TIA

• TIA: a clinical syndrome characterised by an acute loss of focal cerebral or ocular function with symptoms lasting <24 hr
• Crescendo TIAs are >1 TIA within 1 week
• Frequent TIAs are those occurring at least once per week
• Treat any patient presenting acutely with focal neurological signs as a stroke
• if within <4 hr of symptom onset, consider for thrombolysis
• see Acute Stroke guideline
• Diagnose a TIA only once symptoms have resolved in less than 24hrs
• majority of TIA resolve in 90 minutes
• TIA is more difficult to diagnose than stroke:
• try to obtain a witness account
• syncope is unlikely to be a TIA
• vertigo alone is unlikely to be a TIA

Symptoms and signs

Anterior circulation

• Dysphasia
• Dysarthria
• Visuospatial neglect
• Usually hemiparesis (face, arm and leg)
• Usually hemisensory (face, arm and leg)

Posterior circulation (ischaemia in brainstem, cerebellum and/or occipital lobes)

• Nausea and vomiting
• Vertigo
• Diplopia
• Ataxia
• Crossed syndromes (weakness or numbness on side of face and in contralateral limbs)
• Coma
• Visual field defect (Homonymous hemianopia)

Stroke risk

• Use ABCD2 score to classify chance of stroke within 7 days as ‘low’ or ‘high’
• treat all patients with TIA who are in atrial fibrillation (AF) as high risk TIA
• treat crescendo TIAs (>1 TIA within 1 week) as high risk, even if ABCD2 score <4

ABCD2 score including AF and crescendo TIA

Immediate investigations

• FBC, clotting, ESR
• Random blood glucose
• U&E
• Random cholesterol
• ECG

Carotid Doppler and CT brain (plain)

• Request for all patients; urgently for high risk TIA
• Where vascular territory or pathology is uncertain, request a diffusion weighted MRI scan

When

• Unless you STRONGLY suspect a haemorrhagic stroke (severe headache, loss of consciousness) or BP very high (>180/100), begin antiplatelet and other therapy immediately

What

• Atorvastatin 20 mg straightaway and then each night regardless of the cholesterol value – non-HDL <40%
• if intolerant to statin, ezetimibe 10 mg daily
• If patient’s blood pressure in the TIA clinic is >130/80, start antihypertensive treatment
• do not wait for repeated measurements by the GP

Antiplatelet therapy

• First line: Clopidogrel 300 mg as loading dose then 75 mg daily monotherapy indefinitely
• if patient not able to tolerate clopidogrel, give aspirin 300 mg stat followed by aspirin 75 mg/day and dipyridamole 200 mg MR twice daily
• if both clopidogrel and dipyridamole contraindicated, offer aspirin 300 mg stat followed by aspirin 75 mg once daily
• if both clopidogrel and aspirin contraindicated or not tolerated, offer dipyridamole 200 mg
  MR twice daily
• Combination of clopidogrel and aspirin is not recommended for long-term prevention after stroke or TIA, unless there is another indication e.g. acute coronary syndrome or recent coronary stent procedure
• If dyspepsia experienced with Clopidogrel/aspirin, consider adding proton pump inhibitor
• try to avoid omeprazole, esomeprazole as they reduce the efficacy of Clopidogrel

Patient in AF

• Discuss with patient options for both warfarin (vitamin K antagonist) and non-vitamin K antagonist oral anticoagulation (DOAC)
• base choice on clinical features, patient preferences and risk
• use CHADS-VASc to assess stroke risk and HAS-BLED to assess bleeding risk. See Atrial fibrillation guideline
• choices of anticoagulation include warfarin, apixaban, dabigatran etexilate, edoxaban and rivaroxaban

DOAC initiation

• Screen patient – U&Es, LFTs, FBC, BP, renal function
• always check calculated creatinine clearance and follow prescribing guidelines for each DOAC
• For review and follow-up below, refer to the atrial fibrillation stroke prevention team

Warfarin Initiation

• Start therapeutic dose of LMWH. See Dalteparin for VTE guideline
• Unless there are contraindications, slow anticoagulation with warfarin will be started by the TIA service after assessing risk stratification and contraindications
• aim for an INR of 2–3
• stop antiplatelet agents once target INR achieved
• once INR >2, stop LMWH
• Discuss a clear treatment plan with patient and teach them how to administer LMWH
• Refer patient to the anticoagulation management service (AMS) for long-term follow-up

Patient already on warfarin

• If patient is on warfarin and developed a TIA with sub-therapeutic INR (<2), give treatment dose LMWH until INR >2
• If patient is already on warfarin with sub-therapeutic INR and time in therapeutic range (TTR) <65%, consider switching to DOAC if compliance and adherence is not an issue
• contact anticoagulation management service (AMS) to investigate TTR

• For patients with crescendo TIA, frequent TIA, BP uncontrolled or if symptoms unresolved when assessment completed, seek advice from stroke consultant of the day
• For those referred to TIA service, provide patient with drugs sufficient until appointment time and letter to GP 

Patient advice

• If smoking, advise to stop
• Advise patient on healthy lifestyle
• Advise patient not to drive until symptom-free for 1 month and to inform insurance company
• Advise all patients with definite clinical symptoms of TIA who are otherwise fit to dial 999 if they experience any new TIAs lasting more than a few minutes

• This will be undertaken by TIA/Stoke specialist
• Check NASECT criteria for carotid stenosis
• Where patients have repeated attacks of transient neurological symptoms despite best medical treatment, and an embolic source has been excluded, consider an alternative neurological diagnosis

Symptomatic carotid stenosis of 50–99%

• Assess and refer for carotid endarterectomy within 1 week of onset of symptoms
• Receive best medical treatment
• lifestyle and diet advice, including smoking cessation
• hypertension – aim for a target BP <130/80 mmHg but do not reduce abruptly
• diabetes mellitus – aim for HbA_1c <53 mmol/mol
• oral contraceptive pill or hormone replacement therapy contraindicated
• aim for total cholesterol <4 mmol/L and low-density lipoprotein (LDL) <2 mmol/L
• Advise all patients with definite clinical symptoms of TIA who are otherwise fit to dial 999 if they experience any new TIAs lasting more than a few minutes
• Calculate the 1 yr and 5 yr stroke risk
• Discuss all cases with vascular surgeon of the week
• Following risk assessment, discuss case in the vascular MDT
• Discuss management plan with patient (carotid endarterectomy vs medical management)

Symptomatic carotid stenosis of <50%

• Not to undergo surgery
• Receive best medical treatment
• lifestyle and diet advice, including smoking cessation
• hypertension – aim for a target BP <130/80 mmHg but do not reduce abruptly
• diabetes mellitus – aim for HbA_1c <53 mmol/mol
• oral contraceptive pill or hormone replacement therapy contraindicated
• aim for total cholesterol <4 mmol/L and low-density lipoprotein (LDL) <2 mmol/L
• Advise all patients with definite clinical symptoms of TIA who are otherwise fit to dial 999 if they experience any new TIAs lasting more than a few minutes

• Consider enrolment in a research study