| - Background: Patients with transient ischaemic attacks or moderately disabling stroke that can be attributed to occlusion of the carotid artery have an average risk of recurrent ischaemic stroke of 9-18% per year if they have a compromised perfusion of the brain. To date no other treatment is found to be of proven value for these patients than antithrombotic agents and control of vascular risk factors. Based on our previous research we have developed a therapeutic paradigm that aims to increase perfusion of the hemisphere ipsilateral to the carotid artery occlusion. Cerebral perfusion, currently, can be reliably and non-invasively measured by means of arterial spin labelling perfusion magnetic resonance imaging (ASL-MRI) and additional valuable information on the haemodynamic status of the brain can be obtained with positron emission tomography (PET). - Hypothesis: Application of the therapeutic paradigm, consisting of endarterectomy of endovascular treatment of severely stenosed cerebropetal collateral pathways in combination with increasing blood pressure by tapering of antihypertensive medication will improve cerebral perfusion in patients with symptomatic carotid artery occlusion. - Methods: The haemodynamic status of the brain will be assessed in fifty patients with symptomatic carotid artery occlusion by means of ASL-MRI and PET at baseline and after 3 months. Subsequently patients will be randomised in two groups, stratified by the severity of haemodynamic compromise at baseline. One group will receive optimal antiplatelet therapy and control of vascular risk factors. The other group will in addition to antiplatelet therapy and control of vascular risk factors be treated according to the developed therapeutic paradigm. - Analysis: The primary outcome measures will be the changes in the haemodynamic status of the hemisphere on the side of the carotid artery occlusion, measured by the change in cerebral perfusion on ASL-MRI and PET and by change in oxygen extraction fraction on PET. The project will be a joint effort of the Departments of Neurology, Neurosurgery, Vascular Surgery, and Radiology of the University Medical Center Utrecht (UMCU) and the PET centre of the VU Medical Centre (VUMC), Amsterdam. Through our previous research we are in the unique position to receive referrals of patients from all over The Netherlands, which allows us to study this specific group of patients who are at high risk of recurrent ischaemic stroke. The results of the studies will have a direct impact on how patients with symptomatic carotid artery occlusion will be managed in the future and will guide us in the design of further studies aimed at improving treatment for patients with symptomatic carotid artery occlusion. |
