Internal Carotid Artery Stenosis Research Articles

Change in Peak Systolic Velocity Estimation in Internal Carotid Artery Following Contralateral Near Occlusive Carotid Endarterectomy

Carotid artery stenosis (CAS) is one of the main causes of stroke, as the internal carotid artery (ICA) is a major source of cerebral blood supply. A common surgical intervention for CAS is carotid endarterectomy (CEA), which carries a high risk of stroke and mortality. CEA is indicated for 50% to 99% stenosis in symptomatic patients and 60% to 99% stenosis in asymptomatic patients. Carotid duplex ultrasound is frequently used to estimate peak systolic velocity (PSV), end diastolic velocity (EDV), and ICA/common carotid artery (CCA) ratio to determine the extent of stenosis. This does not account for other factors that can artificially change PSV and EDV, such as a contralateral carotid artery near occlusion with >90% stenosis. Although >70% contralateral stenosis has been previously studied, limited research exists on the impact of ICA near occlusions. We hypothesize that the degree of stenosis in an ipsilateral patent vessel can be more accurately estimated by examining the change in PSV pre- vs post-CEA of the contralateral ICA near occlusion. A retrospective study was conducted on 239 patients, at least 18 years of age, who underwent standard, routine carotid duplex ultrasound at a single institution. Patients who qualified for the study had bilateral carotid stenosis with ICA near occlusive disease on at least one side and underwent CEA. Near occlusion was determined by either a carotid duplex ultrasound >70% with one of the following criteria: PSV >400, EDV >140, or ratio of ICA/CCA >6, or a carotid computed tomography angiography showing near occlusion interpreted by a physician. Preoperative duplex velocities contralateral to the CEA were recorded and compared postoperatively. Interestingly, in the presence of contralateral >50% ICA stenosis, the PSV, EDV, and ICA/CCA ratio in the unoperated artery increased significantly following contralateral CEA (P < .001). In greater than 70% contralateral ICA occlusion, PSV, EDV, and ICA/CCA ratio increased to a greater extent compared with >50% contralateral ICA stenosis (P < .001). In detecting ≥70% stenosis of the patent vessel pre-CEA, PSV ≥250 cm/s had 87.2% sensitivity. In predicting ≥70% stenosis of the patent vessel pre-CEA, PSV >300 cm/s had 96.0% sensitivity. The present study deviates from the current theoretical model and shows that ultrasound PSV, EDV, ICA/CCA ratios can be significantly elevated in the patent vessel pre-CEA and post-CEA of the contralateral ICA near occlusion. This study provides novel insight into customized duplex ultrasound criteria for estimation of stenosis and to avoid unnecessary high-risk surgery.

Timing and Outcomes of Precoronary Artery Bypass Grafting Carotid Endarterectomy

The Society for Vascular Surgery Clinical Practice Guidelines suggests the timing of carotid endarterectomy (CEA) in patients with symptomatic or bilateral severe asymptomatic carotid stenosis needing coronary artery bypass grafting (CABG) be performed either with preoperative CEA or concomitantly with CABG. The optimal timing of CEA in patients with high grade unilateral stenosis, however, has been controversial due to equivocal and/or scarce data. This study examines our experience with pre-CABG CEA and timing in this patient population. This is a single-center retrospective review of all patients who underwent CEA before or during CABG between January 2010 and January 2021. All patients receiving CEA were anesthetized by a dedicated cardiac anesthesiologist. Patients were compared based on timing of CEA in relation to CABG: concomitant (CABG day 0 from CEA) and nonconcomitant (CABG day 1-30 after CEA). The nonconcomitant cohort was substratified into hyperacute (CABG within 48 hours), acute (CABG within 2 weeks), and subacute (CABG within 30 days). Demographics and status of carotid disease were collated. Primary outcomes included stroke, defined as new neurologic deficit, myocardial infarction (MI), 30-day readmission, and 30-day mortality. A total of 39 patients were identified in the study population. Of these, 9 (23%) patients underwent CEA and CABG concomitantly, with 30 receiving nonconcomitant CEA (hyperacute [9, 23%]; acute [16, 41%]; subacute [5, 13%]). Baseline demographics and comorbidities were similar between groups. The degree of internal carotid artery stenosis, presence of high-grade contralateral stenosis, and symptomatic carotid presentation did not impact perioperative outcomes. One stroke occurred after a concomitant CEA/CABG that was a bi-hemispheric event believed to be due to cannulating a highly diseased ascending aorta. One patient in the concomitant cohort developed postoperative MI, cardiogenic shock, and subsequent death (Table I). There was no observed stroke, MI, or death in the nonconcomitant cohort. Thirty-day readmission and mortality were similar between all groups (Tables I and II). However, when comparing aggregate stoke/MI (Table I), a statistically significant difference was observed in favor of the nonconcomitant cohort (P = .007). Careful consideration is needed when determining appropriate timing for coronary revascularization in patients with carotid disease. These data suggest that nonconcomitant, preoperative CEA can be performed safely by a dedicated cardiac anesthesiologist before CABG. Concomitant CEA/CABG, as reflected in these data, carries an added procedural risk of stroke and a potentially poor cardiac outcome. Further study is warranted to elucidate the role of timing in perioperative outcomes for patients requiring CEA and CABG.Table IPerioperative outcomes for patients undergoing coronary artery bypass grafting (CABG) within 30 days of carotid endarterectomy (CEA)Concomitant CABG (n = 9)Nonconcomitant CABG (n = 30)P valuePostoperative events (MI, NS), No. (%)2 (22.2)0 (0).007a30-day readmission, No. (%)1 (11.1)3 (10).9330-day mortality, No. (%)1 (11.1)0 (0).07MI, Myocardial infarction; NS, neurologic symptoms. Open table in a new tab Table IIPerioperative outcomes for patients undergoing coronary artery bypass grafting (CABG) within 30 days of carotid endarterectomy (CEA), with the nonconcomitant CEA/CABG cohort substratified by timingConcomitant CABG (n = 9)Hyperacute CABG (n = 9)Acute CABG (n = 16)Subacute CABG (n = 5)P valuePostoperative events (MI, NS), No. (%)2 (11.1)0 (0)0 (0)0 (0).3530-day readmission, No. (%)1 (11.1)0 (0)1 (6.3)2 (40).1130-day mortality, No. (%)1 (11.1)0 (0)0 (0)0 (0).35MI, Myocardial infarction; NS, neurologic symptoms. Open table in a new tab

Internal carotid artery stenosis: hemodynamics in the ipsilateral ACA affects CT angiography manifestations.

This study aimed to evaluate whether CT angiography (CTA) manifestations in anterior cerebral artery a1 segment (A1) were related to the hemodynamics in patients with internal carotid artery stenosis (ICAS). A total of 97 cases were selected. The degree of ICAS and symmetry of A1 were evaluated by CTA examination. Hemodynamic indexes were detected by transcranial Doppler (TCD). The differences in CTA presentations of A1 and hemodynamics between the vessels on the stenotic and contralateral sides were analyzed according to the different degrees of stenosis. The degree of ICAS according to the different manifestations of A1 and the hemodynamics of A1's adjacent vessels were also analyzed. In the case of unilateral ICAS, the difference in Vm of A1 between the stenotic and the contralateral side was the most significant relative to the stenosis degree. When unilateral ICAS was ≥70%, the presentation of A1 on the stenotic side was more slender or non-visualized compared to that on the contralateral side, while in cases with unilateral stenosis <70% or bilateral stenosis with a similar degree of stenosis, A1 were mainly symmetrical. When A1 on the side of ICAS was slender or non-visualized, the Vm of A1 was significantly slower than that on the contralateral side (P < 0.001). The CTA manifestations of A1 on the side of ICAS embodied the overall changes of the intracranial hemodynamics after ICAS. A combination of TCD and CTA examination of A1 can assist in judging the location and degree of ICAS.

Balloon-Assisted Catheterization of Occluded Carotid Artery (BOCA) Technique in Acute Stroke.

Acute ischemic stroke from tandem occlusion of internal carotid artery (ICA) poses a technical challenge to neurointerventionalists. To present a novel balloon-assisted catheterization of occluded carotid artery (BOCA) technique used for rapid and effective catheterization of occluded/critically stenosed ICA in tandem occlusion. A retrospective review of 10 patients with tandem carotid occlusion, treated with BOCA technique for revascularization between July 2020 and June 2021, was performed. Clinical, radiographic, and procedural data; details of BOCA technique; complications; and outcomes were reviewed. Of the 10 patients, 8 (80%) had complete occlusion of the cervical ICA and the remaining 2 had high-grade stenosis with poor intracranial flow. The mean age was 63.2 years. The mean presenting NIH Stroke Scale was 13.4. The BOCA technique resulted in recanalization of ICA in all patients and allowed mechanical thrombectomy of middle cerebral artery. Thrombolysis in cerebral infarction grade 2b/3 was achieved in all 10 patients. The mean groin-to-reperfusion time was 41.4 minutes. The mean internal carotid artery stenosis was 99.7% preoperatively and 41.1% postoperatively. Only one patient needed stent at the end of the procedure because of dissection. The BOCA technique can be used in distal first approach for acute stroke from tandem ICA occlusion. This technique allows direct guide catheterization of occluded ICA by tracking over a partially inflated balloon.

Concomitant occurrence of Cerebral Hyperperfusion Syndrome (CHS) and Reversible Cerebral Vasoconstriction Syndrome (RCVS) after right Carotid Endarterectomy (CEA) (P2-5.018)

<h3>Objective:</h3> To describe an interesting case of CHS and RCVS occurring concomitantly following CEA <h3>Background:</h3> Both CHS and RCVS are known complications of CEA. On rare occasions both complications can occur concomitantly after CEA. <h3>Design/Methods:</h3> Case report <h3>Results:</h3> A 58-year-old female with long-standing history of smoking and hyperlipidemia presented to outside hospital (OSH) with pressure-like headache on top of her head and feeling of facial swelling. CT angiogram of head and neck (CTA) showed right internal carotid artery (ICA) stenosis of 85% and left ICA stenosis of 80%. Three months after the initial presentation she underwent right CEA. Immediately following procedure, she had severe throbbing headache on right side which responded to Toradol. Neurologic examination was otherwise unremarkable, and she was discharged home on dual anti-platelet therapy. After discharge, she continued to have headache. Ten days after the procedure, she developed left sided weakness and presented to an outside hospital where she had a seizure and was started on levetiracetam. MRI of the brain showed edematous changes on the right consistent with CHS without evidence of acute stroke. Right ICA was patent and there was segmental vasoconstriction and dilation of cerebral vasculature consistent with RCVS. Due to increased risk of hemorrhagic strokes with CHS and RCVS, left CEA was not recommended and maximal medical therapy was recommended. There was resolution of edematous changes in right cerebral hemisphere on MRI two months later. CTA at two months follow up showed resolution of segmental vasoconstriction and vasodilation, patent right ICA and unchanged left ICA stenosis. <h3>Conclusions:</h3> CHS and RCVS can occur concomitantly after CEA and can lead to devastating hemorrhagic strokes. In patients who develop CHS and RCVS concomitantly maximal medical therapy should be recommended for contralateral ICA stenosis. <b>Disclosure:</b> Dr. Anjum has nothing to disclose. Dr. Burton has nothing to disclose. Dr. Javalkar has nothing to disclose. Dr. Chernyshev has nothing to disclose.

Lemierre syndrome associated Cavernous Sinus Thrombosis and Development of Internal Carotid Artery Narrowing: A Case Report and Review of Literature (P2-5.005)

<h3>Objective:</h3> To report a case of Lemierre syndrome complicated by cavernous sinus thrombosis (CST) and bilateral internal carotid artery (ICA) stenosis without cerebral infarction in a young woman and summarize the literature on Lemierre syndrome with arterial involvement. <h3>Background:</h3> Lemierre syndrome is a complication of oropharyngeal infection characterized by thrombosis of the internal jugular vein (IJV) with septic thrombophlebitis followed by bacteremia and septic emboli dissemination to distal organs, but arterial involvement is extremely rare. <h3>Design/Methods:</h3> A 24-year-old previously healthy woman presented to the hospital with one week of progressive jaw pain and neck swelling after recent tooth extraction. Physical examination showed left ptosis without other neurologic deficits. Computer tomography (CT) of the neck found multiple anterior neck abscesses. The patient underwent emergent incision and drainage of abscess at the left lateral pharyngeal, left masticator, and bilateral sublingual space. Vascular imaging revealed findings of non-occlusive thrombus in the left IJV, bilateral cavernous sinus thrombosis (CST), and septic emboli in bilateral apical lungs, consistent with Lemierre syndrome. Neuroimaging showed no cerebral infarction even though a digital subtraction angiogram (DSA) demonstrated bilateral ICA severe stenosis (&gt;70%) in both extracranial and intracranial segments. Cultures of abscess samples proved positive for <i>Candida albicans</i> and <i>Streptococcus constellatus</i>. The patient received treatment with full-coverage antibiotics and anticoagulation therapy resulting in an excellent outcome. <h3>Results:</h3> A literature search yielded 29 cases of Lemierre syndrome with arterial complications, which manifested as ICA occlusion or stenosis, or mycotic aneurysm development. Despite variable clinical symptoms, most patients developed CST and were all treated with antibiotics. Anticoagulation therapy is controversial given scarce and inconsistent evidence. <h3>Conclusions:</h3> The presented case and literature review emphasize the variability of the clinical course of Lemierre syndrome. Septic CST can be a rare cause of ICA occlusion, stenosis, or pseudoaneurysms because of arteritis, and thus expedited workup is necessary. <b>Disclosure:</b> Dr. Zhou has nothing to disclose. Dr. Malik has nothing to disclose.

The Many Manifestations of Rhino-Orbital-Cerebral Mucormycosis: An Illustrative Case Report (P10-10.003)

<h3>Objective:</h3> To describe and illustrate with neuroimaging the progression of rhino-orbital-cerebral mucormycosis leading to orbital apex syndrome, cranial neuropathies, cavernous sinus thrombosis, and strokes from internal carotid artery steno-occlusive disease. <h3>Background:</h3> A 67-year old female with uncontrolled diabetes mellitus presented with progressive vision loss in the right eye and right sided facial weakness, associated with fatigue and fevers. She underwent intranasal debridement, and hematoxylin and eosin staining showed broad-based, branching, non-septate hyphae, consistent with mucormycosis. She was treated with antifungals. She sought care again 3 months later, at which point she had no vision in the right eye, and was unable to open or move the right eye. Her examination at this point was notable for no light perception in the right eye with mid-size, unreactive pupil; complete ptosis and ophthalmoplegia of the right eye; and right facial weakness in a lower motor neuron pattern. Magnetic resonance imaging of the brain demonstrated inflammation at the orbital apex, as well as thromboses of the right superior ophthalmic vein and right cavernous sinus. Despite treatment with systemic antifungals and anticoagulation, the patient later developed sudden-onset lethargy associated with a right gaze deviation. She was found to have severe stenosis of the bilateral intracranial internal carotid arteries on cerebral angiogram. Magnetic resonance imaging showed interval development of bilateral deep watershed territory infarcts. <h3>Design/Methods:</h3> NA <h3>Results:</h3> NA <h3>Conclusions:</h3> Mucormycosis is a rare but devastating fungal infection caused by mucormycetes, which are ubiquitous in nature. Most patients with invasive mucormycosis are immunocompromised, classically due to poorly controlled diabetes or hematologic malignancies. Mucormycosis spreads contiguously through the sinuses, and is also angioinvasive. Because the infection typically begins as a rhinosinusitis, the fungus spreads intracranially through direct invasion of the cavernous sinus. This case and the associated imaging illustrates the stepwise progression of mucormycosis due to contiguous spread intracranially. <b>Disclosure:</b> Dr. Trenz has nothing to disclose. Dr. Tetreault has nothing to disclose.

Case of a Pure Arterial Malformation and Review of the Literature. (P12-5.029)

<h3>Objective:</h3> NA <h3>Background:</h3> Pure arterial malformations are dilated, overlapping, and tortuous arteries forming a mass of arterial loops without a venous component. These malformations are rare, with limited cases reported in the literature. Affecting any of the intracranial arteries, they are usually found incidentally and often have a benign course. <h3>Design/Methods:</h3> We present a case of a pure arterial malformation in a young female with hyperprolactinemia. Furthermore, we review the literature and provide an updated summary of these malformations. <h3>Results:</h3> A 28-year-old female with a history of infantile hemangiomas, polycystic ovary syndrome, and hyperprolactinemia presented with acne, mild hirsutism, and galactorrhea. Her neurological exam was normal. Magnetic Resonance Imaging (MRI) of the brain with and without contrast ruled out a prolactinoma but revealed a 3 cm vascular malformation at the margin of the left cavernous sinus extending posteriorly into the anterior left perimesencephalic cistern. Initial differentials included a pial arteriovenous malformation or less likely a dural arteriovenous fistula. A diagnostic cerebral angiogram revealed a pure arterial malformation without arteriovenous shunting. This was composed of dysplasia of the left posterior communicating artery and anterior choroidal arteries. Stenosis of the left internal carotid artery distally with collateral support into the left anterior cerebral artery and middle cerebral artery was also noted. Genetic testing for vascular malformation syndromes, including genes known to be associated with hereditary hemorrhagic telangiectasia, was negative. Repeat MRI/MRA done 8 months from the initial scan revealed no abnormal large arterial venous shunting or definite saccular aneurysm formation. <h3>Conclusions:</h3> Although rare, pure arterial malformations should be considered in the differential diagnosis for patients presenting with a cranial vascular malformation. Management of these lesions is usually conservative given their lack of arteriovenous shunting and low risk of rupture, with only a few cases undergoing surgery or endovascular treatment. <b>Disclosure:</b> Dr. Ahmed has nothing to disclose. Dr. Regenhardt has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Rapid Medical. Dr. Regenhardt has received personal compensation in the range of $500-$4,999 for serving as an Expert Witness for Johnson and Bell Trial Lawyers. The institution of Dr. Regenhardt has received research support from National Institutes of Health. The institution of Dr. Regenhardt has received research support from Society of Vascular and Interventional Neurology. The institution of Dr. Regenhardt has received research support from Heitman Foundation. Dr. Vranic has nothing to disclose. Dr. Dmytriw has nothing to disclose. James D. Rabinov has stock in Pfizer.

Effect of Antiplatelet Therapy in Acute Ischemic Stroke with Tandem Lesions (P7-5.001)

Effect of Antiplatelet Therapy in Acute Ischemic Stroke with Tandem Lesions (P7-5.001)

Intraoperative Neuromonitoring of Hypoglossal Nerves Using Transcranial and Direct Electrical Stimulation During Extracranial Internal Carotid Artery Surgery.

We explored whether the electromyogram (EMG) and the motor evoked potential (MEP) are useful for monitoring the function of the hypoglossal nerve during surgery targeting the cervical segment of the internal carotid artery. The present study included 6 patients with internal carotid arterial stenosis (1 patient underwent bilateral surgeries) and 1 patient with a cervical carotid artery aneurysm. In 5 of the 8 procedures, the EMGs were recorded. We examined whether changes in the MEP and/or EMG were capable of predicting postoperative hypoglossal nerve deficits. None of the 6 patients who underwent a total of 7 carotid endarterectomy (CEA) procedures experienced postoperative hypoglossal nerve morbidity. In 2 of the 7 procedures, the MEP disappeared or decreased significantly during CEA. In all 4 cases in which the hypoglossal nerve was directly stimulated during CEA, stable and reproducible EMGs were obtained throughout the manipulation of the internal carotid artery. Hypoglossal nerve morbidity was observed in the one case that underwent aneurysm removal and end-to-end anastomosis of the internal carotid artery. In this case, while the MEP decreased significantly during the operation, the EMG showed true-positive results and false-negative results, depending on the stimulation site. The monitoring of hypoglossal nerve function using EMG appears to be accurate if an appropriate stimulation site is selected. Hypoglossal nerve monitoring using MEP can produce false-positive results. Combined monitoring using both MEP and EMG is recommended in cases where exposure of the hypoglossal nerve is expected to be technically difficult.

Reduced-order modeling and analysis of dynamic cerebral autoregulation via diffusion maps

Objective. A data-driven technique for parsimonious modeling and analysis of dynamic cerebral autoregulation (DCA) is developed based on the concept of diffusion maps. Specifically, first, a state-space description of DCA dynamics is considered based on arterial blood pressure, cerebral blood flow velocity, and their time derivatives. Next, an eigenvalue analysis of the Markov matrix of a random walk on a graph over the dataset domain yields a low-dimensional representation of the intrinsic dynamics. Further dimension reduction is made possible by accounting only for the two most significant eigenvalues. The value of their ratio indicates whether the underlying system is governed by active or hypoactive dynamics, indicating healthy or impaired DCA function, respectively. We assessed the reliability of the technique by considering healthy individuals and patients with unilateral internal carotid artery (ICA) stenosis or occlusion. We computed the sensitivity of the technique to detect the presumed side-to-side difference in the DCA function of the second group (assuming hypoactive dynamics on the occluded or stenotic side), using McNemar’s chi square test. The results were compared with transfer function analysis (TFA). The performance of the two methods was also compared under the assumption of missing data. Main results. Both diffusion maps and TFA suggested a physiological side-to-side difference in the DCA of ICA stenosis or occlusion patients with a sensitivity of 81% and 71%, respectively. Further, both two methods suggested the difference between the occluded or stenotic side and any two sides of the healthy group. However, the diffusion maps captured additional difference between the unoccluded side and the healthy group, that TFA did not. Furthermore, compared to TFA, diffusion maps exhibited superior performance when subject to missing data. Significance. The eigenvalues ratio derived using the diffusion maps technique can be potentially used as a reliable and robust biomarker for assessing how active the intrinsic dynamics of the autoregulation is and for indicating healthy versus impaired DCA function.

5613251 RAPIDLY PROGRESSING MOYAMOYA SYNDROME IN SICKLE CELL DISEASE -- CASE REPORT

Introduction: Moyamoya syndrome (MMS) is an uncommon cerebrovascular complication of Sickle Cell Disease (SCD) characterized by progressive narrowing of large intracranial vessels and development of small-vessel collaterals. This association leads to a significant risk of ischemic stroke and poor neurologic outcomes. Case description: We present a case of a 5-year-old female child, with irregular follow-up at Pediatric Hematology Consultation due to Sickle Cell Disease, who presented to our hospital with a first ischemic stroke. The magnetic resonance angiography (MRA) showed narrowing of the terminal portions of the right internal carotid artery, the proximal segments of the right middle and anterior cerebral arteries and the A1 segment of left anterior cerebral artery, with multiple collaterals, aspects highly suggestive of MMS. She initiated hydroxycarbamide, acetylsalicylic acid and chronic red blood cell exchange (RBCX) aiming HbS<30% and 3 months later she presented with a new transient ischemic stroke. She was submitted to right encephaloduroarteriosynangiosis (EDAS) and was stable, without new ischemic events, until 1 year later when she presented with a new transient ischemic stroke of the left cerebral territory. Since then, she had multiple recurrent ischemic events with total recovery of neurologic deficits. MRA and Computed tomography (CT) showed multiple diffuse areas of cerebral infarction and bilateral severe segmental stenosis of internal carotid, middle and anterior cerebral arteries. Discussion/Conclusion: The literature review suggests that early detection and surgical revascularization in addition to RBCX could significantly reduce stroke recurrence and improve neurocognitive outcome. However, in this case, despite the recommended treatment, it was not possible to prevent the rapid progression of MMS, revealing the complexity of the approach to these patients.

Cerebral hyperperfusion syndrome after stenting for revascularization of intracranial internal carotid artery dissection

Cerebral hyperperfusion syndrome (CHS) is one of the complications of cerebral revascularization. The main pathophysiology of CHS was considered to be cerebral autoregulation impairment due to long-standing cerebral hypoperfusion. Herein, we describe the case of a 40-year-old man with symptomatic intracranial arterial dissection (IAD) related to internal carotid artery stenosis. The patient underwent intracranial stenting 11 days after onset due to severe cerebral hypoperfusion presenting with neurological symptoms, and CHS presenting with intracerebral hemorrhage, post-operatively. The present case indicated not only the potential risk of CHS after intracranial stenting in IAD-related stenosis but also that cerebral hypoperfusion-even in a short period-might lead to CHS.

390 Real World Analysis of Outcomes After Revascularization Surgery for Symptomatic Non-stenotic Carotid (SyNC) Artery Disease

INTRODUCTION: Symptomatic non-stenotic carotid (SyNC) artery disease is emerging as one of the primary causes of embolic stroke of unknown source. The optimal secondary prevention strategies including medical therapy and revascularization (Carotid Endarterectomy (CEA) versus Carotid Artery Stenting (CAS)) continue to be controversial. METHODS: The National Surgical Quality Improvement Program (NSQIP) targeted dataset for CEA and CAS was queried for symptomatic patients with &lt;50% stenosis of the ipsilateral carotid artery undergoing CEA and CAS between 2012-2019. Data analysis for continuous and categorical variables was carried out. RESULTS: A total of 363 symptomatic patients with &lt;50% stenosis of the ipsilateral carotid artery were identified of which 22 underwent CAS and 341 underwent CEA. Statistical analysis showed that patients undergoing CEA were more likely to be male as compared to those undergoing CAS (68% vs 54.5%, p &lt; 0.001). Additionally, patients in the CAS group were more likely to present with high-risk anatomy features compared to patients in the CEA group (31.8% vs 11.7%, p = 0.007) whereas patients undergoing CEA were more likely to have &lt;50% stenosis contralateral ICA stenosis when compared to patients undergoing CAS (65.1% vs 36.4%, p = 0.001). Furthermore, patients undergoing CAS were more likely to experience post procedural stroke at 30 days compared to those undergoing CEA (13.6% vs 3.8%, p = 0.03). Upon multivariable analysis, CEA was associated with lower odds of post procedural stroke as compared to CAS (OR = 0.17, 95% CI 0.033-0.82, p = 0.027). CONCLUSIONS: Carotid revascularization for SyNC is being performed despite current guidelines and CEA is associated with lower odds of post-procedural stroke compared to CAS.

Percutaneous Superficial Temporal Artery Access Facilitating Carotid Artery Stenting Performed From Distal Radial Artery.

The purpose of the study is to describe carotid artery stenting (CAS) via distal transradial access (dTRA) facilitated by additional superficial temporal artery (STA) access, in a patient with complex aortic arch vessel anatomy. A 72-year-old woman with a prior history of complex cervical surgery and radiotherapy due to laryngeal malignancy, presented with a symptomatic 90% stenosis of the left internal carotid artery (ICA). Due to high cervical lesion, the patient was rejected from carotid endarterectomy. Angiography demonstrated 90% stenosis of the left ICA and a type III aortic arch. After failure of left common carotid artery (CCA) cannulation with appropriate catheter support via dTRA and transfemoral approaches, CAS was attempted a second time. After percutaneous ultrasound guided access to right dTRA and left STA, a 0.035 inch guidewire introduced to the left CCA from the contralateral dTRA was snared and externalized via left STA to improve wire support for guiding advancement. Thereafter, the left ICA lesion was successfully stented with a 7×30 mm self-expanding stent via right dTRA. All vessels involved were patent at 6-month follow-up. The STA may be a promising adjunctive access site to increase transradial catheter support for CAS or neurointerventional procedures in the anterior circulation. Transradial cerebrovascular interventions have been gaining popularity, however, unstable catheter access to distal cerebrovascular structures limits its widespread use. Guidewire externalization technique via additional STA access may improve transradial catheter stabilty and increase procedural success with possibly low access stie complication rate.

Disturbed Ratios between Essential and Toxic Trace Elements as Potential Biomarkers of Acute Ischemic Stroke.

Cadmium (Cd) and lead (Pb) are known to be two of the metal contaminants that pose the greatest potential threat to human health. The purpose of this research study was to compare the levels of toxic metals (Cd, Pb) in patients with acute ischemic stroke (AIS), with a control group in Podlaskie Voivodeship, Poland. The study also aimed to assess the correlations between toxic metals and clinical data in AIS patients, and to assess the potential effect of smoking. The levels of mineral components in the collected blood samples were assessed by means of atomic absorption spectrometry (AAS). The Cd blood concentration was significantly higher in AIS patients as compared to the control group. We found that the molar ratios of Cd/Zn and Cd/Pb were significantly higher (p < 0.001; p < 0.001, respectively), when the molar ratios of Se/Pb, Se/Cd, and Cu/Cd were significantly lower (p = 0.01; p < 0.001; p < 0.001, respectively), in AIS patients as compared to control subjects. However, there were no considerable fluctuations in relation to the blood Pb concentration or molar ratios of Zn/Pb and Cu/Pb between our AIS patients and the control group. We also found that patients with internal carotid artery (ICA) atherosclerosis, particularly those with 20-50% ICA stenosis, had higher concentrations of Cd and Cd/Zn, but lower Cu/Cd and Se/Cd molar ratios. In the course of our analysis, we observed that current smokers among AIS patients had significantly higher blood-Cd concentrations, Cd/Zn and Cd/Pb molar ratios, and hemoglobin levels, but significantly lower HDL-C concentrations, Se/Cd, and Cu/Cd molar ratios. Our research has shown that the disruption of the metal balance plays a crucial role in the pathogenesis of AIS. Furthermore, our results broaden those of previous studies on the exposure to Cd and Pb as risk factors for AIS. Further investigations are necessary to examine the probable mechanisms of Cd and Pb in the onset of ischemic stroke. The Cd/Zn molar ratio may be a useful biomarker of atherosclerosis in AIS patients. An accurate assessment of changes in the molar ratios of essential and toxic trace elements could serve as a valuable indicator of the nutritional status and levels of oxidative stress in AIS patients. It is critical to investigate the potential role of exposure to metal mixtures in AIS, due to its public health implications.

Management of Cervical Internal Carotid Artery Stenosis or Occlusion in Tandem Lesion with Acute Ischemic Stroke: Which Is More Appropriate Percutaneous Transluminal Angioplasty or Stent?

Carotid artery stenting (CAS) is the established treatment strategy of the cervical internal carotid artery (cICA) stenosis, but its use for acute tandem lesions remains controversial. We investigated the clinical and procedural outcomes of management of cICA lesions and evaluated the risk factors for complications. Fifty patients who underwent acute mechanical thrombectomy for tandem lesion between January 2014 and June 2022 were included. Treatment of the cICA lesion was classified into the CAS group or the non-CAS group. The risk factors for postoperative ischemic events or symptomatic intracranial hemorrhage (sICH) were analyzed. The CAS group included 36 patients (72%) and the non-CAS group 14 (28%). Postoperative complications were observed in 9 patients (18%). Thromboembolic complications occurred in 4 patients (29%) of the non-CAS group but in 1 patient (3%) of the CAS group. Severe calcification of the cICA (P= 0.04), non-CAS (P= 0.018), and more than 60% residual stenosis (P= 0.016) were significant risk factors associated with thromboembolic complications. sICH occurred in 4 patients (11%) of the CAS group but in none of the non-CAS group. More than 80% stenosis improvement was significantly associated with sICH (P= 0.049). Twenty-nine patients (58%) had a good clinical outcome at 90 days after onset. Acute CAS is effective for the management for cICA tandem lesions during mechanical thrombectomy, but care not to overextend may be important to reduce the risk of sICH. Severe calcification of the cICA may increase the risk of postoperative thromboembolic complications using non-CAS treatment.

Case of Amaurosis Fugax in the Setting of a Persistent Primitive Hypoglossal Artery Requiring Carotid Endarterectomy with Regional Anesthesia.

BACKGROUND A persistent primitive hypoglossal artery (PPHA) is a rare congenital anomaly leading to persistent carotid-basilar anastomosis. This is a report of an 83-year-old man with a PPHA presenting with amaurosis fugax of the left eye requiring carotid endarterectomy under regional anesthesia. CASE REPORT An 83-year-old man presented with 2 weeks of intermittent self-resolving visual disturbances, followed by an episode of left eye amaurosis fugax. The patient had been referred to the hospital for further investigation of symptoms 1 day following the amaurosis fugax event. Carotid Doppler ultrasound demonstrated a greater than 90% stenosis of the left internal carotid artery. Computed tomography carotid and Circle of Willis angiography confirmed a mixed, ulcerated plaque and revealed a persistent left hypoglossal artery originating from the left internal carotid artery and continuing as the basilar artery. On day 3 of admission, left carotid endarterectomy was performed under conscious sedation and regional anesthesia to permit continuous monitoring of neurological status and avoid the need for intraoperative shunting. "Permissive hypertension" by targeting a systolic blood pressure of 190 to 200 mmHg was sought for the duration of clamp time. There was no deterioration of neurological function during clamping of the carotid vessels. The patient recovered well and was discharged 2 days after surgery, with no residual neurology. CONCLUSIONS This report has presented a rare case of PPHA to highlight awareness of this congenital vascular anomaly when undertaking carotid endarterectomy.

Severe blood pressure elevation following ephedrine administration during carotid endarterectomy under general anesthesia: A CARE-compliant case report.

During carotid endarterectomy (CEA) surgery, blood pressure management is particularly important to prevent cerebrovascular and cardiac complications. Ephedrine is a commonly used vasopressor, however, we report the case of a patient with unusually severe blood pressure elevation following intravenous ephedrine administration during CEA. A 72-year-old man diagnosed with right proximal internal carotid artery stenosis underwent CEA under general anesthesia. After declamping the common carotid artery, blood pressure rapidly increased by 125 mm Hg (from 90 to 215 mm Hg) after ephedrine (4 mg) was administered, but the heart rate was stable. There was an ordinal increase in blood pressure after the same small dose of ephedrine was administered at the early stage of the surgery. And the surgical approach was difficult because he had a high location of carotid bifurcation and a prominent mandibular angle. Because of the anatomical proximity of the cervical sympathetic trunk to the carotid bifurcation and the particularly complicated surgical process in the present case, we postulate the reason for this adverse reaction as transient sympathetic denervation supersensitivity. Perdipine (0.5 mg) was administered repeatedly to reduce blood pressure. After surgery, he was diagnosed with right hypoglossal nerve palsy, and no other abnormal signs were found. This case highlights the need for caution in the use of ephedrine, which is commonly used in CEA surgery, wherein blood pressure management is particularly important. Although it is a rare and unpredictable case, α-agonists are considered safer in situations where sympathetic supersensitivity is possible.

Abstract Number ‐ 244: Feasibility of Detecting Carotid Stenosis Microemboli Using Autonomous Robotic TCD at a Large Stroke Center

Introduction There is accumulating evidence that the presence of microembolic signals(MES) could be an independent risk factor and marker for future stroke or TIA. These signals detected by ultrasound represent small particles (platelets,plaque,fibrinogen) too small to cause a neurologic deficit, but can be a warning of a larger particle dislodging and blocking an intracranial artery. Transcranial doppler (TCD) studies are historically small. Few technicians have the specialized training to perform them and experienced users often have difficulty obtaining an adequate echogenic window. This study utilizes an autonomous robotic transcranial doppler (aTCD), driven by artificial intelligence to obtain and optimize the cerebral blood flow velocity signal. This tool makes data acquisition more efficient thus increasing analytical power through ease in obtaining larger sample sizes. This study focuses on the process of integrating such a tool. Complex vascular cases can utilize such a tool for patients on the borderline of needing a carotid stent or endarterectomy to help ensure the selection of optimal surgical candidates through better risk assessment methods. Methods NovaGuide™ 2 Intelligent Ultrasound (NovaSignal Corp. USA) was utilized to scan patients for microembolic signals that met our criteria. Our population consisted of male and female inpatients that were at least 18 years old at a single center with a CTA head and neck that revealed 50% or greater internal carotid artery stenosis for patients with neurological symptoms that could be associated with this artery. For patients that were asymptomatic with an incidental finding of internal carotid artery stenosis, we included 60% or greater stenosis. Stenosis was measured by NASCET criteria. If a patient received a stent or carotid endarterectomy during their hospitalization, a microembolic scan was obtained before and after their procedure if the initial scan was positive. Scans were performed for at least 30 minutes if the patient could tolerate this. Results Data collection is ongoing with a plan to scan 20 patients from July 2022 to October 2022, but the initial 12 patients revealed no MES which is contrary to the rate found in other studies. Potential confounders include antiplatelet and anticoagulation use as these were not delayed if clinically warranted. All cases were symptomatic and carotid stenosis ranged from 50% to 99%. A request for echo technician feedback is pending, but initial comments have revealed 30 minutes to be the maximum time feasible at our institution. Conclusions The aTCD has shown in a prospective study (NCT04604015) that data can be collected by non experts. Our study demonstrates that such a tool can be integrated into a large stroke center by echo technicians not formally trained in manual TCD. Utilization of technologies that allow for simplified data collection can help power larger TCD studies to explore its use as a risk utilization tool. This can help with selection of ideal surgical candidates for carotid stent and endarterectomy as an additional data point in their overall case. The significance of MES requires further investigation, but studies utilizing conventional TCD support MES being a risk factor for stroke and TIA.