Mechanisms of Early Recurrence in Intracranial Atherosclerotic Disease


The objective of this study is to determine the mechanisms of stroke in patients with Intracranial Atherosclerotic Disease (IAD) by specifically evaluating limitations of antegrade flow through the stenotic artery, distal tissue perfusion to the affected territory, and artery-to-artery embolism. The hypothesis is that non-invasive imaging biomarkers that stratify stroke risk and distinguish mechanisms of IADThis prospective multicenter study will enroll 175 patients with recently symptomatic (<7 days) high-grade IAD. Patients will be studied within 14 days of the index event (allowing appropriate time to arrange for diverse imaging modalities), with the following advanced neuroimaging techniques to elucidate mechanisms of recurrent ischemia: - Quantitative magnetic resonance imaging (QMRA) to assess volumetric flow rate through the stenotic artery. - Magnetic resonance perfusion weighted imaging (PWI-MRI) to determine distal tissue perfusion. - Vasomotor reactivity by transcranial Doppler using the breath-holding technique (BHI-TCD) to assess compensatory flow characteristics to the territory distal to the affected artery; - Transcranial Doppler with embolic signal monitoring to evaluate artery-to-artery embolism that reflects plaque instability. Patients will receive standardized medical management and its effectiveness on blood pressure, lipid, and glycemic control will be monitored. The primary outcome is recurrent stroke in the territory of the stenotic artery during a 1-year follow-up period; secondary outcomes are: a) new asymptomatic ischemic lesions on MRI in the distribution of the stenotic artery at 4-6 weeks, and b) transient ischemic attack (TIA) in the distribution of the stenotic artery during a 1-year follow-up period. Patients will be recruited at various sites that will be trained and certified on the imaging techniques employed. Raw imaging data will be interpreted centrally.

Study Start Date

January 2015

Estimated Completion Date

February 2019


No interventions cited


  • Cardiology: Atherosclerosis/Lipids
  • Internal Medicine: Atherosclerosis/Lipids,Neurology
  • Neurology: Stroke/Vascular
  • Family Medicine: Atherosclerosis/Lipids

MeSH Terms

  • Brain Diseases
  • Cerebrovascular Disorders
  • Vascular Diseases

Study ID

University of Miami -- 20140056



Trial ID


Study Type


Trial Phase


Enrollment Quota



University of Miami

Inclusion Criteria

    1. Stroke defined as symptoms lasting >24 hours and associated with imaging evidence of acute ischemia in the distribution of the stenotic vessel on CT or MRI. 2. Eligible TIA defined as transient neurological symptoms lasting <24 hours, need to be: 1. accompanied by DWI abnormalities in the distribution of the stenotic artery or 2. multiple (>2), stereotyped events associated with unequivocal ischemic symptoms (weakness, aphasia), and attributed to the symptomatic artery. 3. IAD should involve the intracranial carotid, middle cerebral, intracranial vertebral or basilar arteries. 4. Stenosis 70-99% quantified by digital subtraction angiography (DSA) or the combination of two non-invasive (CT angiography-CTA, MR angiography-MRA, transcranial Doppler-TCD) tests. DSA is not required but will be used if obtained as part of clinical care. The criteria for 70-99% are: 1. CTA or DSA: measured 70-99% stenosis by WASID criteria (percent stenosis = (1-[diameter stenosis/diameter normal]) x 100%. 2. MRA: presence of a flow gap. 3. TCD: mean flow velocity >100 cm/s for internal carotid and middle cerebral arteries >80 cm/s for vertebral and basilar arteries. 5. Age >30 those 30-49 years of age must also have the presence of established atherosclerotic disease in another vascular bed (coronary, extracranial carotid, peripheral) or the presence of 2 or more risk factors (hypertension, diabetes mellitus, hyperlipidemia, tobacco abuse within the last 2 years). 6. Enrollment within 7 days of symptom onset and completion of study imaging tests within 14 days of index event (stroke or TIA). 7. Provide informed consent for participation in the study.

Exclusion Criteria

    1. Other cause for stroke: atrial fibrillation, mitral stenosis, mechanical valve, intracardiac thrombus or vegetation, dilated cardiomyopathy or ejection fraction <30%, proximal extracranial carotid or vertebral stenosis >50%. 2. Contraindications to MRI, including MR-incompatible metallic implants, implanted electronic devices, other potentially mobile ferromagnetic material, pregnancy (women in fertile age should have a negative pregnancy test), lactation, morbid obesity, and severe claustrophobia. 3. Renal impairment defined as either a creatinine level >1.5 mg/dL or a glomerular filtration rate (GFR) <30 mL/min/1.73 m2. 4. Known allergy to gadolinium. 5. Unable to obtain informed consent by patient or legally authorized representative. 6. Severe behavioral or social problems that may interfere with the conduct of the study. 7. In the investigator's opinion, patient unlikely return for follow up visit and to complete the study.




30 Years and older

Accepts Healthy Volunteers


Study Locations and Contact Information (9)

Study Location Distance Name Phone Email
Columbia University Medical Center - New York, New York 44.8 miles Mitchell S Elkind MD 212-305-1710
SUNYUniversity at Buffalo - Buffalo, New York 309.9 miles Elad Levy MD 716-218-1010
Medical University of South Carolina - Charleston, South Carolina 691.2 miles Tanya Turan MD 843-792-9796
Rush University Medical Center - Chicago, Illinois 748.9 miles Sarah Y Song MD 312-563-2208
University of Alabama at Birmingham - Birmingham, Alabama 916.1 miles Mark Harrigan MD 205-934-3131
University of Florida - Gainesville, Florida 950.8 miles Anna Khanna MD 352-273-5550
University of Miami - Miami, Florida 1,141.0 miles Iszet C Bustillo MPH 305-243-8018
The University of Texas Southwestern Medical Center - Dallas, Texas 1,414.8 miles Mark Johnson MD 214-648-7811
UCLA - Los Angeles, California 2,499.3 miles David S Liebeskind MD 310-963-5539 provides clinical trial listings in an easy to view format. All clinical trial information is pulled directly from This website does not guarantee acceptance into any clinical trial, and is not responsible for adverse events that may be incurred from a clinical trial.