Preventing strokes: the assessment and management of people with transient ischaemic attack

This review is a summary of the New Zealand guideline for the management of Transient Ischaemic Attack (TIA). TIA is a medical emergency and warrants urgent attention. The risk of early stroke following TIA may be as high as 12% at 7 days, and 20% at 90 days, with half of these strokes occurring within the first 48 hours. All people with suspected TIA should be assessed at initial point of health care contact for their risk of stroke. Diagnosis of TIA is more likely to be correct if the history confirms: sudden onset of symptoms, with maximal neurological deficit at onset; symptoms typical of focal loss of brain function such as unilateral weakness or speech disturbance; and rapid recovery, usually within 30-60 minutes. The ABCD2 score is a tool that assists with diagnosis and identifies people most at risk of stroke after TIA. People at high risk of stroke require urgent specialist assessment as soon as possible but definitely within 24 hours. This includes those with ABCD2 scores of 4 or more, crescendo TIAs, atrial fibrillation, or who are taking anticoagulants. People at low risk usually require specialist assessment and investigations within 7 days. This includes those with ABCD2 scores of less than 4 or those who present more than one week after TIA symptoms. As soon as the diagnosis is confirmed, all people with TIA should have their risk factors addressed and be established on an appropriate individual combination of secondary prevention measures including anti-platelet agents, blood pressure-lowering therapy, statin, warfarin (if atrial fibrillation or other cardiac source of emboli), and nicotine replacement therapy or other smoking cessation aid. Urgent assessment and intervention in TIA clinics has been shown to reduce the risk of stroke after TIA by up to 80%. Follow-up, either in primary or secondary care, should occur within 1 month so that medication and other risk factor modification can be reassessed.