From the Guidelines
The risk of stroke following a transient ischemic attack (TIA) is approximately 5.2% at 7 days, as demonstrated by a meta-analysis from 2007 1. This risk is particularly elevated in the first 48 hours, when about half of these early strokes occur. The recent TIAregistry.org project reported a stroke rate of 2.1% at 7 days, highlighting the importance of urgent evaluation and treatment in specialized stroke centers 1. Patients who have experienced a TIA should be evaluated urgently, ideally within 24 hours, and started on appropriate preventive therapy immediately. This typically includes antiplatelet therapy such as aspirin, clopidogrel, or a combination of aspirin and extended-release dipyridamole, as well as high-dose statins like atorvastatin 80 mg daily, regardless of baseline cholesterol levels 1. Blood pressure management is crucial, with a target below 140/90 mmHg for most patients, and risk stratification tools like the ABCD² score can help identify patients at highest risk 1. Carotid imaging should be performed promptly to identify significant stenosis that might require surgical intervention, and atrial fibrillation should be ruled out, as its presence would necessitate anticoagulation rather than antiplatelet therapy 1. The high early stroke risk following TIA underscores the importance of considering these events as medical emergencies requiring immediate attention and intervention. Key considerations in management include:
- Urgent evaluation and treatment in specialized stroke centers
- Initiation of antiplatelet therapy and high-dose statins
- Blood pressure management with a target below 140/90 mmHg
- Risk stratification using tools like the ABCD² score
- Prompt carotid imaging and ruling out atrial fibrillation.
From the Research
Risk of Stroke after TIA
- The risk of stroke is highest in the first week following a transient ischemic attack (TIA) 2, 3, 4.
- Studies have reported that the risk of recurrent stroke after a TIA can be as high as 5-10% within the first week 2, 3.
- Factors that increase the risk of early stroke recurrence include age, elevated blood pressure, clinical symptoms of motor weakness or speech disturbance, and large vessel atherothrombotic mechanism 2.
- The ABCD score, which includes factors such as age, blood pressure, clinical symptoms, and duration of symptoms, has been developed to predict the risk of stroke recurrence after TIA 3.
- Other scores, such as the ABCD(2), ABCD(2)I, and ABCD(3), have also been developed to predict the risk of stroke recurrence after TIA 3.
Timing of Stroke Risk after TIA
- The risk of stroke is elevated in the first 48 hours after TIA 4.
- The risk of stroke after TIA is 9.5% at 90 days and 14.5% at 1 year 4.
- The risk of combined stroke, myocardial infarction, or death is 21.8% at 1 year 4.
Prevention of Stroke after TIA
- Antithrombotic drugs, such as aspirin, clopidogrel, and extended-release dipyridamole, can be used to prevent recurrent stroke in patients with TIA 5.
- Combination antiplatelet therapy with clopidogrel and aspirin may reduce the rate of recurrent stroke during the first 3 months after a minor ischemic stroke or high-risk TIA 6.
- However, combination antiplatelet therapy also increases the risk of major hemorrhage 6.