Vascular Disorders of the Brain: CVA and TIA Definitions: 

Transient Ischemic Attack (TIA):  temporary disruption of blood flow within the brain, leading to neuronal dysfunction, causing temporary stroke-like symptoms.

Cerebrovascular Accidents (CVA also known as Stroke): disruption of blood flow within the brain leading to neuronal cell death due to deprivation of oxygen and nutrients, causing symptoms of stroke, and long-term damage.

Overview

• Vascular disorders involve interruption of blood supply to brain tissue.
• Causes include atherosclerosis, emboli, or vasospasm.
• Impaired blood flow leads to neuronal ischemia and damage.

Causes of Brain Vascular Events: 

1.  Atherosclerosis

• Plaque buildup in cerebral arteries diminishes blood flow.
• Can lead to partial or complete occlusion.

2.  Emboli

• Traveling blood clots or debris block arteries.
• Usually originate in other parts of the body (heart, carotids).

3.  Vasospasm

• Sudden constriction of blood vessels.
• Dysfunction of vessel walls, causing transient ischemia.

4.  Vessel Rupture

• Bleeding causes hemorrhagic stroke.
• Blood leakage increases ICP and adds toxicity to neurons.

Types of Cerebral Ischemia

1.  Global Cerebral Ischemia

• Entire brain’s blood supply is compromised.
• Causes:
  • Cardiac arrest.
  • Shock.
• Can lead to brain death if not promptly reversed.

2.  Focal Ischemia (Stroke)

• Affecting specific regions:
  • Causes neurological deficits depending on location.

Transient Ischemic Attack (TIA): The “Mini Stroke”

• Temporary lack of oxygen in a localized brain area.
• Usually due to:
  • Partial artery occlusion.
  • Small embolus.
  • Vasospasm.
• Symptoms:
  • Muscle weakness or paralysis.
  • Speech difficulties (aphasia).
  • Vision problems.
  • Dizziness, numbness.
  • Nausea and confusion.
• Usually full recovery within minutes to hours.

Significance

• Recurrent TIAs predict future full strokes.
• Signs include FAST:
  • Face drooping.
  • Arm weakness.
  • Speech difficulty.
  • Time to call 911.

Prognosis & Prevention

• Repeated TIAs are warning signs.
• Many first-time strokes occur after a TIA.
• In the US:
  • One stroke every 45 seconds.
  • 1 in 15 deaths attributed to stroke.
• Early recognition and treatment save lives.

CVA Diagnosis and Imaging

• Crucial for confirming stroke type and extent.
• Imaging options:
  • CT scan: rapid detection of bleeding or infarct.
  • MRI: detailed visualization, especially of ischemia.
  • Angiography: blood vessel blockage.
  • Ultrasound: carotid artery flow.
• Assessment:
  • Identify location and size of the lesion.
  • Detect hemorrhages and ischemic areas.

CVA Treatment Strategies

• Clot removal and clot-busting:
  • Thrombolytic medications (e.g., tissue plasminogen activator, tPA).
  • Mechanical thrombectomy for large clots.
• Blood flow restoration:
  • Endarterectomy for carotid plaques.
  • Balloon angioplasty or stenting.
• ICP management:
  • Monitor intracranial pressure.
  • Use diuretics, hyperventilation, or surgical decompression.
• Relieve bleeding:
  • Surgical evacuation in hemorrhagic stroke.
• Supportive care:
  • Oxygen.
  • Blood pressure control.
  • Rehabilitation therapies:
    • Physical, occupational, and speech therapy.

Long-term Management

• Prevent recurrence:
  • Medications and lifestyle modifications.
  • Control of hypertension, diabetes, and hyperlipidemia.

Signs of Stroke & Neurological deficits

Assessment Tools

NIH Stroke Scale (NIHSS)

• Purpose: Quantifies stroke severity.
• Parameters:
  • Level of consciousness.
  • Gaze and visual fields.
  • Facial palsy.
  • Motor strength (arms and legs).
  • Sensory deficits.
  • Language and speech.
  • Extinction/inattention.
• Scores:
  • 0–4: Minor stroke.
  • 5–15: Moderate stroke.
  • 16–20: Severe stroke.
  • 21–42: Very severe (poor prognosis).
• Note: The scale guides clinical decision-making but does not need to be memorized.

FAST (Face, Arms, Speech, Time)

• A quick tool for recognizing stroke signs.
• Face drooping.
• Arm weakness.
• Speech difficulty.
• Time to call 911.

Management & Response

• Immediate action:
  • Recognize signs (FAST).
  • Call 911.
  • Get the person to the hospital.
• Preventive measures:
  • Control blood pressure.
  • Manage atherosclerosis.
  • Lifestyle: quit smoking, healthy diet, exercise.

Summary

• Cerebral blood flow interruption can cause temporary or permanent brain damage.
• Early detection of TIA and stroke symptoms is critical.
• Early intervention with imaging and clot-busting drugs improves outcomes.
• Long-term care involves supporting recovery and preventing recurrence via medication and lifestyle change.