Stroke PDF

Cerebrovascular accident(CVA) Dr.Sarah latif kazem Cerebral infarction is usually due to atherothromboembolism. The source of embolism can be the heart, particularly when there is AF, or the ruputure of large artery atherosclerosis and subsequent thromboembolism from carotid a...

Cerebrovascular accident(CVA) Dr.Sarah latif kazem Cerebral infarction is usually due to atherothromboembolism. The source of embolism can be the heart, particularly when there is AF, or the ruputure of large artery atherosclerosis and subsequent thromboembolism from carotid arteries, vertebral arteries and aortic arch. Occlusion of the small perforating lenticulostriate arteries in patients with sporadic or genetic small vessel diseases leads to ‘lacunar’ infarctions. (Ischemic stroke) Intracerebral haemorrhage The commonest cause of intracerebral haemorrhage is the rupture of small blood vessels. Small vessels can be damaged by hypertension, diabetes, amyloid deposition or genetic causes. Rupture of abnormalities of larger vessels such as arteriovenous or cavernous malformations, and sometimes intracranial aneurysms can also lead to intracerebral haemorrhage. Risk factors for stroke N0nmodified risk factors Age Sex (male > female) Previous vascular event:.Myocardial infarction.Stroke.Peripheral vascular disease Sickle cell disease Modified Risk factors Blood pressure Cigarette smoking High LDL cholesterol Diabetes mellitus  Atrial fibrillation Chronic kidney disease Excessive alcohol intake Oestrogen-containing drugs: Oral contraceptive pill Hormone replacement therapy Polycythaemia Drugs, e.g. cocaine Heart disease: Congestive cardiac failure Infective endocarditis Clinical features Symptoms can be transient ischemic stroke(TIA) or persistent (stroke). The symptoms of a typical stroke progress over minutes, affect an identifiable area of brain. The clinical syndrome of an ischaemic stroke depends on the arterial territory involved and the size of the lesion. The presence of a unilateral motor deficit, a higher cerebral function deficit such as aphasia , or a visual field defect usually places the lesion in the cerebral hemisphere. Ataxia, diplopia, vertigo or bilateral weakness usually indicates a lesion in the brainstemor, cerebellum. The combination of severe headache and vomiting at the onset of the focal deficit is suggestive of intracerebral haemorrhage. (Intracerebral hemorrhage) Investigations: Neuroimaging CT is the most widely available method of imaging the brain. It has reasonable sensitivity for some non-stroke lesions, such as subdural haematomas, subarachnoid haemorrhage and brain tumours. MRI scanning times are longer than CT, but MRI diffusion weighted imaging (DWI) can detect ischaemia earlier than CT. Cardiac investigations Approximately 20% of ischaemic strokes are due to embolism from the heart. The most common cause is atrial fibrillation, but prosthetic heart valves, endocarditis, other valve abnormalities and recent myocardial infarction may also lead to cardioembolis. A transthoracic or transoesophageal echocardiogram in selected stroke patients can identify endocarditis, atrial myxoma, intra-cardiac thrombus or patent foramen ovale (PFO). Blood tests Blood tests can identify high fasting glucose levels, anaemia, electrolyte disturbances or evidence of an inflammatory response (e.g. in temporal arteritis or vasculitis). Management 1-Reperfusion (thrombolysis and thrombectomy) Intravenous thrombolysis with recombinant tissue plasminogen activator (alteplase) improves recovery if given within 4.5 hours of symptom onset to carefully selected patients. Mechanical clot retrieval (thrombectomy) performed up to 6 hours after onset of symptoms can greatly improve the chances of avoiding disability in these patients. 2-Antiplatelet agents In the absence of contraindications, aspirin (300 mg daily) should be started immediately after a major ischaemic stroke 3-Blood pressure Haemorrhagic stroke: consider lowering systolic blood pressure to 130 140 mmHg and maintain this blood pressure for at least 7 days Ischaemic stroke: unless there is heart or renal failure, evidence of hypertensive encephalopathy or aortic dissection, do not lower blood pressure abruptly. Complications Epileptic seizures Depression and anxiety Painful shoulder Avoid traction injury Chest infection Constipation Urinary infection Pressure sores Deep vein thrombosis/pulmonary embolism Spasticity and contracture