12.11.09 Stroke prevention

Risk factors

• • BLOOD PRESSURE

    • RR x6-7

    • Target 130/80

    • Each 1 mmHg reduction => 3% risk reduction

      • Even if you're normotensive

  • AF

    • Warfarin => 70% risk reduction

  • Cholesterol

    • Only for ischaemic stroke

  • Good diabetes control

    • But usually the effect of this is more apparent for cardiovascular risk

  • Smoking

    • RR x2

    • Again, reduction of CV risk is the bigger effect

  • Exercise

    • 30 mins, 3 times a week

  • Carotid stenosis >70%

  • Diet

  • ARTERIAL thrombophilias

    • NOT e.g. Factor V Leiden, unless there's also a R=>L shunt

Arterial thrombophilias

• • Antiphospholipid syndrome

    • Autoimmune, hypercoagulable state caused by antibodies against cell-membrane phospholipids

      • Anticardiolipin antibodies, anti-β₂-glycoprotein 1 antibodies, lupus anticoagulant

  • Anticardiolipin antibodies

    • Found in several diseases including syphilis, antiphospholipid syndrome, livedoid vasculitis, vertebrobasilar insufficiency, Behçet's syndrome, idiopathic spontaneous abortion, and SLE

  • Lupus anticoagulant

    • Most patients with a lupus anticoagulant do not actually have lupus erythematosus

      • But patients with lupus erythematosus are more likely to develop a lupus anticoagulant than the general population

    • The term "anticoagulant" accurately describes its function in vitro, but in vivo, it functions as a coagulant

      • Antibodies interact with platelet membrane phospholipids, increasing adhesion and aggregation of platelets

      • But in vitro, it sequesters the phospholipid activators and so increases aPTT

Carotid endarterectomy

• • Useful within 12 weeks of stroke, if >70% narrowed

    • Otherwise risk outweighs benefit

    • Some benefit for 50-70% narrowing if done within 2 weeks

  • Open repair better than endovascular stenting due to risk of embolisation

    • Even when a sieve is in place

    • Open surgery uses a clamp so less risk

  • Careful of the nerves!

Notes

• • Haemorrhagic stroke => LOOK FOR A SECONDARY CAUSE

  • Lupus has four main types:

    • Systemic (SLE)

    • Discoid

    • Drug-induced

    • Neonatal

  • Rheumatoid factor is an against the Fc portion of IgG

  • Three main ANCA-associated vasculitidies:

    • Churg-Strauss syndrome

    • Microscopic polyangiitis

    • Wegener's granulomatosis

  • Anti-apolipoprotein H (AAHA) antibodies

    • AKA anti-β2 glycoprotein I antibodies

    • Subset of anti-cardiolipin antibodies and lupus anticoagulant

    • Strongly associated with thrombotic forms of lupus

    • Strongly implicated in autoimmune deep vein thrombosis

  • CREST syndrome: Calcinosis, Raynaud's phenomenon, Esophageal dysfunction, Sclerodactyly, Telangiectasias