From the Guidelines
A Transient Ischemic Attack (TIA) is a temporary interruption of blood supply to the brain, resulting in self-limited focal neurologic deficits with no permanent clinical deficit or demonstrated infarct on subsequent imaging.
Key Characteristics of TIA
- The symptoms of TIA are typically short-lived, often resolving within less than 1 hour 1
- The traditional time-based definition of TIA sets the maximum duration at 24 hours 1
- A newer imaging-based definition restricts the term TIA to those without neuroimaging evidence of tissue damage 1
Risk of Subsequent Stroke
- The risk of subsequent stroke after a TIA is high, with 8.8% at 7 days and 11.6% at 90 days 1
- In the setting of symptomatic carotid disease, the 90-day risk of ipsilateral stroke is 20.1% 1
- The risk of recurrent stroke is greatest in the first week, with a risk as high as 13% in the first 90 days after the initial event, and up to 30% within 5 years 1
Importance of Early Recognition and Management
- Early recognition of TIA, identification of patients at risk, and risk factor modification are important stroke prevention measures 1
- Timely initiation of secondary prevention medical therapy and carotid endarterectomy has been shown to significantly reduce the risk of major stroke after an initial TIA or nondisabling stroke 1
- The goal of outpatient management of TIA is rapid assessment and management to reduce the risk of a recurrent, possibly more serious, event 1
From the Research
Definition of Transient Ischemic Attack (TIA)
- A TIA is a transient episode of neurological dysfunction caused by focal brain, spinal cord, or retinal ischemia, without acute infarction 2
- It is a brief episode of dysfunction in a confined area of the brain, with symptoms lasting less than 24 hours 3
- TIA is also defined as a self-resolving focal cerebral ischemia with symptoms lasting less than 24 hours, and no evidence of acute brain tissue infarction 4
Risk Factors and Causes of TIA
- Risk factors for TIA include family history of stroke or TIA, age above 55 years, higher risk in males, high blood pressure, diabetes mellitus, tobacco smoking, genetics, race, and imbalance in lipid profile 5
- The risk of ischemic stroke following a TIA is directly related to its etiopathogenesis, and recognizable causes are commonly categorized within one of three domains: cerebrovascular pathology, cardiac dysfunction, and hematologic disorders 6
Diagnosis and Evaluation of TIA
- Diagnosis of TIA is based on a thorough history and physical examination, and several radiological tests such as computed tomography and magnetic resonance imaging are useful in the evaluation of patients who have had a TIA 5
- Neuroimaging evaluation within 24 hours of symptom onset, preferably with magnetic resonance imaging, including diffusion sequences, is recommended 2
- Noninvasive imaging of the cervical vessels and intracranial vessels, electrocardiography, and routine blood tests are also reasonable diagnostic approaches 2
Treatment and Management of TIA
- Early diagnosis and treatment is critical to reduce mortality and risk of stroke in patients who have experienced a TIA 3
- Urgent assessment and initiation of treatment of TIA is an effective strategy in reducing the incidence of stroke 3
- Treatment following acute recovery from a TIA depends on the underlying cause, and may include carotid endarterectomy surgery for patients with more than 70% stenosis of the carotid artery 5