Carotid Stenting Research Articles

315 A Propensity Score-matched Comparative Study of Balloon Guide Catheters Versus Conventional Guide Catheters for Mechanical Thrombectomy With Stenting in Tandem Strokes: Comparison of 1st-pass Effect, Symptomatic ICH, and 90-day Functional Outcomes

INTRODUCTION: Extensive clot burden in tandem strokes accounts for poor mechanical thrombectomy (MT) outcomes. Several studies have shown benefit of balloon guide catheters (BGC) in MT and carotid artery stenting. METHODS: Tandem stroke patients identified from our endovascular database were dichotomized into groups treated with BGCs versus conventional guide catheters. One-to-one PSM adjustment for baseline demographics and treatment selection bias using nearest-neighbor matching was performed. Patient demographics, presentation characteristics, and procedural details were recorded. Outcomes assessed were final modified thrombolysis in cerebral infarction (mTICI) grade, periprocedural symptomatic intracranial hemorrhage (sICH) rate, in-hospital mortality, and 90-day modified Rankin Scale (mRS) score. Mann-Whitney U-test and multivariate logistic regression were performed to compare procedural parameters and clinical outcomes. RESULTS: Concurrent carotid revascularization (stenting with/without angioplasty) and MT was performed in 125 cases (BGC: 85; no BGC: 40). After PSM (40 patients/group), BGC group had a significantly shorter procedure duration (77.9 vs. 61.5 min; odds ratio [OR] = 0.996; p = 0.006), lower discharge National Institutes of Health Stroke Scale score (8.0 vs. 11.0; OR = 0.987; p = 0.042), and higher odds of 90-day mRS 0-2 score (52.3% vs. 27.5%; OR = 0.34; p = 0.040). On multivariate regression, BGC group had a significantly higher first-pass effect rate (mTICI: 2B-3) (OR = 1.115, 95% confidence interval [CI] = 1.015-1.432; p = 0.013) and lower periprocedural sICH rate (OR = 0.615; 95% CI = 0.406-0.932; p = 0.025). No difference in in-hospital mortality was observed (OR = 1.591; 95% CI = 0.976-2.593; p = 0.067). CONCLUSIONS: BGCs used for concurrent MT–carotid revascularization with flow arrest were safe and resulted in superior clinical and angiographic outcomes in tandem stroke patients.

708 Trends in Carotid Stenosis Literature Between 2012-2022: Applications of Endarterectomy and Translational Research

INTRODUCTION: Carotid stenosis causes 10-20% of cases with ischemic stroke. Research in this clinical domain continues to progress in improving possible treatment modalities, imaging modalities, mechanistic understandings, and risk factors. METHODS: The WebOfScience database was investigated for 6,639 publication items between 2012-2022 pertaining to neurosurgical management of carotid stenosis. Networks were constructed analyzing keywords, key terms, and countries of publication. Subsequently, items within each network were organized into clusters and average publication date was measured for each term. Relevant items were tracked over time to compare their representation and utility in literature. Additionally, relevant key terms and connections were isolated from the network. RESULTS: For each network, the top 1,000 terms were selected for analysis. Terms were arranged into six major clusters (treatments, imaging, risk factors, prognostic markers, plaque characteristics, and basic science research). The most recent terms were observed in the treatment cluster (average publication year 2021.24) and basic science cluster (average publication year 2018.4). While terms within basic science have remained consistent over time, analysis of treatments elucidated that “carotid endarterectomy” surpassed “carotid artery stenting” in popularity after 2019. Additionally, the term “mouse” in the basic science cluster was connected to all clusters with a link strength of 18,084 (average 427.6). CONCLUSIONS: Modern research in carotid stenosis is characterized by two developments: advancements in basic science and increasing publication focus on carotid endarterectomy. Despite recent advancements in endovascular treatment of carotid stenosis, open treatment continues to remain a significant focus of study. As they continue to expand into modern scientific enterprise, developing nations will continue to impact the future of carotid stenosis research.

107 Conventional Catheter-based Angiography Versus Non-invasive Imaging in the Evaluation of Symptomatic Carotid Disease

INTRODUCTION: The indication for invasive treatment of symptomatic carotid disease with CEA or carotid stenting was established based on catheter digitally subtracted imaging (DSA) however operative referral for symptomatic carotid disease is still largely based on non-invasive imaging such as CTA or ultrasound. METHODS: Retrospective analysis all consecutive patients who were referred for evaluation and treatment of symptomatic carotid disease after non-invasive imaging with CTA or ultrasound showed ipsilateral carotid stenosis of >50% or occlusion. Patients were included if they had ipsilateral cerebral or ocular ischemia within two weeks of index event. RESULTS: A total of 280 patients with stenosis >50 and <100% were included. Of those, 53 (19%) were found to have stenosis <50% leading to treatment with best medical therapy instead of intervention. Out of 50 patients with total occlusion, 16 (32%) were found to have a string sign and were treated with stenting. Percent stenosis of 80 or more on non-invasive imaging was more likely to correlate with stenosis of 50% or more on DSA. CONCLUSIONS: In a cohort of two large North American institutions, 19% of patients referred for revascularization of symptomatic carotid disease based on non-invasive imaging were found to have non-significant carotid stenosis and were treated with best medical therapy and 32% of those with suspected occlusion were successfully revascularized. Our findings highlight the importance of catheter cased angiography in the evaluation of carotid disease.

332 Descriptive Analysis of State and Federal Malpractice Litigation in the United States Related to Neuroendovascular Procedures

INTRODUCTION: Medical malpractice interests the medical community at large. While previous neurosurgical review articles have analyzed malpractice in the context of spinal surgery, few have reviewed malpractice data surrounding neurovascular procedures as a whole. METHODS: In this retrospective review Google Scholar Case Law, Casetext and Westlaw legal databases were searched for verdict and settlement reports pertaining to neurovascular procedures from 1984 to 2023. Data were collected regarding type of procedure, patient age and gender, defendant specialty, outcome, award, and alleged cause of malpractice. Search terms included “arteriovenous malformation,” “brain aneurysm,” “aneurysm coiling,” “subarachnoid hemorrhage,” “large vessel occlusion,” “mechanical thrombectomy,” “cerebral angiography,” “carotid angioplasty and stenting,” and “carotid stenosis.” Initial search produced 212 cases, after which exclusion criteria were applied to eliminate duplicates and cases unrelated to neurovascular surgery/diagnoses or malpractice, yielding 27 cases total. RESULTS: The verdict favored the defendant physician(s) individually or represented by a healthcare entity in 8 of the 27 cases selected for analysis. Of 19 cases with verdicts in favor of the plaintiff, settlement values ranged from $30,000 to $15.65 million. In settlement cases, the most commonly involved procedures included AVM embolization followed by aneurysm coiling. Amongst cases where interventionist was the defendant, the most common specialty was neurointerventional radiology, followed by neurosurgery. Failure to diagnose was the most cited alleged malpractice cause (51.8%) amongst all cases, regardless of verdict. CONCLUSIONS: Neurovascular emergencies are often addressed by a team of medical specialists including endovascular neurosurgeons, interventional neuroradiologists, and interventional neurologists. In this review, malpractice claims related to neurovascular emergencies most likely to result in plaintiff award were related to failure to diagnose, and interventional neuroradiologists appear to be at greater risk for alleged malpractice.

Quantitative assessment of retinochoroidal microvasculature in patients with carotid artery stenosis using OCT angiography

PurposeTo investigate the alterations in retinochoroidal parameters measured by optical coherence tomography (OCT) and OCT angiography (OCTA) in patients with carotid artery stenosis (CAS) and assess their associations with digital subtraction angiography (DSA) data. MethodThis study enrolled patients diagnosed with CAS and age-matched healthy controls. Both groups underwent OCT and OCTA examinations. DSA and assessment of carotid artery stenosis were performed only in the CAS group. The study evaluated various retinochoroidal parameters from OCT and OCTA, including linear vessel density (LVD), foveal avascular zone (FAZ), choroidal thickness (ChT), and retinal nerve fiber layer (RNFL) thickness. DSA-derived measures included cervical segment (C1) diameter, cavernous segment (C4) diameter, stenosis percentage, ophthalmic artery (OA) filling time, C1-OA filling time, and residual stenosis. ResultsA total of 42 eyes from 30 CAS patients and 60 eyes from 30 healthy controls were included. Patients with CAS displayed significantly decreased LVD compared to controls (p < 0.001). Additionally, the CAS group had thinner choroid and RNFL (p = 0.047 and p < 0.001, respectively). Macular LVD negatively correlated with both stenosis percentage and C1-OA filling time (p = 0.010 and p = 0.014, respectively). In patients who underwent carotid artery stenting, preoperative ChT significantly correlated with residual stenosis (Pearson r = -0.480, p = 0.020). ConclusionOCT and OCTA provide a quantitative assessment of retinochoroidal microstructural changes associated with CAS, suggesting potential for noninvasive evaluation of the disease. This might contribute to the prevention of irreversible ocular complications and early detection of CAS. Furthermore, ChT may not only aid in diagnosing CAS more reliably but also offer prognostic information.

705 Urgent or Emergent Endovascular Intervention for Neurological Deficits Post-carotid Endarterectomy: A Single-institutional Case Series and Systematic Review of the Literature

INTRODUCTION: Historically the management of acute neurological deficit following carotid endarterectomy (CEA) has been operative re-exploration; however, given the proliferation of endovascular techniques, and utilization of CT angiography, endovascular intervention is an alternative to redo-CEA. METHODS: All patients undergoing CEA in the Department of Neurosurgery at Rhode Island Hospital (Providence, RI) were reviewed. A systematic literature review was conducted in PubMed according to PRISMA guidelines to identify papers relevant to endovascular procedures addressing acute neurological deficits following CEA, which yielded 2499 unique articles. Review by 2 investigators revealed 12 relevant articles. RESULTS: Four patients from our institutional cohort met inclusion criteria. Among these, stenting was technically successful in 3 patients, 2 of which achieved near-full recovery. One patient underwent successful carotid stenting and ipsilateral M2 thrombectomy for tandem occlusion. Stent placement was unsuccessful in the remaining patient due to mechanical constriction. Articles obtained through the literature review revealed 57 further relevant cases. Of those with sufficiently complete data, 30/39 (76.9%) were male with an age range of 43 - 78 years old. Twenty-eight of 32 (87.5%) patients underwent CEA for symptomatic carotid stenosis. Post-CEA angiographic evaluation was most commonly conducted for routine completion imaging (21/57, 36.8%), non-specific stroke symptoms (15/57, 26.3%), and extremity weakness (7/57, 12.3%). Thrombotic stenosis (23/43, 53.4%) and arterial dissection (15/43, 34.9%) were the most common angiography findings. Two (3.5%) stent procedures were unsuccessful, and in the immediate postoperative period 8 patients (14.0%) had significant neurological deficits and only 3 deaths (5.3%) were reported. CONCLUSIONS: Endovascular intervention may be considered in situations where patients have neurological deficit after CEA. Direct comparison of outcomes in patients who have endovascular intervention vs. redo CEA may help identify the optimal management strategy.

Transcarotid artery revascularization for in-stent restenosis complicated by flow reversal occlusion

We report a case of symptomatic high grade in-stent restenosis of a prior placed transradial carotid artery stent. We performed a Transcarotid Artery Revascularization (TCAR) to treat this symptomatic restenosis. The TCAR was complicated by occlusion of our flow reversal system by a large atherosclerotic embolus. We performed a distal common carotid cutdown to retrieve the occlusive embolus and restored flow reversal. Completion neck and cerebral angiogram showed no filling defect, and our patient showed no neurologic deficit, and resolution of pre-operative symptoms.

Safety and efficacy of early carotid artery stenting in patients with symptomatic stenosis.

Symptomatic carotid artery stenosis is a significant contributor to ischemic strokes. Carotid artery stenting (CAS) is usually indicated for secondary stroke prevention. This study evaluates the safety and efficacy of CAS performed within a short time frame from symptom onset. We conducted a single-center, retrospective study of consecutive patients who underwent CAS for symptomatic carotid stenosis within eight days of symptom onset from July 2019 to January 2022. Data on demographics, medical history, procedural details, and follow-up outcomes were analyzed. The primary outcome measure was the recurrence of the stroke within the first month post-procedure. Secondary outcomes included mortality, the rate of intra-procedural complications, and hyperperfusion syndrome. We included 93 patients with a mean age of 71.7 ± 11.7 years. The median time from symptom onset to CAS was 96 h. The rate of stroke recurrence was 5.4% in the first month, with a significant association between the number of stents used and increased recurrence risk. Mortality within the first month was 3.2%, with an overall mortality rate of 11.8% after a median follow-up of 19 months. Intra-procedural complications were present in five (5.4%) cases and were related to the number of stents used (p = 0.002) and post-procedural angioplasty (p = 0.045). Hyperperfusion syndrome occurred in 3.2% of cases. Early CAS within the high-risk window post-symptom onset is a viable secondary stroke prevention strategy in patients with symptomatic carotid artery stenosis. The procedure rate of complication is acceptable, with a low recurrence of stroke. However, further careful selection of patients for this procedural strategy is crucial to optimize outcomes.

Comparative Study of the Early and Late Results of Carotid Artery Stenting in Conditions of Hostile or Favorable Arterial Anatomy

Comparative Study of the Early and Late Results of Carotid Artery Stenting in Conditions of Hostile or Favorable Arterial Anatomy

Relationship between in-stent restenosis following carotid artery stenting and platelet reactivity to clopidogrel

ObjectiveTo analyze the relationship between in-stent restenosis (ISR) following carotid artery stenting (CAS) and platelet clopidogrel reactivity confirmed by the P2Y12 reaction unit (PRU) and inhibition rate (IR).MethodsWe retrospectively analyzed...

Changes in retinal vascular density measured by optical coherence tomography angiography in patients with carotid artery stenosis after carotid artery stenting and angioplasty.

The aim of this study was to compare the effect of carotid artery stenting and angioplasty (CASA) on retinal vascular density (VD) in patients with severe carotid stenosis with a healthy control group and to evaluate using optical coherence tomography angiography (OCTA). For this prospective study, eyes on the operated side constituted the ipsilateral eye group, and the other eye constituted the contralateral eye group. 40 eyes of 40 patients with ipsilateral eye of carotisid artery stenosis (CAS), 34 eyes on contralateral side, and 30 healthy eyes (control group) were included in this study. We performed quantitative OCTA analyses of retinal VD changes, before and after CASA. The main outcome measures were the quantitative changes of VD of superficial capillary plexus (SCP) and deep capillary plexus (DCP). We evaluated the VD of ipsilateral eyes and contralateral eyes separately before and after the procedure. All patients did not have visual symptoms. There was no significant difference in the VD of SCP in all groups before the procedure. No significant change was observed in all groups when the VD of the SCP was compared before and after the procedure. The VD of the DCP in the ipsilateral and contralateral group improved significantly after CASA. OCTA could noninvasively detect retinal VD improvements after CASA in CAS patients. Quantitative changes in VD evaluated using OCTA are thought to be early indicators in the diagnosis of CAS and in the follow-up of treatment success.

Implications of the Centers for Medicare and Medicaid Services decision to expand indications for carotid artery stenting

ObjectiveOn October 11, 2023, the Centers for Medicare and Medicaid Services (CMS) expanded the indications for carotid artery stenting (CAS) to include patients with ≥50% symptomatic or ≥70% asymptomatic carotid stenosis. The aim of this article was to investigate the implications of this decision. MethodsThe reasons behind the increased coverage for CAS are analyzed and discussed, as well as the various Societies supporting or opposing the expansion of indications for CAS. ResultsThe benefits associated with expanding CAS indications include providing an additional therapeutic option to patients and enabling individualization of treatment according to patient-specific characteristics. The drawbacks of expanding CAS indications include a possible bias in decision-making and an increase in inappropriate CAS procedures. ConclusionsThe purpose of the CMS recommendation to expand indications for CAS is to improve the available therapeutic options for patients. Hopefully this decision will not be misinterpreted and will be used to improve patient options and patient outcomes.

Determinants of Mortality and Mid-Term Outcomes After Transcarotid Artery Revascularization and Transfemoral Carotid Artery Stenting.

The potential benefit of transcarotid artery revascularization (TCAR) over transfemoral carotid artery stenting (tfCAS) has been studied in the perioperative period with lower rates of stroke and death; however, data on mid-term outcomes are limited. We aimed to evaluate 3-year outcomes after TCAR and tfCAS and determine the primary predictors of 30-day and 1-year mortality following TCAR. Data from the Vascular Quality Initiative for patients undergoing TCAR or tfCAS from January 2016 to December 2022 were analyzed. 1:1 propensity score matching using the nearest-neighbor method was used to adjust baseline demographics and clinical characteristics. Kaplan-Meier survival analysis and Cox Proportional Hazard Regression were used to evaluate long-term outcomes. Iterative stepwise multiple logistic regression analysis and Cox Proportional Hazard Regression were used to identify predictors of 30-day and 1-year mortality, respectively, based upon preoperative, intraoperative, and postoperative factors. A total of 70 237 patients were included in analysis (TCAR=58.7%, tfCAS=41.3%). Transcarotid artery revascularization patients were older and had higher rates of comorbid conditions and high-risk medical and anatomic features than tfCAS patients. Propensity score matching yielded 22 322 pairs with no major differences between groups except that TCAR patients were older (71.6 years vs 70.8 years). At 3 years, TCAR was associated with a 24% reduction in hazard of death compared with tfCAS (hazard ratio [HR]=0.76, 95% confidence interval [CI]=0.71-0.82, p<0.001), for both symptomatic and asymptomatic patients. This survival advantage was established in the first 6 months (HR=0.59, 95% CI=0.53-0.62, p<0.001), with no difference in mortality risk from 6 months to 36 months (HR=0.95, 95% CI=0.86-1.05, p=0.31). Transcarotid artery revascularization was also associated with decreased hazard for 3-year stroke (HR=0.81, 95% CI=0.66-0.99, p=0.04) and stroke or death (HR=0.81, 95% CI=0.76-0.87, p<0.001) compared with tfCAS. The top predictors for 30-day and 1-year mortality were postoperative complications. The primary independent predictor was the occurrence of postoperative stroke. Transcarotid artery revascularization had a sustained mid-term survival advantage associated over tfCAS, with the benefit being established primarily within the first 6 months. Notably, our findings highlight the importance of postoperative stroke as the primary independent predictor for 30-day and 1-year mortal. The ongoing debate over the superiority of TCAR compared to tfCAS and CEA has been limited by a lack of comparative studies examining the impact of pre-operative symptoms on outcomes. Furthermore, data are scarce on mid-term outcomes for TCAR beyond the perioperative period. As a result, it remains uncertain whether the initial benefits of stroke and death reduction observed with TCAR over tfCAS persist beyond one year. Our study addresses these gaps in the literature, offering evidence to enable clinicians to assess the efficacy of TCAR for up to three years. Additionally, our study seeks to identify risk factors for postoperative mortality following TCAR, facilitating optimal patient stratification.

Patient decision-making in the era of transcarotid artery revascularization

ObjectiveThe National Coverage Determination on carotid stenting by Medicare in October 2023 stipulates that patients participate in a shared decision-making (SDM) conversation with their proceduralist before an intervention. However, to date, there is no validated SDM tool that incorporates transcarotid artery revascularization (TCAR) into its decision platform. Our objective was to elicit patient and surgeon experiences and preferences through a qualitative approach to better inform the SDM process surrounding carotid revascularization. MethodsWe performed longitudinal perioperative semistructured interviews of 20 participants using purposive maximum variation sampling, a qualitative technique designed for identification and selection of information-rich cases, to define domains important to participants undergoing carotid endarterectomy or TCAR and impressions of SDM. We also performed interviews with nine vascular surgeons to elicit their input on the SDM process surrounding carotid revascularization. Interview data were coded and analyzed using inductive content analysis coding. ResultsWe identified three important domains that contribute to the participants' ultimate decision on which procedure to choose: their individual values, their understanding of the disease and each procedure, and how they prefer to make medical decisions. Participant values included themes such as success rates, “wanting to feel better,” and the proceduralist's experience. Participants varied in their desired degree of understanding of carotid disease, but all individuals wished to discuss each option with their proceduralist. Participants' desired medical decision-making style varied on a spectrum from complete autonomy to wanting the proceduralist to make the decision for them. Participants who preferred carotid endarterectomy felt outcomes were superior to TCAR and often expressed a desire to eliminate the carotid plaque. Those selecting TCAR felt it was a newer, less invasive option with the shortest procedural and recovery times. Surgeons frequently noted patient factors such as age and anatomy, as well as the availability of long-term data, as reasons to preferentially select one procedure. For most participants, their surgeon was viewed as the most important source of information surrounding their disease and procedure. ConclusionsSDM surrounding carotid revascularization is nuanced and marked by variation in patient preferences surrounding autonomy when choosing treatment. Given the mandate by Medicare to participate in a SDM interaction before carotid stenting, this analysis offers critical insights that can help to guide an efficient and effective dialog between patients and providers to arrive at a shared decision surrounding therapeutic intervention for patients with carotid disease.

Analysis of the therapeutic effect of aspiration thrombectomy for early carotid stent thrombosis

Objective: To investigate the clinical characteristics and the efficacy of thrombus aspiration in patients with early intrastent thrombosis (EST) following carotid artery stenting (CAS). Methods: This study is a retrospective case series, collecting clinical data of five patients who developed EST after CAS in the Department of Neurosurgery, Beijing Chaoyang Hospital, Capital Medical University from January 2021 to September 2023.All patients were male, with an age of (64.0±11.9) years (range:48 to 77 years), accounting for 2.0% (5/244) of CAS procedures during the same period.Among them, three patients did not receive standard dual antiplatelet therapy before the procedure, and one had an inadequate ADP inhibition rate (45.6%).Four patients received XACT carotid stents, while one received a Wallstent carotid stent.All five patients showed significant residual stenosis ranging from 43% to 55% after CAS.Emergency thrombus aspiration was performed in all cases, and data regarding perioperative conditions, vascular patency, and clinical outcomes were collected. Results: The interval between CAS and the occurrence of EST ranged from 3 hours to 14 days.The main clinical symptoms included sudden onset of consciousness disorders and contralateral limb weakness.None of the patients received preoperative intravenous thrombolysis, and thrombus aspiration was performed during the procedure to restore vascular patency.Four cases underwent balloon angioplasty during the procedure, and two cases utilized overlapping stents.Two patients experienced intraoperative embolization of thrombus to the C2 segment.In one case, the embolized thrombus was retrieved using an intracranial thrombectomy stent, while in another case, it was aspirated using a guiding catheter.Postoperatively, all patients had a thrombolysis in cerebral infarction grade of 3, and symptoms improved in four cases.One patient showed no improvement in symptoms, and MRI revealed extensive new infarction in the right frontal and insular regions, adjacent to the right lateral ventricle.Regular follow-up examinations after discharge did not reveal restenosis or embolism within the stent.The follow-up period ranged from 7.6 to 21.2 months, with modified Rankin scale scores of 0 to 1 point in four cases and 2 points in one case, indicating good recovery in all patients. Conclusions: Acute intrastent thrombosis is a rare complication after carotid artery stenting.The combined use of percutaneous thrombus aspiration and endovascular techniques, such as balloon angioplasty and stent overlapping, can rapidly restore vessel patency with favorable outcomes.However, further large-scale clinical studies are needed to confirm the effectiveness of these treatments for acute intrastent thrombosis.

Carotid Artery Stenting

Currently, stricter indications for carotid artery stenosis are required owing to improvements in multifaceted medical treatment, including the intensive management of risk factors for atherosclerosis and lifestyle changes. High-risk factors for carotid artery stenting, such as vulnerable plaques, severe calcification, pseudo-occlusion, and difficult access, should be evaluated before endovascular intervention. Therefore, we need to understand the characteristics of each device to achieve maximum risk reduction for carotid artery stenting.

Learning curve of transfemoral carotid artery stenting in the Vascular Quality Initiative registry

ObjectiveWith the recent expansion of the Centers for Medicare and Medicaid Services coverage, transfemoral carotid artery stenting (tfCAS) is expected to play a larger role in the management of carotid disease. Existing research on the tfCAS learning curve, primarily conducted over a decade ago, may not adequately describe the current effect of physician experience on outcomes. Because approximately 30% of perioperative strokes/deaths post-CAS occur after discharge, appropriate thresholds for in-hospital event rates have been suggested to be <4% for symptomatic and <2% for asymptomatic patients. This study evaluates the tfCAS learning curve using Vascular Quality Initiative (VQI) data. MethodsWe identified VQI patients who underwent tfCAS between 2005 and 2023. Each physician's procedures were chronologically grouped into 12 categories, from procedure counts 1-25 to 351+. The primary outcome was in-hospital stroke/death rate; secondary outcomes were in-hospital stroke/death/myocardial infarction (MI), 30-day mortality, in-hospital stroke/transient ischemic attack (stroke/TIA), and access site complications. The relationship between outcomes and procedure counts was analyzed using the Cochran-Armitage test and a generalized linear model with restricted cubic splines. Our results were then validated using a generalized estimating equations model to account for the variability between physicians. ResultsWe analyzed 43,147 procedures by 2476 physicians. In symptomatic patients, there was a decrease in rates of in-hospital stroke/death (procedure counts 1-25 to 351+: 5.2%-1.7%), in-hospital stroke/death/MI (5.8%-1.7%), 30-day mortality (4.6%-2.8%), in-hospital stroke/TIA (5.0%-1.1%), and access site complications (4.1%-1.1%) as physician experience increased (all P values < .05). The in-hospital stroke/death rate remained above 4% until 235 procedures. Similarly, in asymptomatic patients, there was a decrease in rates of in-hospital stroke/death (2.1%-1.6%), in-hospital stroke/death/MI (2.6%-1.6%), 30-day mortality (1.7%-0.4%), and in-hospital stroke/TIA (2.8%-1.6%) with increasing physician experience (all P values <.05). The in-hospital stroke/death rate remained above 2% until 13 procedures. ConclusionsIn-hospital stroke/death and 30-day mortality rates after tfCAS decreased with increasing physician experience, showing a lengthy learning curve consistent with previous reports. Given that physicians' early cases may not be included in the VQI, the learning curve was likely underestimated. Nevertheless, a substantially high rate of in-hospital stroke/death was found in physicians' first 25 procedures. With the recent Centers for Medicare and Medicaid Services coverage expansion for tfCAS, a significant number of physicians would enter the early stage of the learning curve, potentially leading to increased postoperative complications.

Uncommon Carotid Artery Stenting Complications: A Series by Images.

To describe through emblematic images rare but clinically relevant carotid artery stenting complications that occurred at two high-volume centres for carotid artery stenting (CAS). CAS is an alternative to carotid endarterectomy (CEA) for the treatment of carotid artery stenosis in patients judged to be at high risk for CEA. CAS complications range between 1 and 9% and are higher in older patients complaining of neurological symptoms at the time of presentation. Besides periprocedural or early-after-procedure stroke, which remains the true Achilles' heel of CAS, other dramatic complications might compromise the clinical outcomes of this procedure. Five infrequent complications, out of more than 1000 CAS performed in the years 2016-2021, have been described. Among CAS complications, acute carotid stent thrombosis, rescue retrieval of a disconnected distal cerebral embolic protection device, plaque prolapse after carotid stenting, cerebral hyperperfusion syndrome (CHS), and radial artery long sheath entrapment requiring surgical intervention were found to account for 0.3% of the total number of procedures performed by operators with high CAS volume. Unusual CAS complications may infrequently occur, even in hands of expert operators. To know how to deal with such complications might help interventionalists to improve CAS performance.

Flow arrest during carotid artery stenting with a distal embolic protection device: A single-center experience and clinical implications.

We aimed to investigate the incidence of flow arrest during carotid artery stenting (CAS) with filter-type embolic protection device (EPD), identify any predisposing factors for those situations, and contemplate intraprocedural precautionary steps. CAS was performed in 128 patients with 132 arteries using filter-type EPD. The characteristics of treated patients and arteries were compared between groups with and without flow arrest. The incidence of flow arrest during CAS with filter-type EPD was 17.4%. In flow arrest group, cases of vulnerable plaques (p=0.02) and symptomatic lesions (p=0.01) were significantly more common, and there were more cases of debris captured by EPD in a planar pattern (p<0.01). Vulnerable plaques were significantly more common in the procedures showing a planar pattern than in the cases with other patterns (p<0.01). Flow arrest group showed a significantly higher rate of ischemic complications (p<0.05), although there were no significant periprocedural neurological changes. The planar pattern of captured debris in filter-type EPD was the only significant risk factor for flow arrest (adjusted odds ratio 88.44, 95% confidence interval 15.21-514.45, p<0.05). Flow arrest during CAS with filter-type EPD is not uncommon and associated with increased ischemic complications. Symptomatic stenoses and vulnerable plaque are related to this event. The planar pattern of captured debris on the EPD was the only significant risk factor for the flow arrest. Clinicians must pay attention to the occurrence of flow arrest and react quickly when performing CAS.

Value of intravenous alteplase before thrombectomy among patients with tandem lesions and emergent carotid artery stenting: A subgroup analysis of the SWIFT DIRECT trial.

The value of intravenous thrombolysis (IVT) in eligible tandem lesion patients undergoing endovascular treatment (EVT) is unknown. We investigated treatment effect heterogeneity of EVT + IVT versus EVT-only in tandem lesion patients. Additional analyses were performed for patients undergoing emergent internal carotid artery (ICA) stenting. SWIFT DIRECT randomized IVT-eligible patients to either EVT + IVT or EVT-only. Primary outcome was 90-day functional independence (modified Rankin Scale score 0-2) after the index event. Secondary endpoints were reperfusion success, 24 h intracranial hemorrhage rate, and 90-day all-cause mortality. Interaction models were fitted for all predefined outcomes. Among 408 included patients, 63 (15.4%) had a tandem lesion and 33 (52.4%) received IVT. In patients with tandem lesions, 20 had undergone emergent ICA stenting (EVT + IVT: 9/33, 27.3%; EVT: 11/30, 36.7%). Tandem lesion did not show treatment effect modification of IVT on rates of functional independence (tandem lesion EVT + IVT vs. EVT: 63.6% vs. 46.7%, non-tandem lesion EVT + IVT vs. EVT: 65.6% vs. 58.2%; p for interaction = 0.77). IVT also did not increase the risk of intracranial hemorrhage among tandem lesion patients (tandem lesion EVT + IVT vs. EVT: 34.4% vs. 46.7%, non-tandem lesion EVT + IVT vs. EVT: 33.5% vs. 26.3%; p for interaction = 0.15). No heterogeneity was noted for other endpoints (p for interaction > 0.05). No treatment effect heterogeneity of EVT + IVT versus EVT-only was observed among tandem lesion patients. Administering IVT in patients with anticipated emergent ICA stenting seems safe, and the latter should not be a factor to consider when deciding to administer IVT before EVT.