Transient Ischemic Attack (TIA)
- A transient episode of neurologic dysfunction due to focal brain, retinal, or spinal cord ischemia without acute infarction
- Major predictor of stroke: 7.5–17.4% of patients with transient ischemic attack (TIA) experience a stroke within 3 months (1). 15% of patients with stroke report recent TIA.
- Synonym(s): ministroke
- Prevalence of TIA in general population: ~2%
- Predominant age: Risk increases >60 years of age; highest in 7th and 8th decades of life
- Predominant sex: male > female
- Predominant race/ethnicity: African Americans > Hispanics > Caucasians
Etiology and Pathophysiology
Temporary reduction/cessation of cerebral blood flow adversely affecting neuronal function
- Carotid/vertebral atherosclerotic disease (artery-to-artery thromboembolism, low-flow ischemia)
- Lacunar infarcts: small, deep vessel disease associated with hypertension (HTN) and diabetes
- Embolism secondary to the following:
- Valvular (mitral valve) pathology
- Mural hypokinesias/akinesias with thrombosis (acute anterior MI/congestive cardiomyopathies)
- Cardiac arrhythmia (atrial fibrillation accounts for 5–20% incidence)
- Hypercoagulable states (antiphospholipid antibodies, increased estrogen [e.g., oral contraceptives], pregnancy and parturition)
- Arteritis (vasculitis)
- Sympathomimetic drugs (e.g., cocaine)
- Other causes: spontaneous and posttraumatic (e.g., chiropractic manipulation) arterial dissection
- Fibromuscular dysplasia
Inheritance is polygenic, with tendency to clustering of risk factors within families.
- Older age (i.e., >60 years old)
- HTN, cardiac diseases (atrial fibrillation, MI, valvular disease)
- Atherosclerotic disease (carotid/vertebral stenosis)
- Obesity, diabetes, hyperlipidemia
- Cigarette smoking
- Lifestyle changes
- Control of medical risk factors: diabetes, HTN, hyperlipidemia
- Anticoagulation when high risk of cardioembolism (e.g., atrial fibrillation, mechanical valves)
- Improved blood pressure (BP) control has been very useful, with antiplatelet therapy being key for preventing recurrence if previous TIA (2)
- 1.5–3.5% risk of stroke in first 48 hours after TIA
- Up to 40% of patients with stroke have history of TIA
- Older patients have a higher mortality rate—highest in 7th and 8th decades.
- Atrial fibrillation is a frequent cause among the elderly.
- Congenital heart disease is a common cause among pediatric patients.
- Genetic: Marfan syndrome, moyamoya, or sickle cell disease
- Preeclampsia, eclampsia, and HELLP syndrome
- Thrombotic thrombocytopenic purpura (TTP) and hemolytic uremic syndrome
- Postpartum angiopathy
- Cerebral venous thrombosis
- Hypercoagulable states related to pregnancy
Commonly Associated Conditions
- Atrial fibrillation, uncontrolled HTN
- Carotid stenosis
- Some disease processes mimic TIA presentation (seizures, migraines, metabolic disturbances, syncope, multiple sclerosis); difference: gradual onset with nonspecific symptoms (headache, memory loss) versus acute onset with specific neurologic deficits (TIA)
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