TIA

Question 1

What is a transient ischaemic attack?

Answer 1

A transient episode of neurological dysfunction caused by focal brain, spinal cord or retinal ischaemia without acute infarction - Majority of TIAs resolve within first hours

Question 2

What is the aetiology of a transient ischaemic attack?

Answer 2

• In situ thrombosis of an intracranial artery or artery-to-artery embolism of thrombus as a result of stenosis or unstable atherosclerotic plaque - Cardioembolic events. Intracardiac thrombus may form in response to some secondary risk factor such as stasis from impaired ejection fraction of atrial fibrillation - Small-vessel occlusion. microatheromas, microatheromas, fibrinoid necrosis of small penetrating vessels are seen - Occlusion due to hypercoagulability, dissection, vasculitis, vasospasm or sickle cell occlusive disease

Question 3

What is the epidemiology of a transient ischaemic attack?

Answer 3

• 11% of all deaths in England and Wales - More common in males and individuals of non-Hispanic black race

Question 4

What are the presenting symptoms of a transient ischaemic attack?

Answer 4

• Patient/caregiver report of focal neurological deficit - Brief duration of symptoms - History of extracranial atherosclerosis - History of cardiac disease - No history of epilepsy - Absence of seizure prior to neurological deficit - History of migraine - Temporary loss of vision, aphasia, paraesthesia, hemiparesis

Question 5

What are the signs of a transient ischaemic attack on examination?

Answer 5

• Unilateral symptoms - Increased BP on presentation - Focal neurological deficit on examination - Absence of positive symptoms (shaking, scotoma, spasm) - Absence of headache

Question 6

What are the risk factors for a transient ischaemic attack?

Answer 6

• Atrial fibrillation - Valvular disease - Cigarette smoking - Alcohol abuse - Advanced age - Hypertension - Congestive heart failure - Carotid stenosis

Question 7

What are the investigations for transient ischaemic attack?

Answer 7

• Blood glucose: less than 3.3mmol suggests hypoglucaemia as mimic of TIA - Chemistry profile: very low or high sodium, potassium, or calcium suggests non-ischaemic cause of symptoms - FBC: usually normal - ECG: AF may be present - Brain MRI with diffusion: half will have positive diffusion images

Question 8

How is transient ischaemic attack managed?

Answer 8

• Antiplatelet therapy - Lipid lowering agent - Lifestyle modifications with or without antihypertensive therapy - Carotid endartectomy or stent - Lifestyle modifications

Question 9

What are the complications of a transient ischaemic attack?

Answer 9

• Stroke - MI

Question 10

What is the prognosis of a transient ischaemic attack?

Answer 10

• A patient with TIA has no residual symptoms from a primary event by definition - Most significant risk to the patient is a second ischaemic event causing permanent disability