TIA AND STROKE. Topics/Order of the day 1. Topics/Order of the day 2 01/08/2012

Transcription

1 Charles Ashton Medical Director TIA AND STROKE Topics/Order of the day 1 What Works? Clinical features of TIA inc the difference between Carotid and Vertebral territories When is a TIA not a TIA TIA management and Stroke prevention (BP Antiplatelet, Statin, Carotid surgery and AF Thrombolysis and Stroke units The place of Neurosurgery Topics/Order of the day 2 Imaging Carotid Surgery AF and CHADS 2 score Cost /Commissioning issues New advances Take Home Messages MCQ 1

2 Stroke Treatments/Prevention Thrombolysis Acute Stroke Units Anticoagulation Antiplatelets Antihypertensives Statins Smoking Cessation Closing PFO s Carotid Endarterectomy Exercise, weight, alcohol Acute Stroke Units Reduce Mortality by 28% (Langhorne 1993) Work by Improved general care? Reduce damage at ischaemic penumbra Thrombolysis IV recombinant Tissue Plasminogen Activator (TPA) Haemorrhage must be excluded Little or no benefit after 4.5 hours NNT at 1 hour 4 and at 3 hours 16 Causes up to 5% deaths due to IC bleeds No Mortality benefits Reduce Disability and proportion patients with No disability from about 35% to 27% Works best in moderately severe strokes 2

3 Contraindications Any evidence of intracerebral haemorrhage Severe Hypertension (>180 systolic or >100 diastolic) Siezures History of AVM Recent Surgery Stroke within 3 months Contraindications 2 Patients older than 80 years All patients taking oral anticoagulants are excluded regardless of international normalized ratio (INR) Patients with baseline National Institutes of Health Stroke Scale score 25 Patients with a history of both prior stroke and diabetes 3

4 Intracerebral Bleed Middle Cerebral Infarct Neurosurgery Very rarely required Massive infarction of a cerebral hemisphere may need decompression Occasionally intracerebral haemorrhage with mid line shift (little evidence) Hydrocephalus 4

5 Anterior Cerebral Artery Signs and Symptoms: Weakness (may be mono paresis) Extra pyramidal symptoms (tremor) Apraxia Sensory loss in same distribution as weakness Mood/personality changes Incontinence Aphasia Middle Cerebral Artery Infarction Symptoms and Signs Dysphasia (if Left hemisphere involvement) Dyslexia Dysgraphia Contralateral Hemiparesis or Hemiplegia Contralateral hemisensory disturbance Rapid progression in Decreased Level of Consciousness Vomiting Homonymous Hemianopia Denial or lack of recognition of paralyzed extremity Eyes look toward lesion Inability to turn eyes toward the affected side Posterior Cerebral Artery Central Signs and Symptoms: Central Thalamic or subthalamic nuclei involvement Diffuse sensory loss Mild Hemiparesis Intention Tremor Cerebral peduncle involvement Contralateral Hemiplegia Oculomotor Nerve deficit Brainstem involvement Pupillary dysfunction Nystagmus Loss of conjugate gaze 5

6 Posterior Cerebral Artery (Peripheral) Signs and Symptoms: Peripheral Visual Changes Homonymous hemianopia Cortical blindness Lack of depth perception Failure to see objects not centered in visual field Visual hallucinations Memory deficits Perseveration Dyslexia Plaque Ulceration 6

7 Express Study Early use of Existing Preventive Strategies for Stroke After minor Stoke or TIA 10% one week risk of recurrent stroke Early intervention reduced risk by 80 % The most effective single intervention was carotid endarterectomy which reduced risk by 75% on its own Predicted effect of treatment Based on RCTs of long term treatment Most patients Relative Risk Reduction Aspirin 20% Statin 20% Blood pressure lowering 30% Some patients Warfarin 50% Carotid Endarterectomy 75% (Aspirin + Clopidogrel?) Total >80% CHADS 2 Score for AF d the CHADS2 score system Congestive heart failure Hypertension Age > 75 years Diabetes Stroke previous history of stroke or TIA Presence of any of the above adds 1 to the score except for previous history of stroke which adds 2 7

8 ABCD Score Used to predict the risk of stroke during the first seven days after a TIA. Researchers found there to be over 30% risk of stroke in TIA patients with an 'ABCD score' of six, as compared to no strokes in those with a low ABCD score. ABCD Score A Age of patient Age >/= 60 1 Age < 60 0 B Blood pressure at SBP > 140 or DBP >/= 90 1 Assessment Other 0 C Clinical Features Unilateral weakness 2 presented with Speech disturbance (no weakness) 1 Other 0 D Duration of TIA >/= 60 minutes 2 symptoms minutes 1 <10 minutes 0 TOTAL 6 8

9 What is a TIA? Transient full recovery in 24 hours Brain infarction occurs after 1 hour Loss of function Corresponds to a vascular territory Lobes have mixed vascular territories When is a TIA not a TIA? When you don t know when it begins and ends When it lasts more than 24 hours When there is no focal neurological deficit When the main symptom is LOC although this can be a part of posterior circulation TIA s When a patient with a Stroke gets tired 9

10 Carotid TIA Limb weakness Dysphasia Amaurosis Fugax Mono Ocular Blindness NOT loss of consciousness NOT sensory loss Vertebral TIA Dysarthria Sensory Changes Hemianopia Vertigo LOC Dysphagia Nystagmus Nausea and Vomiting Needs to have 2 or more of the above More like to have cardiac source 10

11 Pure Sensory TIA s Pure or predominantly sensory transient ischaemic attacks are uncommon Angiography demonstrates focal stenoses in the proximal portion of the posterior cerebral artery (PCA). ps TIAs strongly suggest the presence of PCA disease. Repeated compromise of small vessels supplying the posterior lateral part of the thalamus Investigations FBC Thrombocythaemia Polycythaemia U&E LFT s ECG AF Dopplers, MRA, DSA CT scan will be normal Diffusion weighted MRI abnormal early on Transthoracic Echo Transoesophageal Echo Bubble contrast echo for PFO 24 hour tape (occasionally) Imaging in TIA CT should be normal Standard MRI should be normal Diffusion weighted MRI will confirm diagnosis (if done early) Exclusion of Carotid stenosis > 75 % most important 11

12 Bubble Contrast Echo Antiplatelet Therapy (NICE 2011) TIA 1 st line Clopidogrel 75mg (indefinite) 2 nd line Aspirin 75mg (indefinite) Stroke (after 2/52 300mg od Aspirin) 1 st line Clopidogrel 75mg (indefinite) 2 nd line Aspirin and Dyridamole SR 12

13 PFO Closure Device Statins Relatively disappointing for Stroke prevention No evidence of benefit older than 80 (Prosper Study) Otherwise follow NICE targets of 4mmol/l TC and 2mmol/l LDL if obtainable with generic Statin if not the old targets of 5mmol/l TC and 3mmol/l LDL The Future Immediate DWI MRI Endovascular photoacoustic recanalization Intra arterial thrombolysis Mechanical clot removal Factor Xa inhibitors Dibagitran etc 13

14 Payment by Results? How are outpatients costs worked out? Take Home Points TIA diagnosis is clinical (take a good history) Around 50 % of referrals to TIA clinics aren t TIA The concept of Acute brain attack Most of the secondary prevention can be done in general practice ASAP Carotid endarterectomy for >75% stenosis is very important We don t anticoagulate enough AF patients 14