PM&R News   •   February 2021

Anatomy/Etiology:

• • Disruption of circulatory system:
    • Large artery disease, carotid stenosis, small vessel disease (lipohyalinosis), cryptogenic (unknown origin), embolus, atherosclerosis, inflammation, amyloid (protein associated with certain diseases) deposition, arterial dissection, developmental malformation, aneurysmal dilation, or thrombosis.
    • Secondary to: atrial fibrillation, decreased perfusion pressure, or increased blood viscosity.
  • That leads to ischemia in any of the following: brain, spinal cord, or retina.

Pathophysiology

• • TIA definition (UTD): “Transient episode of neurologic dysfunction caused by focal brain, spinal cord, or retinal ischemia, without acute infarction” or injury to tissues.
    • Highest risk of CVA in the first 2 days.
    • Transient disruption of blood flow to the brain.
  • Distinguished from minor stroke by lack of persistence of non-disabling symptoms

Epidemiology

• • M > F
  • S.: estimated 1.1/1,000
  • Europe were 0.52-2.37 (M) and 0.05-1.14 (F): 55-64 y/o; 0.94-3.39 & 0.71-1.47: 65-74 y/o, 3.04-7.20 & 2.18-6.06: 75-84 y/o.
    • similar in the United States; lower in Japan
  • Risk factors
    • Increasing age, prior CVA (stroke) hx, diabetes, hypertension , smoking, obesity, alcoholism, unhealthy diet, psychosocial stress, and lack of physical activity.

Presentation/ Clinical Manifestations

• • Symptoms
    • Transient: typically, lasts less than 1 hour
    • Typically characterized by negative symptoms (lack of vision, hearing, sensation or loss of function)
    • Presence of cortical symptoms (ie: language disturbance, visual field loss, etc…)
    • Identify: onset, duration, timing, complete neurological symptoms, their associated symptoms, and any aggravating or relieving factors.
  • Physical Exam findings
    • neurological deficits (Most Common)
    • speech deficits (Most Common)
    • CN examination
    • Motor testing (weakness, clonus, reflexes)
    • Cardiac exam & carotid auscultation: looking for carotid bruit (indicative of stenosis)
    • Fundoscopic examination (DM/HTN changes or Hollenhurst plaque (cholesterol embolus; indicative of internal carotid artery disease)

Differential Diagnoses:

• • Seizure, migraine aura, syncope, transient global ischemia, CNS demyelinating disease, peripheral vestibulopathy, metabolic disorder

Diagnosis

• • Hx
    • Symptoms can be focalized to a single vascular region in the brain
  • Neuroimaging
    • Goals:
      • locate hypoperfusion, plausible source, and/or infraction area
      • exclude other causative diagnoses
      • Establish the underlying vascular issue (aids in tx)
      • Establish prognosis
    • CT or MRI: Indicated in ALL suspected pt.’s within 24 hrs
      • MRI with diffusion-weighted imaging > Sensitivity for small infarcts
        • If unavailable, recommend CT angiogram
      • Assess cervicocephalic vasculature for atherosclerotic lesions
        • carotid US/transcranial Doppler US, magnetic resonance angiography (MRA), or CT angiography.
      • If suspected carotid source, imaging should be completed within 1 week
        • ECG, Echocardiogram/TEE
      • If suspected cortical infarct without embolus: Holter monitor
    • Recommended Labs: (CBC), PT/INR, CMP, FBS, lipid panel, urine drug screen, and ESR
      • Aids in ruling out metabolic and hematologic sources.
    • Predicting future risk of TIA or CVA: ABCD² score (Calculator)
      • Stroke centers typically admit with a score of­ >4

Treatment: may reduce risk of recurrent CVAs by ~80%

• • UK’s EXPRESS study found reduction of CVA risk by 80% in those treated < 1 day
    • Incorporated the following immediately (individualized per patient): “antiplatelet or anticoagulant therapy, statin therapy, antihypertensive medication, and carotid endarterectomy.”
  • Tx by etiology:
    • Large artery disease: revascularization (symptomatic ICA stenosis) or pharmacologic therapy (antiplatelets, antihypertensives, statins)
    • Small vessel disease or cryptogenic: pharmacologic therapy (See above^)
    • A-fib: oral anticoagulation (Warfarin or direct oral anticoagulant)
    • Symptomatic CAD (carotid artery disease): carotid endarterectomy w/in 2 weeks
      • 50-99% symptomatic who have > 5 yr life expectancy

Patient Education

• • 20% of patients will have a CVA within 3 months (50% within first 2 days)
  • Dutch TIA trial: 60% mortality within 10 years after TIA (event-free survival 48%).
  • Reduction of CVA risk by 80-90% when adhering to the following: “diet, exercise, antiplatelet, statin and antihypertensive therapy”
    • Other lifestyle changes: smoking cessation, losing weight, reduce sodium

intake, alcohol reduction

• Teach your patient signs of stroke/TIA: FAST
  • Face is uneven
  • Arm is weak
  • Speech is strange
  • Time to call an ambulance

References:

1. https://www.uptodate.com/contents/initial-evaluation-and-management-of-transient-ischemic-attack-and-minor-ischemic-stroke?search=tia&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1#H19
2. https://www.uptodate.com/contents/definition-etiology-and-clinical-manifestations-of-transient-ischemic-attack?search=transient%20ischemic%20attack&source=search_result&selectedTitle=2~150&usage_type=default&display_rank=2
3. https://www.ncbi.nlm.nih.gov/pubmed/24157557
4. https://www.ncbi.nlm.nih.gov/books/NBK459143/
5. https://www.uptodate.com/contents/differential-diagnosis-of-transient-ischemic-attack-and-acute-stroke?search=transient%20ischemic%20attack%20differential&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1#H10
6. https://www.uptodate.com/contents/transient-ischemic-attack-the-basics?search=tia%20diagnosis&topicRef=1123&source=related_link

Photo by Morgan Housel on Unsplash