Individualized Physical Activity and Carotid Plaque Instability

Intraplaque hemorrhage (IPH) is one of the main features of the carotid plaque instability's and predictor of ischemic stroke. Benefits (on the basis on benefit/risk ratio) of the carotid endarterectomy remain unclear for stroke asymptomatic patients; thus, more and more patients with important stenosis (i.e. over 60%) detected are not operated. However, these patients need adapted therapeutic treatments to limit plaque instability and this should include physical activity (PA). Indeed, PA has been showed to decrease numerous inflammatory markers involved in atherosclerosis. It has also recently been reported on stroke asymptomatic patients that the prevalence of carotid IPH was decreased in those with higher level of PA. Magnetic Resonance Imaging (MRI) of the IPH has been shown to be the better non-invasive imaging technique to assess carotid plaque instability and in particular IPH. Here, the aim of this study is to assess the effect of an individualized home-based 6 months physical activity intervention on carotid IPH and other biomarkers of vulnerability for asymptomatic patients.

This study has been designed as a monocentric, longitudinal and interventional study. This study will involve one centre: Hopital Louis Pradel (HCL, Lyon). After inclusion tests, patients will be randomly included in the control group, or in the PA group. Patients of the PA group will have connected bracelets to measure daily count of steps. Twice a month, daily goals will be revaluated to increase or maintain the steps per day. The final goal is to reach 6 000 steps per day or increase by 30% the initial count of steps per day. Same tests will be done after 6 months of intervention for comparison.


Eligibility Criteria:
Inclusion Criteria:

* Patient with an carotid atheromatous plaque with ≥ 50% North American Symptomatic Carotid Endarterectomy Trial (NASCET) stenosis
* Patient from vascular surgery department of the Louis Pradel Hospital of the Hospices Civils de Lyon, but not operated
* Males and females aged over 18 years old
* No contra-indication to physical activity with index performance (PS) \< 2
* Available and voluntary to invest in the study throughout its duration (6 months)
* Able to understand, read and write French;
* a social security system or similar;
* Having dated and signed informed consent.

Exclusion Criteria:

* Transient ischemic attack (TIA) or ipsilateral cerebral infarction less than 6 months
* History of ipsilateral carotid surgery or cervical irradiation;
* Cancer, heart failure, seropositivity;
* Coronary risk;
* Renal failure (Cockcroft clearance of creatinine \< 30 milliliter/minute (mL/min);
* Contraindication and precautions for use related to Prohance: hypersensitivity to the active substance or to any of the constituents of Prohance, renal insufficiency with clearance \<30 ml / min / 1.73 m², probability of convulsions during the higher examination in patients with epilepsy or brain injury, pregnancy, breastfeeding;
* Contraindication to MRI: ferromagnetic material (including pacemaker, implantable defibrillators, cardiac valve prostheses, cochlear implants, neurostimulators, implanted automated injection equipment, intraocular metallic foreign bodies, neurosurgical and vascular clips);
* Carotid occlusion;
* ipsilateral intracranial stenosis;
* Risk of pregnancy or proven pregnancy on interrogation data. Breastfeeding;
* Patient under guardianship, under curatorship or safeguard of justice;
* inability to express consent;
* uncontrolled cardiological or neurological diseases;
* Impossibility of being followed for medical, social, geographical or psychological reasons throughout the duration of the study.