TIA

Question 1

What are the different definitions of TIA?

Answer 1

1. Classical : Time based definition. Sudden onset of focal neurological symptoms resolving within 24 hours.
2. New: Tissue-based definition. Sudden onset of focal neurological symptoms which do not radiologically demonstrate ischemia.

Question 2

What are the limitations of tissue-based definition of TIA?

Answer 2

1. Dependency on sensitivity and availability of neuro-imaging
2. Selective use of neuro-imaging leads to unreliable population level estimates of TIA prevalence

Question 3

What is the estimated incidence of TIA from the Framingham Heart Study?

Answer 3

1.19 per 1000 person years

Question 4

What is the estimated overall prevalence of TIA among US adults?

Answer 4

2%

Question 5

What are the different mechanisms of TIA?

Answer 5

1. Embolic (large extracranial artery, aorta or heart)
2. Small vessel or lacunar
3. Large artery low flow

Question 6

What is the 90-Day risk of ischemic stroke among patients with typical and atypical TIAs?

Answer 6

10% and 11%

Question 7

What is the 10-year risk of ischemic stroke after typical and atypical TIA?

Answer 7

27% & 31%

Question 8

What is the ABCD2 score and what is it’s interpretation?

Answer 8

Age 60 or above = 1 point
Blood pressured 140 / 90 or above = 1 point
Clinical features: unilateral weakness 2 points, isolated speech 1 point, other 0 points
Duration: 60 minutes or more = 2 points, 10 - 59 minutes = 1 point, < 10 minutes = 0 Points
Diabetes = 1 point

Interpretation:
6-7 : High 2-day risk (8 percent)
4-5 : Moderate 2-day risk (4 percent)
0-3 : Low 2-day risk ( 1 percent)