) who received intraoperative protamine, no differences remained in stroke/death (1.5% vs 3.9%; RR, 0.38; 95% CI, 0.05-3.0), and there was no longer a difference in bleeding (3.0% vs 2.6%; RR, 1.1; 95% CI, 0.24-5.5). Among 17,946 TCAR patients, 453 (2.5%) received aspirin/ticagrelor and 13,696 (76%) received aspirin/clopidogrel. For the 1618 matched patients, no differences were found in stroke/death (0.7% vs 1.4%; RR, 0.53; 95% CI, 0.16-1.8), stroke (0.2% vs 1.2%; RR, 0.20; 95% CI, 0.03-1.5), death (0.5% vs 0.2%; RR, 3.0; 95% CI, 0.42-21), or bleeding (1.2% vs 1.6%; RR, 0.75; 95% CI, 0.28-2.0). For the 1429 TCAR patients (88%) who received protamine, no differences were found in stroke/death (0.8% vs 1.2%; RR, 0.68; 95% CI, 0.20-2.4) or bleeding (0.6% vs 1.4%; RR, 0.39; 95% CI, 0.09-1.7). CONCLUSIONS: Compared with aspirin/clopidogrel, aspirin/ticagrelor was associated with a potentially lower risk of stroke/death and bleeding complications after CAS in cases in which protamine was used but a higher risk of these outcomes in the absence of protamine. Given our limited sample size, our analysis should be repeated when more patients are available for study. However, our findings suggest that aspirin/ticagrelor could be a reasonable alternative to aspirin/clopidogrel for both tfCAS and TCAR when protamine is used.

In-situ bypass is associated with superior infection-free survival compared with extra-anatomic bypass for the management of secondary aortic graft infections without enteric involvement.

OBJECTIVE: The optimal revascularization modality following complete resection of aortic graft infection (AGI) without enteric involvement remains unclear. The purpose of this investigation is to determine the revascularization approach associated with the lowest morbidity and mortality using real-world data in patients undergoing complete excision of AGI. METHODS: A retrospective, multi-institutional study of AGI from 2002 to 2014 was performed using a standardized database. Baseline demographics, comorbidities, and perioperative variables were recorded. The primary outcome was infection-free survival. Descriptive statistics, Kaplan-Meier survival analysis, and univariate and multivariable analyses were performed. RESULTS: A total of 241 patients at 34 institutions from seven countries presented with AGI during the study period (median age, 68 years; 75% male). The initial aortic procedures that resulted in AGI were 172 surgical grafts (71%), 66 endografts (27%), and three unknown (2%). Of the patients, 172 (71%) underwent complete excision of infected aortic graft material followed by in situ (in-line) bypass (ISB), including antibiotic-treated prosthetic graft (35%), autogenous femoral vein (neo-aortoiliac surgery) (24%), and cryopreserved allograft (41%). Sixty-nine patients (29%) underwent extra-anatomic bypass (EAB). Overall median Kaplan-Meier estimated survival was 5.8 years. Perioperative mortality was 16%. When stratified by ISB vs EAB, there was a significant difference in Kaplan-Meier estimated infection-free survival (2910 days; interquartile range, 391-3771 days vs 180 days; interquartile range, 27-3750 days; P < .001). There were otherwise no significant differences in presentation, comorbidities, or perioperative variables. Multivariable Cox regression showed lower infection-free survival among patients with EAB (hazard ratio [HR], 2.4; 95% confidence interval [CI], 1.6-3.6; P < .001), polymicrobial infection (HR, 2.2; 95% CI, 1.4-3.5; P = .001), methicillin-resistant Staphylococcus aureus infection (HR, 1.7; 95% CI, 1.1-2.7; P = .02), as well as the protective effect of omental/muscle flap coverage (HR, 0.59; 95% CI, 0.37-0.92; P = .02). CONCLUSIONS: After complete resection of AGI, perioperative mortality is 16% and median overall survival is 5.8 years. EAB is associated with nearly a two and one-half-fold higher reinfection/mortality compared with ISB. Omental and/or muscle flap coverage of the repair appear protective.

Protamine use in transfemoral carotid artery stenting is not associated with an increased risk of thromboembolic events.

BACKGROUND: Protamine use in carotid endarterectomy has been shown to be associated with fewer perioperative bleeding complications without higher rates of thromboembolic events. However, the effect of protamine use on complications after transfemoral carotid artery stenting (CAS) is unclear, and concerns remain about thromboembolic events. METHODS: A retrospective review was performed for patients undergoing transfemoral CAS in the Vascular Quality Initiative from March 2005 to December 2018. We assessed in-hospital outcomes using propensity score-matched cohorts of patients who did and did not receive protamine. The primary outcome was in-hospital stroke or death. Secondary outcomes included bleeding complications, stroke, death, transient ischemic attack, myocardial infarction, and congestive heart failure exacerbation. Bleeding complications were categorized as bleeding resulting in intervention or blood transfusions. RESULTS: Of the 17,429 patients undergoing transfemoral CAS, 2697 (15%) patients received protamine. We created 2300 propensity score-matched pairs of patients who did and did not receive protamine. There were no statistically significant differences in stroke or death between the two cohorts (protamine, 2.5%; no protamine, 2.9%; relative risk [RR], 0.85; 95% confidence interval [CI], 0.60-1.21; P = .37). Protamine use was not associated with statistically significant differences in perioperative bleeding complications resulting in interventional treatment (0.9% vs 0.5%; RR, 2.10; 95% CI, 0.99-4.46; P = .05) or blood transfusion (1.2% vs 1.2%; RR, 0.92; 95% CI, 0.53-1.61; P = .78). There were also no statistically significant differences for the individual outcomes of stroke (1.8% vs 2.3%; RR, 0.78; 95% CI, 0.52-1.16; P = .22), death (0.9% vs 0.8%; RR, 1.17; 95% CI, 0.62-2.19; P = .63), transient ischemic attack (1.4% vs 1.3%; RR, 1.10; 95% CI, 0.67-1.82; P = .70), myocardial infarction (0.5% vs 0.4%; RR, 1.20; 95% CI, 0.52-2.78; P = .67), or heart failure exacerbation (1.0% vs 0.9%; RR, 1.05; 95% CI, 0.58-1.90; P = .88). Protamine use in patients presenting with symptomatic carotid stenosis was associated with lower risk of stroke or death (3.0% vs 4.3%; RR, 0.69; 95% CI, 0.47-0.998; P = .048), whereas there were no statistically significant differences in stroke or death with protamine use in asymptomatic patients (1.6% vs 1.0%; RR, 1.63; 95% CI, 0.67-3.92; P = .28). CONCLUSIONS: Heparin reversal with protamine after transfemoral CAS is not associated with an increased risk of thromboembolic events, and its use in symptomatic carotid disease is associated with a lower risk of stroke or death.

Outcomes after transfemoral carotid artery stenting stratified by preprocedural symptom status.

OBJECTIVE: The available data on outcomes after transfemoral carotid artery stenting (TFCAS) originate from the early experience with TFCAS. Although most previous studies stratified outcomes according to a symptomatic or asymptomatic presentation, they often did not specify the degree of presenting neurologic injury. We previously reported that the outcomes after carotid endarterectomy differed according to neurologic injury severity, the contemporary perioperative outcomes of TFCAS stratified by the specific presenting symptom status are unknown. METHODS: Patients with data in the Vascular Quality Initiative database who had undergone TFCAS from 2016 to 2020 were included. We stratified patients according to their preprocedural symptom status as asymptomatic, formerly symptomatic (last symptoms >180 days before the procedure), or recently symptomatic (symptoms <180 days before the procedure). The symptoms included stroke, hemispheric transient ischemic attack (TIA), and ocular TIA. We compared the occurrence of in-hospital stroke or death (stroke/death) among the asymptomatic, formerly symptomatic, and specific subtypes of recently symptomatic patients. Multivariable logistic regression models were constructed to adjust for the baseline differences among the groups. RESULTS: Of the 9807 included patients, 2650 (27%) had had recent stroke, 842 (9%), recent hemispheric TIA, and 360 (4%), recent ocular TIA. In addition, 795 patients (8%) were formerly symptomatic and 5160 (53%) were asymptomatic. The patients with recent stroke had a perioperative stroke/death rate of 5.5%, higher than that of patients with recent hemispheric TIA (2.4%; P < .001) or recent ocular TIA (2.8%; P = .03) and asymptomatic patients (1.4%; P < .001). The stroke/death rate was greater for patients with recent ocular TIA than for asymptomatic patients (2.8% vs 1.4%; P = .04). Formerly symptomatic patients had higher stroke/death rates compared with asymptomatic patients (3.5% vs 1.4%; P < .001). On multivariable-adjusted analysis, recent stroke was associated with higher stroke/death compared with recent hemispheric TIA (odds ratio [OR], 2.6; 95% confidence interval [CI], 1.6-4.3; P < .001) and asymptomatic status (OR, 4.1; 95% CI, 3.0-5.6; P < .001) and demonstrated a trend toward higher stroke/death compared with recent ocular TIA (OR, 2.0; 95% CI, 1.0-3.9; P = .06). Furthermore, asymptomatic status was associated with lower stroke/death compared with formerly symptomatic status (OR, 0.4; 95% CI, 0.2-0.6; P < .001). CONCLUSIONS: For patients undergoing TFCAS, recent stroke was associated with greater odds of in-hospital stroke/death after TFCAS compared with recent hemispheric TIA. Also, formerly symptomatic status was associated with greater odds of stroke/death compared with asymptomatic status. These findings support further symptom stratification by the degree of the presenting neurologic injury in the preoperative risk assessment.

Validation of the Global Limb Anatomic Staging System in first-time lower extremity revascularization.

OBJECTIVE: The Global Limb Anatomic Staging System (GLASS) was developed as a new anatomic classification scheme to grade the severity of chronic limb threatening ischemia. We evaluated the ability of this anatomic grading system to determine major adverse limb events after lower extremity revascularization. METHODS: We performed a single-institutional retrospective review of 1060 consecutive patients who had undergone 1180 first-time open or endovascular revascularization procedures for chronic limb threatening ischemia from 2005 to 2014. Using the review of angiographic images, the limbs were classified as GLASS stage 1, 2, or 3. The primary composite outcome was reintervention, major amputation (below- or above-the-knee amputation), and/or restenosis (>3.5× step-up by duplex criteria) events (RAS). The secondary outcomes included all-cause mortality, failure to cross the lesion by endovascular methods, and a comparison between bypass vs endovascular intervention. Kaplan-Meier estimates were used to determine the event rates at 1 and 5 years, and Cox regression analysis was used to adjust for baseline differences among the GLASS stages. RESULTS: Of all patients undergoing first-time revascularization, imaging studies were available for 1180 procedures (91%) for GLASS grading. Of these procedures, 552 were open bypass (47%) and 628 were endovascular intervention (53%). Compared with GLASS stage 1 disease (n = 267, 23%), stage 2 (n = 367; 31%) and stage 3 (n = 546; 42%) disease were associated with a greater risk of RAS at 1 year (stage 1, 33% vs stage 2, 48% vs stage 3, 53%) and 5 years (stage 1, 45% [reference]; stage 2, 65%; hazard ratio [HR], 1.7; 95% confidence interval [CI], 1.3-2.2; P < .001; stage 3, 69%; HR, 2.3; 95% CI, 1.7-2.9; P < .001). These differences were mainly driven by reintervention and restenosis rather than by major amputation. The 5-year mortality was similar for stage 2 and 3 compared with stage 1 disease (stage 1, 40% [reference]; stage 2, 45%; HR, 1.1; 95% CI, 0.8-1.4; P = .69; stage 3, 49%; HR, 1.2; 95% CI, 1.0-1.6; P = .11). For all attempted endovascular interventions, failure to cross a target lesion increased with advancing GLASS stage (stage 1, 4.5% vs stage 2, 6.3% vs stage 3, 13.3%; P < .01). Compared with open bypass (n = 552; 46.8%), endovascular intervention (n = 628; 53.3%) was associated with a higher rate of 5-year RAS for GLASS stage 1 (49% vs 34%; HR, 1.9; 95% CI, [1.1-3.5; P = .03), stage 2 (69% vs 52%; HR, 1.7; 95% CI, 1.2-2.5; P < .01), and stage 3 (83% vs 61%; HR, 1.5; 95% CI, 1.2-2.0; P < .01) disease. CONCLUSIONS: For patients undergoing first-time lower extremity revascularization, the GLASS can be used to predict for reintervention and restenosis. Bypass resulted in better long-term outcomes compared with endovascular intervention for all GLASS stages.

Vascular Quality Initiative risk score for 30-day stroke or death following transcarotid artery revascularization.

OBJECTIVE: Transcarotid artery revascularization (TCAR) using a flow-reversal neuroprotection system has gained popularity for the endovascular treatment of carotid artery atherosclerotic disease owing to its lower risk of stroke or death compared with transfemoral carotid artery stenting. However, specific risk factors associated with stroke or death complications after TCAR have yet to be defined. METHODS: All patients undergoing TCAR for the treatment of asymptomatic or symptomatic atherosclerotic carotid disease were identified between September 2016 and September 2019 in the Vascular Quality Initiative TCAR Surveillance Project. Our primary outcome was 30-day stroke or death. We created a risk model for 30-day stroke or death using multivariable fractional polynomials and internally validated the model using bootstrapping. RESULTS: During the study period 7633 patients underwent TCAR, of which 4089 (53.6%) were treated for symptomatic and 3544 (46.4%) for asymptomatic disease. The average age of patients undergoing TCAR was 73.3 ± 9.1 years and 63.7% were male. Stroke or death events within 30 days of the index operation occurred in 153 patients (2.0%). Factors independently associated with a higher odds of 30-day stroke or death included the severity of presenting stroke symptoms (cortical transient ischemic attack, odds ratio [OR], 2.17 [95% confidence interval (CI), 1.21-3.90; P = .009]; stroke, OR, 3.30; 95% CI, 2.25-4.85; P < .001), advancing age (OR, 1.03 per year; 95% CI, 1.01-1.06; P = .003), and history of unstable angina or myocardial infarction within the past 6 months (OR, 2.20; 95% CI, 1.29-3.77; P = .004), moderate or severe congestive heart failure (OR, 2.44; 95% CI, 1.31-4.55; P = .005), chronic obstructive pulmonary disease (on medications, OR, 1.61 [95% CI, 1.06-2.43; P = .024]; on home oxygen, OR, 2.52 [95% CI, 1.44-4.41; P = .001]), and prior ipsilateral carotid endarterectomy (OR, 1.56; 95% CI, 1.09-2.25; P = .016), whereas preoperative P2Y12 use was associated with a lower odds of 30-day stroke or death (OR, 0.57; 95% CI, 0.39-0.85; P = .005). A 30-point risk prediction model created based on these criteria produced a C statistic of 0.72 and Hosmer-Lemeshow goodness of fit of 0.97. Internal validation demonstrated good discrimination with a bias corrected area under the receiver operating characteristic curve of 0.70 with a calibration slope of 1.00. CONCLUSIONS: This Vascular Quality Initiative TCAR risk score calculator can be used to estimate the risk of stroke or death within 30 days of the procedure. Because TCAR is commonly used to treat patients with high surgical risk for carotid endarterectomy, this risk score will help to guide treatment decisions in patients being considered for TCAR.

Epidemiology of endovascular and open repair for abdominal aortic aneurysms in the United States from 2004 to 2015 and implications for screening.

BACKGROUND: Contemporary national trends in the repair of ruptured abdominal aortic aneurysms (AAAs) and intact AAAs are relatively unknown. Furthermore, screening is only covered by insurance for patients aged 65 to 75 years with a family history of AAAs and for men with a positive smoking history. It is unclear what proportion of patients who present with a ruptured AAA would have been candidates for screening. METHODS: Using the National Inpatient Sample from 2004 to 2015, we identified ruptured and intact AAA admissions and repairs using the International Classification of Diseases codes. We generated the screening-eligible cohort using previously identified proportions of male smokers (87%) and all patients with a family history of AAAs (10%) and applied these proportions to patients aged 65 to 75 years. We accounted for those who could have had a previous AAA diagnosis (17%), either from screening or an incidental detection in patients aged >75 years who had presented with AAA rupture. The primary outcomes were treatment and in-hospital mortality between patients meeting the criteria for screening vs those who did not. RESULTS: We evaluated 65,125 admissions for ruptured AAAs and 461,191 repairs for intact AAAs. Overall, an estimated 45,037 admitted patients (68%) and 25,777 patients who had undergone repair for ruptured AAAs (59%) did not meet the criteria for screening. Of the patients who did not qualify, 27,653 (63%) were aged >75 years, 10,603 (24%) were aged <65 years, and 16,103 (36%) were women. Endovascular AAA repair (EVAR) increased for ruptured AAAs from 10% in 2004 to 55% in 2015 (P < .001), with operative mortality of 35%. EVAR increased for intact AAAs from 45% in 2004 to 83% in 2015 (P < .001), with operative mortality of 2.0%. CONCLUSIONS: Most patients who had undergone repair for ruptured AAAs did not qualify for screening. EVAR was the primary treatment of both ruptured and intact AAAs with relatively low in-hospital mortality. Therefore, expansion of the screening criteria to include selected women and a wider age range should be considered.