Endovascular Thrombectomy for a Progressive Stroke Patient With a High-Burden Carotid Free-Floating Thrombus.

Carotid free-floating thrombus (FFT) is a rare cause of acute ischemic events. The optimal management of carotid FFT remains unclear. The optimal and individualized management of carotid FFT should be determined based on the underlying etiology, clinical manifestation, and imaging characteristics. we reported a case with endovascular thrombectomy for a progressive stroke patient with a high-burden carotid free-floating thrombus. ANN NEUROL 2024;95:362-364.

Carotid free-floating thrombus in patients with acute ischaemic stroke and active cancer.

In patients with ischaemic stroke, a carotid free-floating thrombus (CFFT) raises diagnostic and therapeutic challenges. We describe two women, each taking tamoxifen for invasive non-metastatic breast cancer, who developed large-vessel occlusion ischaemic strokes. The first had a CFFT 24 hours after receiving intravenous thrombolysis and mechanical thrombectomy; the thrombus completely resolved after 1 week of therapeutic anticoagulation. The second had a tandem occlusion with a CFFT at admission; her neurological deficits rapidly improved after intravenous thrombolysis without needing a mechanical thrombectomy. However, subsequently, under therapeutic anticoagulation, distal migration of the CFFT caused a recurrent large vessel occlusion ischaemic stroke, requiring mechanical thrombectomy. The CTFF in both cases appeared to relate to a cancer-related prothrombotic state. Both received long-term oral anticoagulation and their tamoxifen was switched to anastrozole. At 3 months, both were functionally independent without recurrent vascular events.

Pulmonary venous thrombosis in a patient with COVID-19 infection.

OBJECTIVES: Infection with the SARS-COV2 virus (COVID-19) may be complicated by thrombotic diathesis. This complication often involves the pulmonary microcirculation. While macrovascular thrombotic complications of the lung may include pulmonary artery embolism, pulmonary artery thrombus in situ has also been hypothesized. Pulmonary vein thrombosis has not been described in this context. METHODS/RESULTS: Herein, we provide a case of an otherwise healthy male who developed an ischemic stroke with left internal carotid thrombus. Further imaging revealed pulmonary emboli with propagation through the pulmonary veins into the left atrium. This left atrial thrombus provides a source of atypical "paradoxic arterial embolism". CONCLUSIONS: Thrombotic outcomes in the setting of severe COVID 19 pneumonia may include macrovascular venous thromboembolism, microvascular pulmonary vascular thrombosis and arterial thromboembolism. Pulmonary vein, herein described, provides further mechanistic pathway for potential arterial embolic phenomenon.

External validation of prehospital stroke scales for emergent large vessel occlusion.

BACKGROUND: It is suggested that a prehospital scale should be utilized to identify patients with emergent large vessel occlusion (ELVO). We aimed to perform external validation of nine ELVO scales. METHODS: This single center retrospective observational study included patients with ischemic stroke visiting the emergency department (ED) within 6 h of symptom onset. Participants were excluded if individual items of the National Institute of Health Stroke Scale scores were not recorded or they did not receive brain computed tomography angiography or magnetic resonance imaging before intravenous thrombolysis or endovascular thrombectomy, and within 24 h of ED admission. The first definition of ELVO was emergent occlusion of the internal carotid artery (ICA) and middle cerebral artery segment 1 (M1). The second definition was emergent occlusion of ICA, M1, basilar artery, middle cerebral artery segment 2, anterior cerebral artery segment 1, and posterior cerebral artery segment 1. Area under the receiver operating characteristic curve (AUROC) was constructed to examine discrimination. The sensitivity, specificity, positive predictive value, and negative predictive value of the nine scales under the two ELVO definitions were calculated. RESULTS: A total of 1231 patients were included in the study. No significant differences were observed in the AUROC under the two ELVO definitions. However, sensitivity values of these scales were largely different, ranging from 44.56% to 93.68% under the first ELVO definition. The sensitivity values among scales were also different under the second ELVO definition. CONCLUSION: Stakeholders in the community should choose suitable scales according to their own system conditions.

Red and White Thrombus Characteristics in Patients Undergoing Carotid Endarterectomy.

OBJECTIVE: The study aimed to compare the characteristics of red and white thrombi in patients undergoing carotid endarterectomy. MATERIAL AND METHODS: The study was conducted in 81 patients with ischemic stroke who underwent carotid endarterectomy for carotid artery stenosis. Carotid plaques were graded by two pathologists. Thrombus materials were divided into two groups: white and red. The parameters of assessment were plaque rupture, lipid core, fibrous cap thickness, inflammation, intraplaque hemorrhage, calcification, necrotic core, and neovascularization. Normally distributed data were evaluated using Mann-Whitney U and Chi-squared tests. RESULTS: The ratio of white and red thrombus was 19.8% and 80.2%, respectively. Lipid core, plaque rupture, necrotic core, neovascularization, intraplaque hemorrhage, obstruction, and inflammation were observed more in red thrombus, which were statistically significant. Calcification and fibrous cap thickness were not statistically significant in the two groups. Moreover, intimal smooth muscle cells were present in all thrombus types. CONCLUSION: In our study, we found that red thrombi had more unstable characteristics than white thrombi. Thus, the risk for ischemic cerebrovascular events is more in red thrombi. However, this finding cannot be generalized due to the small number of patients in this study. Therefore, studies involving more patients are needed.

Neuroimaging in Ischemic Stroke Is Different Between Men and Women in the DEFUSE 3 Cohort.

Background and Purpose- Clinical deficits from ischemic stroke are more severe in women, but the pathophysiological basis of this sex difference is unknown. Sex differences in core and penumbral volumes and their relation to outcome were assessed in this substudy of the DEFUSE 3 clinical trial (Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke). Methods- DEFUSE 3 randomized patients to thrombectomy or medical management who presented 6 to 16 hours from last known well with proximal middle cerebral artery or internal carotid artery occlusion and had target core and perfusion mismatch volumes on computed tomography or magnetic resonance imaging. Using univariate and adjusted regression models, the effect of sex was assessed on prerandomization measures of core, perfusion, and mismatch volumes and hypoperfusion intensity ratio, and on core volume growth using 24-hour scans. Results- All patients were included in the analysis (n=182) with 90 men and 92 women. There was no sex difference in the site of baseline arterial occlusion. Adjusted by age, baseline National Institutes of Health Stroke Scale, baseline modified Rankin Scale score, time to randomization, and imaging modality, women had smaller core, hypoperfusion, and penumbral volumes than men. Median (interquartile range) volumes for core were 8.0 mL (1.9-18.4) in women versus 12.6 mL (2.7-29.6) in men, for Tmax>6 seconds 89.0 mL (63.8-131.7) versus 133.9 mL (87.0-175.4), and for mismatch 82.1mL (53.8-112.8) versus 108.2 (64.1-149.2). The hypoperfusion intensity ratio was lower in women, 0.31 (0.15-0.46) versus 0.39 (0.26-0.57), P=0.006, indicating better collateral circulation, which was consistent with the observed slower ischemic core growth than men within the medical group (P=0.003). Conclusions- In the large vessel ischemic stroke cohort selected for DEFUSE 3, women had imaging evidence of better collateral circulation, smaller baseline core volumes, and slower ischemic core growth. These observations suggest sex differences in hemodynamic and temporal features of anterior circulation large artery occlusions. Registration- URL: https://www.clinicaltrials.gov. Unique identifier: NCT02586415.

Posterior cerebral artery giant aneurysm associated with bilateral internal carotid artery occlusion in a Klippel-Trenaunay syndrome patient: a case report.

We experienced an extremely rare case of a giant P1-P2 partially thrombosed aneurysm associated with bilateral ICA occlusion in a Klippel-Trenaunay syndrome patient. In our experience, direct surgical clipping via a pterional approach is generally favored for aneurysms located in the junction of the P1-P2 segments, even if they are giant.

Inhibition of Factor XIa Reduces the Frequency of Cerebral Microembolic Signals Derived from Carotid Arterial Thrombosis in Rabbits.

Factor XI (FXI) is an integral component of the intrinsic pathway of the coagulation cascade and plays a critical role in thrombus formation. Because its role in the pathogenesis of cerebral microembolic signals (MES) is unclear, this study used a potent and selective small molecule inhibitor of FXIa, compound 1, to assess the effect of FXI blockade in our recently established preclinical model of cerebral MES induced by FeCl3 injury of the carotid artery in male New Zealand White rabbits. Ascending doses of compound 1 were evaluated simultaneously for both carotid arterial thrombosis by a Doppler flowmeter and MES in the middle cerebral artery by a transcranial Doppler. Plasma drug exposure and pharmacodynamic responses to compound 1 treatment were also assessed. The effective dose for 50% inhibition (ED50) of thrombus formation was 0.003 mg/kg/h compound 1, i.v. for the integrated blood flow, 0.004 mg/kg/h for reduction in thrombus weight, and 0.106 mg/kg/h for prevention of MES. The highest dose, 3 mg/kg/h compound 1, achieved complete inhibition in both thrombus formation and MES. In addition, we assessed the potential bleeding liability of compound 1 (5 mg/kg/h, i.v., >1250-fold ED50 levels in arterial thrombosis) in rabbits using a cuticle bleeding model, and observed about 2-fold (not statistically significant) prolongation in bleeding time. Our study demonstrates that compound 1 produced a robust and dose-dependent inhibition of both arterial thrombosis and MES, suggesting that FXIa blockade may represent a novel therapeutic strategy for the reduction in MES in patients at risk for ischemic stroke.

Stroke caused by an inflammatory thrombus: a case report.

BACKGROUND: Stroke is the leading cause of mortality and disability worldwide. Several definite risk factors have been identified for stroke, although infectious factors might also contribute to stroke episodes through increased susceptibility or direct induction. CASE PRESENTATION: A 46-year-old Chinese male initially presented with fever, headache, and impaired memory and developed disturbance of consciousness after admission. A clinical diagnosis of Staphylococcus aureus sepsis, massive cerebral infarction and haemorrhagic transformation (left internal carotid arterial system, inflammatory thrombus) were made based on brain radiography, blood culture and postoperative pathological examinations. These symptoms improved following antibiotic therapy with vancomycin and conventional treatments for stroke. CONCLUSION: For stroke patients without traditional cerebrovascular risk factors but with signs of infection, infectious causes should be considered.

Post Stroke Dysglycemia and Acute Infarct Volume Growth: A Study Using Continuous Glucose Monitoring.

BACKGROUND: The aim of the present study was to clarify the effect of glucose profiles after stroke, which was assessed by a continuous glucose monitoring (CGM) device. METHODS: Acute ischemic stroke patients within 24 h of onset were prospectively studied. CGM was performed for 72 h after admission. CGM parameters were evaluated as follows: (1) mean glucose level, (2) area under the curve (AUC) for glucose level >140 mg/dl and (3) SD of the glucose level. Infarct volume was measured at admission and 24 and 72 h after admission using diffusion-weighted imaging. CGM data and infarct volume growth were compared at 24 and 72 h. RESULTS: Seventy-eight patients were enrolled in the present study. Spearman's rank correlation coefficients showed that both the mean glucose level (r = 0.433, p < 0.001 for 24 h; r = 0.308, p = 0.006 for 72 h) and AUC >140 mg/dl (r = 0.417, p < 0.001 for 24 h; r = 0.277, p = 0.014 for 72 h) were significantly correlated with acute infarct volume growth. The SD of the glucose level was associated with infarct volume growth at 24 h (r = 0.303, p = 0.007), but not 72 h (r = 0.195, p = 0.088). CONCLUSION: Post-stroke hyperglycemia was associated with infarct volume growth during the acute phase of ischemic stroke.

[Free-floating thrombus in the internal carotid artery treated by anticoagulation and delayed carotid endarterectomy]. / Volne vlající trombus ve vnitrní karotide lécený antikoagulací a odlozenou chirurgickou endarterektomií vnitrní karotidy.

UNLABELLED: Free-floating thrombus in the internal carotid artery is a rare clinical finding. Only case reports and small cohorts of patients are described in the literature. The authors present a case report of a patient with ischemic stroke due to arterio-arterial embolisation from ulcerated internal carotid artery stenosis with a free-floating thrombus. Initially, the patient was treated with anticoagulants, resulting in total dissolution of the free-floating thrombus based on ultrasound documentation, without any further symptomatic embolisation. Endarterectomy was performed in the second step for the critical stenosis of the internal carotid artery. After this combined treatment, the patient showed no neurological deficit. Currently, the opinion on optimal therapy of the free-floating thrombus in the internal carotid artery still remains unclear. KEY WORDS: free-floating thrombus - anticoagulation internal carotid artery.

Early Loss of Immediate Reperfusion While Stent Retriever in Place Predicts Successful Final Reperfusion in Acute Ischemic Stroke Patients.

BACKGROUND AND PURPOSE: Degree of stent retriever engagement with target thrombi may be reflected by (1) immediate reperfusion (IR) on first deployment, indicating displacement of clot toward the vessel wall, and (2) by early loss of IR (ELOIR), indicating penetration of retriever struts through the thrombus. The relation of these early findings to final reperfusion and clinical outcomes has not been well delineated. METHODS: We investigated IR and ELOIR in patients undergoing stent retriever mechanical thrombectomy at an academic medical center between March 2012 and June 2014. RESULTS: Among 56 patients, IR itself was not associated with final successful reperfusion, which occurred in 66.7% of IR patients and 71.4% of non-IR patients (P=0.999). However, ELOIR was associated with a higher rate of final successful reperfusion (92% versus 44%; P=0.046). Patients with ELOIR had a higher nominal rate of final favorable outcome (42% versus 22%; P=0.64). CONCLUSIONS: ELOIR during the embedding period after deployment of stent retrievers is associated with successful final reperfusion, likely because of greater thrombus engagement with the stent retriever. ELOIR may be a useful finding to guide duration of embedding time in clinical practice and design of novel stent retrievers.

Intraluminal thrombus, intraplaque hemorrhage, plaque thickness, and current smoking optimally predict carotid stroke.

BACKGROUND AND PURPOSE: Intraplaque hemorrhage (IPH) is associated with acute and future stroke. IPH is also associated with lumen markers of stroke risk including stenosis, plaque thickness, and ulceration. Whether IPH adds further predictive value to these other variables is unknown. The purpose of this study was to determine whether IPH improves carotid-source stroke prediction. METHODS: In this retrospective cross-sectional study, patients undergoing stroke workup were imaged with MRI and IPH detection. Seven hundred twenty-six carotid-brain image pairs were analyzed after excluding vessels with noncarotid plaque stroke sources (420) and occlusions (7) or near-occlusions (3). Carotid imaging characteristics were recorded, including percent diameter and mm stenosis, plaque thickness, ulceration, intraluminal thrombus, and IPH. Clinical confounders were recorded, and a multivariable logistic regression model was fitted. Backward elimination was used to determine essential carotid-source stroke predictors with a threshold 2-sided P<0.10. Receiver operating characteristic analysis was performed to determine discriminatory value. RESULTS: Significant predictors of carotid-source stroke included intraluminal thrombus (odds ratio=103.6; P<0.001), IPH (odds ratio=25.2; P<0.001), current smoking (odds ratio=2.78; P=0.004), and thickness (odds ratio=1.24; P=0.020). The final model discriminatory value was excellent (area under the curve=0.862). This was significantly higher than the final model without IPH (area under the curve=0.814), or models using only stenosis as a continuous variable (area under the curve=0.770) or cutoffs of 50% and 70% (area under the curve=0.669), P<0.001. CONCLUSIONS: After excluding patients with noncarotid plaque stroke sources, optimal discrimination of carotid-source stroke was obtained with intraluminal thrombus, IPH, plaque thickness, and smoking history but not ulceration and stenosis.

Endovascular Treatment versus Sonothrombolysis for Acute Ischemic Stroke.

BACKGROUND: Currently, there are 2 strategies to increase the effect of systemic thrombolysis with alteplase (rtPA) in acute major stroke: endovascular treatment via stent retrieval and ultrasound enhancement (sonothrombolysis). This study compares these 2 approaches in patients with proximal intracranial occlusion of the anterior circulation. METHODS: Consecutive data on the treatment outcome of acute middle cerebral artery (M1) or carotid T occlusion were collected from 2 stroke centers: one center used rtPA plus endovascular stent retrieval as standard treatment and the other rtPA plus ultrasound (sonothrombolysis). The primary outcome was functional independence (modified Rankin scale (mRS) 0-2) after neurorehabilitation. RESULTS: A total of 132 patients were assessed (n = 73 endovascular, n = 59 sonothrombolysis). The rate of functional independence was higher for endovascular treatment (adjusted OR 3.89 (95% CI 1.36-12.58)). Additionally, ordinal mRS analysis favored the endovascular strategy (adjusted common OR 1.70 (95% CI 0.88-3.31)). Subgroup analysis showed that endovascular treatment was superior for carotid T occlusion (adjusted common OR 5.61 (95% CI 1.60-20.93)), but not for middle cerebral artery occlusion (adjusted common OR 1.07 (95% CI 0.47-2.43)). Symptomatic intracerebral hemorrhage occurred in 3 patients from the endovascular group. CONCLUSIONS: This observational study suggests that endovascular treatment of acute major anterior circulation stroke is superior to sonothrombolysis in terms of functional outcome. This benefit seems to pertain primarily to patients with carotid T occlusion, whereas patients with M1 occlusion seem to profit in a similar way from both methods. ( CLINICAL TRIAL REGISTRATION: URL: http://www.germanctr.de. Unique identifier: DRKS0000x200B;5305.).

Is Acute Carotid Artery Stent Thrombosis an Avoidable Complication?

The most serious complication of carotid artery stenting (CAS) is acute carotid artery stent thrombosis (ACAST). ACAST is a very rare complication, but it may lead to dramatic and catastrophic consequences. The most important cause is inadequate or ineffective antiaggregant therapy. It is very important to identify, before CAS, those patients who might be candidates for ACAST and to start antiplatelet therapy for them. Testing patients who are candidates for CAS for acetylsalicylic acid and clopidogrel resistance may prevent this complication.

Transcranial Doppler ultrasonography CO2 reactivity does not predict recurrent ischaemic stroke in patients with symptomatic carotid artery occlusion.

BACKGROUND: Patients with transient ischaemic attacks (TIAs) or minor disabling ischaemic stroke associated with an internal carotid artery (ICA) occlusion have a high risk of recurrent stroke in case of compromised cerebral blood flow. Recent studies showed that increased oxygen extraction fraction measured by positron emission tomography (PET) is still an independent predictor of subsequent stroke under current medical treatment, but PET facilities are not widely available. Transcranial Doppler (TCD) ultrasonography CO2 reactivity is a cheap and non-invasive alternative to measure haemodynamic compromise. The aim of our study was to investigate whether TCD CO2 reactivity is an independent predictor of recurrent ischaemic stroke in a large cohort of patients with symptomatic ICA occlusion in a time where rigorous control of vascular risk factors has been widely implemented in clinical practice. METHODS: Between July 1995 and December 2009, we included consecutive patients with TIAs or minor disabling ischaemic stroke (modified Rankin Scale ≤3) associated with ICA occlusion who were referred to the University Medical Centre Utrecht, The Netherlands. All patients were treated with antiplatelet therapy and received rigorous control of vascular risk factors, including statins, treatment for diabetes and hypertension and lifestyle advices. CO2 reactivity was measured with TCD within 3 months after presentation. We determined the predictive value of TCD CO2 reactivity for recurrent ischaemic stroke using Cox proportional hazard analysis. RESULTS: We included 201 patients with a median follow-up time of 7.1 years. Mean CO2 reactivity was 15% (±20 standard deviation). The annual rate for ipsilateral ischaemic stroke was 2.2% [95% confidence interval (CI) 1.4-3.2] and for any recurrent stroke 3.2% (95% CI 2.3-4.4). We did not find a significant relationship between CO2 reactivity and the risk of ipsilateral [hazard ratio (HR) for every increase in percentage point 1.01, 95% CI 0.99-1.02] or any recurrent ischaemic stroke (HR 1.01, 95% CI 0.998-1.02). Multivariable analysis showed a significant relationship with history of stroke (HR 4.0, 95% CI 1.8-9.0) for ipsilateral recurrent stroke, and age (HR for increase per year 1.05, 95% CI 1.01-1.09) and a history of stroke (HR 3.4, 95% CI 1.7-6.6) for any recurrent stroke. CONCLUSIONS: In patients with TIAs or non-disabling stroke associated with occlusion of the carotid artery, the long-term annual risk of stroke is generally low with careful control of vascular risk factors. Impaired CO2 reactivity measured within 3 months after presentation does not identify the subgroup of patients at high risk of recurrent ischaemic stroke.

Computed tomography angiography intraluminal filling defect is predictive of internal carotid artery free-floating thrombus.

INTRODUCTION: Filling defects at the internal carotid artery (ICA) origin in the work-up of stroke or transient ischemic attack may be an ulcerated plaque or free-floating thrombus (FFT). This may be challenging to distinguish, as they can appear morphologically similar. This is an important distinction as FFT can potentially embolize distally, and its management differs. We describe a series of patients with suspected FFT and evaluate its imaging appearance, clinical features, and evolution with therapy. METHODS: Between 2008 and 2013, we prospectively collected consecutive patients with proximal ICA filling defects in the axial plane surrounded by contrast on CT/MR angiography. We defined FFT as a filling defect that resolved on follow-up imaging. We assessed the cranial-caudal dimension of the filling defect and receiver operating characteristics to identify clinical and radiological variables that distinguished FFT from complex ulcerated plaque. RESULTS: Intraluminal filling defects were identified in 32 patients. Filling defects and resolved or decreased in 25 patients (78 %) and felt to be FFT; there was no change in 7 (22 %). Resolved defects and those that decreased in size extended more cranially than those that remained unchanged: 7.3 mm (4.2-15.9) versus 3.1 mm (2.7-3.7; p = 0.0038). Receiver operating characteristic analysis established a threshold of 3.8 mm (filling defect length), sensitivity of 88 %, specificity of 86 %, and area under the curve of 0.86 (p < 0.0001) for distinguishing FFT from plaque. CONCLUSION: Filling defects in the proximal ICA extending cranially >3.8 mm were more likely to be FFT than complex ulcerated plaque. Further studies evaluating filling defect length as a predictor for FFT are warranted.

Fragmental or massive embolization in cardiogenic stroke caused by nonvalvular atrial fibrillation.

BACKGROUND: After cardioembolic stroke (CES), left atrial thrombus (LAT) is detected by transesophageal echocardiography (TEE) in some cases but not in others. We propose that there are 2 types of embolization in CES: fragmental and massive embolization. METHODS: Consecutive patients with nonvalvular atrial fibrillation (AF) of acute CES or transient ischemic attack (TIA) were prospectively enrolled in the study between May 2009 and July 2011. TEE was performed within 7 days of admission. The patients were classified into 2 groups: those with occlusion of the main trunk (internal carotid artery, M1, and basilar artery; group M) and those with occlusion of other distal arteries (group D). Clinical features were compared between patients who did and did not have a thrombus on TEE. RESULTS: Of the 41 patients in the study, 21 were in group M and 20 were in group D. Age, sex, and treatment with tissue plasminogen activator did not differ significantly between the 2 groups. The rate of detection of LAT was significantly higher in group D (14% v 65%; P < .001). CONCLUSIONS: Patients with distal artery occlusion had a significantly higher rate of LAT compared to those with main trunk occlusion. Distal artery occlusion in CES therefore tends to result from fragmental embolization and is associated with a remnant LAT, with which there may be a concern of a risk of early recurrence.