Track topics on Twitter Track topics that are important to you
As with coronary artery stenting, activation and embolisation of platelets occurs with carotid artery stenting (CAS). Based on promising data on the use of clopidogrel plus aspirin in coronary stenting this dual antiplatelet regimen has been introduced as adjunctive treatment during CAS. There is as yet, however, no randomized controlled trial which compared different loading doses of clopidogrel during CAS. Taking into account that a wide interindividual variability in the response to a loading of clopidogrel exists, this study is intended to establish the optimal loading dose of clopidogrel. Therefore platelet function testing and a 1-hour of postprocedural TCD (transcranial doppler) monitoring will be performed.
Objective: Firstly, to investigate whether the absolute magnitude of Platelet Inhibition inversely correlates with the number of TCD-detected microemboli during and after CAS in patients who are being pre-treated with either a 300 mg or a 600 mg loading dose of clopidogrel. Secondly, if there is any impact on early neurological outcome determined by the loading dose of clopidogrel.
Carotid angioplasty with stent placement (CAS) has become a well-accepted treatment option for carotid artery stenosis. In combination with experience in CAS procedures and the introduction of protection devices and low-profile systems, the periprocedural risk of thromboembolic complications are comparable to that of standard surgical carotid endarterectomy (CEA) In our centre, all patients with severe asymptomatic carotid artery disease ( luminal diameter reduction of more than 80%, according to NASCET criteria) scheduled for cardiac surgery are eligible for CAS.
As with coronary artery stenting , activation and embolisation of platelets occurs with CAS. Based on promising data on the use of clopidogrel plus aspirin in coronary stenting, this dual antiplatelet regimen has been introduced in CAS. Specifically, an antiplatelet regimen with aspirin(300mg) and a 300 mg loading dose of clopidogrel at least 24 hours before carotid angioplasty has currently been the treatment of choice in carotid angioplasty with stent placement.
However, several studies have reported a wide interindividual variability in the response to a 300 mg loading of clopidogrel with a subsequent substantial proportion of patients not receiving the optimal benefit from it. Therefore, it has been suggested that a 600 mg loading dose will result in a faster onset, a higher responsiveness and a higher magnitude of platelet inhibition without any increase in bleeding complications. For these reasons, the interventional cardiology has already adopted the 600 mg loading dose regimen as standard of care during percutaneous coronary interventions. There is as yet, however, no randomized controlled trial which compared different loading doses of clopidogrel during CAS.
Using transcranial Doppler (TCD) monitoring of the middle cerebral artery during CAS, it is possible to register the number of TCD-detected microembolic signals during and after CAS. This monitoring enables the operator to diminish the risk of stroke during CAS. However, a significant number of patients develop an ischemic stroke in the hours following CAS after a symptom-free interval As published by van der Schaaf et al., in TCD monitoring after CEA, one hour of monitoring appeared to be effective to select those patients in whom the number of microemboli did not spontaneously decrease. More important, postoperative TCD monitoring was able to detect those patients who were at risk for new adverse cerebral events after the operation. Other studies demonstrate the potential application of ultrasonic emboli detection to examine the efficacy of new platelet agents in relatively small number of patients.
It remains to be established whether a higher magnitude of platelet inhibition before CAS has an additional protective effect by decreasing the microembolic load measured on TCD after the procedure. Moreover, such a TCD-monitoring post-CAS has not been performed systematically in the past and thus could reveal valuable information helpful to the understanding of post procedural cerebral complications and risk stratification.
Primary Purpose: Treatment
Published on BioPortfolio: 2014-08-27T03:12:49-0400
Patients with symptomatic or asymptomatic carotid stenosis in whom carotid artery stenting is planned are randomised between antiplatelet therapy with ticagrelor plus aspirin or clopidogre...
The purpose of this study is to determine the accuracy of a new non-invasive device, the Carotid Stenotic Scan (CSS), to check for stenosis of the internal carotid artery (ICA) as compared...
To evaluate the safety and efficacy of the Bard ViVEXX Carotid Stent and Emboshield BareWire Rapid Exchange Embolic Protection System in the treatment of extracranial carotid artery stenos...
The aim of the study is to confirm, whether the MER® stent can be used, without limitations, for the endovascular carotid stenosis treatment in daily clinical practice. Eligible patients ...
Carotid revascularization for primary prevention of stroke (CREST-2) is two independent multicenter, randomized controlled trials of carotid revascularization and intensive medical managem...
Carotid artery stenosis influences CT perfusion (CTP) studies, sometimes manifesting as a false ischaemic penumbra (FIP). This study aims to estimate the incidence of FIP in patients with carotid arte...
We hypothesized the inflammatory markers (IM) could be independent predictors of carotid stenosis progression (CSP) after carotid artery stenting (CAS).
Increased platelet count and reticulated platelets in recently symptomatic versus asymptomatic carotid artery stenosis and in cerebral microembolic signal-negative patient subgroups: results from the HaEmostasis In carotid STenosis (HEIST) study.
The pathophysiological mechanisms responsible for the disparity in stroke risk between asymptomatic and symptomatic carotid stenosis patients are not fully understood. The functionally important retic...
Surgical treatment of radio-induced carotid stenosis (RICS) is challenging and burdened by an elevated risk of local complications. Carotid artery stenting (CAS) may be a suitable alternative. The bes...
The purpose of this study was to determine the incidences and rates of progression of varying degrees of carotid stenosis that do not require intervention according to the Asymptomatic Carotid Atheros...
Blood clot formation in any part of the CAROTID ARTERIES. This may produce CAROTID STENOSIS or occlusion of the vessel, leading to TRANSIENT ISCHEMIC ATTACK; CEREBRAL INFARCTION; or AMAUROSIS FUGAX.
Narrowing or stricture of any part of the CAROTID ARTERIES, most often due to atherosclerotic plaque formation. Ulcerations may form in atherosclerotic plaques and induce THROMBUS formation. Platelet or cholesterol emboli may arise from stenotic carotid lesions and induce a TRANSIENT ISCHEMIC ATTACK; CEREBROVASCULAR ACCIDENT; or temporary blindness (AMAUROSIS FUGAX). (From Adams et al., Principles of Neurology, 6th ed, pp822-3)
Transient complete or partial monocular blindness due to retinal ischemia. This may be caused by emboli from the CAROTID ARTERY (usually in association with CAROTID STENOSIS) and other locations that enter the central RETINAL ARTERY. (From Adams et al., Principles of Neurology, 6th ed, p245)
Damages to the CAROTID ARTERIES caused either by blunt force or penetrating trauma, such as CRANIOCEREBRAL TRAUMA; THORACIC INJURIES; and NECK INJURIES. Damaged carotid arteries can lead to CAROTID ARTERY THROMBOSIS; CAROTID-CAVERNOUS SINUS FISTULA; pseudoaneurysm formation; and INTERNAL CAROTID ARTERY DISSECTION. (From Am J Forensic Med Pathol 1997, 18:251; J Trauma 1994, 37:473)
Pathological conditions involving the CAROTID ARTERIES, including the common, internal, and external carotid arteries. ATHEROSCLEROSIS and TRAUMA are relatively frequent causes of carotid artery pathology.
Blood is a specialized bodily fluid that delivers necessary substances to the body's cells (in animals) – such as nutrients and oxygen – and transports waste products away from those same cells. In vertebrates, it is composed of blo...