Surgical Indirect Revascularization For Symptomatic Intracranial Arterial Stenosis

Inclusion Criteria

• TIA or non-severe stroke within 30 days of enrollment attributed to 70% to 99% stenosis* of a major intracranial artery (carotid artery or MCA)

*May be diagnosed by TCD, MRA, or CTA to qualify, but must be confirmed by catheter angiography as per usual clinical practice.

• Modified Rankin scale score of ≤3
• Target area of stenosis in an intracranial artery that has a normal diameter of 2.00 mm to 4.50 mm
• Target area of stenosis is ≤14 mm in length
• Age ≥30 years and ≤80 years
• Patients 30 to 49 years of age are required to meet at least 1 additional criteria (i-vi) provided below to qualify for the study. This additional requirement is to increase the likelihood that the symptomatic intracranial stenosis in patients 30 to 49 years is atherosclerotic: i. Insulin-dependent diabetes for at least 15 years ii. At least 2 of the following atherosclerotic risk factors: hypertension (BP ≥ 140/90 mm Hg or on antihypertensive therapy); dyslipidemia (LDL ≥130 mg/dL or HDL ≤40 mg/dL or fasting triglycerides ≥150 mg/dL or on lipid lowering therapy); smoking; non-insulin-dependent diabetes or insulin-dependent diabetes of 5 cm) to be at risk of hemorrhagic conversion during or after surgery
• Any hemorrhagic infarct within 14 days before enrollment
• Any hemorrhagic infarct within 15 to 30 days that is associated with mass effect
• Any history of a primary intracerebral (parenchymal) hemorrhage
• Any other intracranial hemorrhage (subarachnoid, subdural, or epidural) within 30 days
• Any untreated chronic subdural hematoma >5 mm in thickness
• Intracranial arterial stenosis related to arterial dissection, Moya-Moya disease; any known vasculitic disease; herpes zoster, varicella zoster or other viral vasculopathy; neurosyphilis; any other intracranial infection; any intracranial stenosis associated with cerebrospinal fluid pleocytosis; radiation-induced vasculopathy; fibromuscular dysplasia; sickle cell disease; neurofibromatosis; benign angiopathy of central nervous system; postpartum angiopathy; suspected vasospastic process, and suspected recanalized embolus
• Presence of any of the following unequivocal cardiac sources of embolism: chronic or paroxysmal atrial fibrillation, mitral stenosis, mechanical valve, endocarditis, intracardiac clot or vegetation, myocardial infarction within 3 months, dilated cardiomyopathy, left atrial spontaneous echo contrast, ejection fraction 1.5, clotting factor abnormality that increases the risk of bleeding, current alcohol or substance abuse, uncontrolled severe hypertension (systolic BP>180 mm Hg or diastolic BP>115 mm Hg), severe liver impairment (AST or ALT > 3 times normal, cirrhosis), creatinine > 3.0 (unless on dialysis)
• Major surgery (including open femoral, aortic, or carotid surgery) within previous 30 days or planned in the next 90 days after enrollment
• Indication for warfarin or heparin beyond enrollment (NOTE: Exceptions allowed for use of subcutaneous heparin for deep venous thrombosis prophylaxis while hospitalized)
• Severe neurologic deficit that renders the patient incapable of living independently
• Dementia or psychiatric problem that prevents the patient from following an outpatient program reliably
• Comorbid conditions that may limit survival to < 3 years
• Females who are pregnant or of childbearing potential and unwilling to use contraception for the duration of this study
• Enrollment in another study that would conflict with the current study

Surgical Specific Exclusion Criteria:

In addition to those enumerated above, given the surgical nature of the intervention for patients failing best medical therapy, the following are additional exclusion criteria:

• Use of clopidogrel or extended release dipyridamole within 7 days of the date of surgery. This exclusion is based on the elevated risk of hemorrhagic complications for intracranial surgery using those agents according to the current AHA/ACC Guidelines (Fleis