Project description:A microarray analysis of advanced human atherosclerotic carotid artery plaques (equal or over 70% stenosis, NASCET criteria) from radiologically confirmed ipsilateral stroke patients (stroke-susceptible plaques, n=12) compared with carotid plaques collected from clinically asymptomatic patients with clear brain imaging (asymptomatic plaques, n=9) with equivalent conventional risk factors and severity of carotid stenosis.
Project description:We present a radiology-pathology case series of 3 patients with coronavirus disease 2019 (COVID-19) with acute ischemic stroke due to fulminant carotid thrombosis overlying mild atherosclerotic plaque and propose a novel stroke mechanism: COVID-associated carotid atherothrombosis.
Project description:BackgroundPopulation-based studies have estimated that about 15% of ischemic strokes are caused by large-vessel cerebrovascular disease. We determined the types of large-vessel atherosclerosis responsible for ischemic strokes in a population-based stroke study.MethodsPatients with first-ever or recurrent ischemic stroke in the Greater Cincinnati area were identified during 2005 at all local hospitals. Study physicians assigned ischemic stroke subtypes. Overall event rates and incidence rates for first-ever events were calculated, and age-, race- and sex-adjusted to the 2000 US population.ResultsThere were 2,204 ischemic strokes, including 365 strokes of large-vessel subtype (16.6% of all ischemic strokes). Extracranial internal carotid artery (ICA) stenosis was associated with 8.0% of all ischemic strokes, while extracranial ICA occlusion and intracranial atherosclerosis were each associated with 3.5% of strokes. The annual rate of first-ever and recurrent stroke attributed to extracranial ICA was 13.4 (11.4-15.4) per 100,000 persons. We conservatively estimate that about 41,000 strokes may be attributed to extracranial ICA stenosis annually in the United States.ConclusionsLarge-vessel atherosclerosis is an important cause of stroke, with extracranial ICA stenosis being significantly more common than extracranial ICA occlusion or intracranial atherosclerotic disease.
Project description:Background and purposeIn 2006, the American Heart Association recommended that carotid revascularization generally occurs within 2 weeks of stroke based on data from 2 trials of carotid endarterectomy (CEA). We aimed to determine whether the time between stroke and CEA or carotid artery stenting (CAS) has decreased and whether the proportion of procedures occurring within 14 days has increased.MethodsUsing validated International Classification of Diseases, Ninth Revision, Clinical Modification codes and administrative claims data from nonfederal hospitals in CA, FL, and NY, we identified patients with ischemic stroke who underwent CEA or CAS within 90 days of an ischemic stroke from 2005 to 2013. Our outcomes were the number of days between stroke and CEA/CAS and the proportion of patients undergoing CEA/CAS within the recommended 14-day period. We assessed temporal trends using nonparametric correlation, the χ2 test for trend, and logistic regression.ResultsWe identified 16 298 patients with ischemic stroke who underwent CEA/CAS within 90 days. The time from stroke to CEA/CAS decreased from 25 days (interquartile range, 5-48 days) in 2005 to 6 days (interquartile range, 3-17 days) in 2013 (P<0.001). The proportion of patients who underwent CEA/CAS within 14 days of stroke increased from 40% (95% confidence interval, 37%-43%) in 2005 to 73% (95% confidence interval, 71%-76%) in 2013 (P<0.001). These temporal trends remained significant after adjustment for patient demographics and comorbidities.ConclusionsSince 2005, revascularization for symptomatic carotid disease has been occurring progressively sooner after ischemic stroke.
Project description:ObjectiveTo decrease the procedural risk of carotid revascularisation it is crucial to understand the mechanisms of procedural stroke. This study analysed the features of procedural strokes associated with carotid artery stenting (CAS) and carotid endarterectomy (CEA) within the International Carotid Stenting Study (ICSS) to identify the underlying pathophysiological mechanism.Materials and methodsPatients with recently symptomatic carotid stenosis (1,713) were randomly allocated to CAS or CEA. Procedural strokes were classified by type (ischaemic or haemorrhagic), time of onset (intraprocedural or after the procedure), side (ipsilateral or contralateral), severity (disabling or non-disabling), and patency of the treated artery. Only patients in whom the allocated treatment was initiated were included. The most likely pathophysiological mechanism was determined using the following classification system: (1) carotid-embolic, (2) haemodynamic, (3) thrombosis or occlusion of the revascularised carotid artery, (4) hyperperfusion, (5) cardio-embolic, (6) multiple, and (7) undetermined.ResultsProcedural stroke occurred within 30 days of revascularisation in 85 patients (CAS 58 out of 791 and CEA 27 out of 819). Strokes were predominately ischaemic (77; 56 CAS and 21 CEA), after the procedure (57; 37 CAS and 20 CEA), ipsilateral to the treated artery (77; 52 CAS and 25 CEA), and non-disabling (47; 36 CAS and 11 CEA). Mechanisms of stroke were carotid-embolic (14; 10 CAS and 4 CEA), haemodynamic (20; 15 CAS and 5 CEA), thrombosis or occlusion of the carotid artery (15; 11 CAS and 4 CEA), hyperperfusion (9; 3 CAS and 6 CEA), cardio-embolic (5; 2 CAS and 3 CEA) and multiple causes (3; 3 CAS). In 19 patients (14 CAS and 5 CEA) the cause of stroke remained undetermined.ConclusionAlthough the mechanism of procedural stroke in both CAS and CEA is diverse, haemodynamic disturbance is an important mechanism. Careful attention to blood pressure control could lower the incidence of procedural stroke.
Project description:BackgroundStroke occurs more commonly after carotid artery stenting than after carotid endarterectomy. Details regarding stroke type, severity, and characteristics have not been reported previously. We describe the strokes that have occurred in the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST).Methods and resultsCREST is a randomized, open-allocation, controlled trial with blinded end-point adjudication. Stroke was a component of the primary composite outcome. Patients who received their assigned treatment within 30 days of randomization were included. Stroke was adjudicated by a panel of board-certified vascular neurologists with secondary central review of clinically obtained brain images. Stroke type, laterality, timing, and outcome were reported. A periprocedural stroke occurred among 81 of the 2502 patients randomized and among 69 of the 2272 in the present analysis. Strokes were predominantly minor (81%, n=56), ischemic (90%, n=62), in the anterior circulation (94%, n=65), and ipsilateral to the treated artery (88%, n=61). There were 7 hemorrhages, which occurred 3 to 21 days after the procedure, and 5 were fatal. Major stroke occurred in 13 (0.6%) of the 2272 patients. The estimated 4-year mortality after stroke was 21.1% compared with 11.6% for those without stroke. The adjusted risk of death at 4 years was higher after periprocedural stroke (hazard ratio, 2.78; 95% confidence interval, 1.63-4.76).ConclusionsStroke, particularly severe stroke, was uncommon after carotid intervention in CREST, but stroke was associated with significant morbidity and was independently associated with a nearly 3-fold increased future mortality. The delayed timing of major and hemorrhagic stroke after revascularization suggests that these strokes may be preventable.
Project description:Atrial fibrillation (AF) is a major risk factor for cardioembolic stroke. Anticoagulant drugs are effective in preventing AF-related stroke. However, the high frequency of anticoagulant-associated major bleeding is a major concern particularly when antiplatelet treatment is simultaneously administered. Here, microarray analysis in peripheral blood cells in eight patients with AF and stroke and eight AF subjects without stroke identified a stroke related gene expression pattern. HSPA1B, which encodes for heat-shock protein 70 kDa (Hsp70), was the most differentially expressed gene. This gene was downregulated in stroke subjects, a finding confirmed further in an independent AF cohort of 200 individuals. Hsp70 knock-out (KO) mice subjected to different thrombotic challenges developed thrombosis significantly earlier than their wild-type (WT) counterparts. In WT mice, Hsp70 inducers (TRC051384, or tubastatin A) delayed thrombus formation. Remarkably, Hsp70 inducers did not increase the bleeding risk even when aspirin was concomitantly administered. Hsp70 induction was associated with an increased vascular thrombomodulin expression, higher circulating levels of activated protein C (APC) upon thrombotic stimulus and increased protection against endothelial apoptosis. Thus, Hsp70 induction is a novel approach to delay thrombus formation with minimal bleeding risk, being especially promising in situations where there is a major bleeding hazard. Microarray analysis in peripheral blood cells includes eight patients with AF and stroke and eight AF subjects without stroke
Project description:Extracranial carotidartery stenosis is an important cause of stroke that often needs treatment with carotid revascularization. To prevent stroke recurrence, carotid endarterectomy has been well-established for many years in treating symptomatic high- and moderate-grade stenosis. Carotid stenting is an appealing, less invasive alternative to carotid endarterectomy, and several recent trials have compared the efficacy of the 2 procedures in patients with carotid stenosis. Carotid artery stenting has emerged as an important mode of therapy for high-risk patients with symtomatic high-grade stenosis. This review focuses on the current data available that will enable the clinician to decide optimal treatment strategies for patients with carotid stenosis.