Venous Thrombosis Flashcards
What arterial thrombotic events can occur?
Arterial - coronary, cerebral, peripheral
Venous - Deep vein thrombosis, PE
Describe arterial thrombosis?
High pressure system
Artherosclerosis
Platelet rich thrombus
How do you treat an arterial thrombosis?
Aspirin and other anti-platelet drugs
Modify risk factors for atherosclerosis
Describe venous thrombosis?
Low pressure system
Platelets not activated
Activates coagulation cascade - rich in fibrin clot
What is Virchow’s Triad?
Stasis
Vessel wall
Hyeprcoagulability
How do you treat a venous thrombosis?
Heparin
Warfarin
New oral anticoagulants
What are clinical features of a Deep Vein Thrombosis?
Limbs feel hot, swollen and tender
Pitting Oedema
What are features of a Pulmonary Embolism?
Pulmonary infarction Pleuritic chest pain Cardiovascular collapse/death Hypoxia Right heart strain
What are risk factors for Venous thrombosis? (11…lol)
Age Marked obesity Pregnancy Puerperium Oestrogen therapy Previous DVT/PE Trauma/surgery Malignancy Paralysis Infection Thrombophilia
What are the components of normal haemostatic system?
Formation of platelet plug (Primary)
Formation of fibrin clot (Secondary)
Fibrinolysis
Anticoagulant defences
What is thrombophilia?
Familial or acquired disorders of the haemostatic mechanism which are likely to predispose to thrombosis
What are potential mechanisms of thrombophilia?
Increased coagulation activity - platelet plug/fibrin clot formation
Decreased fibrinolytic activity
Decreased anticoagulant activity
Name some Hereditary thrombohilias? (5)
Factor V Leiden Prothrombin 20210 mutation Antithrombin deficiency Protein C deficiency Protein S deficiency
Name 3 naturally occurring anticoagulants
Serine Protease Inhibitors
Protein C
Protein S
When would you consider hereditary thrombophilia screening?
Venous thrombosis <45 years old
Recurrent venous thrombosis
Unusual venous thrombosis
FHx of venous thrombosis or thrombophilia
What is the management of Hereditary Thrombophilia?
Advice on avoiding risk
Short term prophylaxis
Short term anticoagulation
Ling term anticoagulation
What is a type of acquired thrombophilia?
Antiphospholipid antibody syndrome
What are features of antiphospholipid antibody syndrome?
Recurrent thrombosis - arterial, including TIA’s., venous
Recurrent fetal loss
Mild thrombocytopenia
What is the pathogenesis of antiphospholipid antibodies?
Antibodies lead to a conformational change in beta2 glycoprotein 1 which leads to activation of both primary and secondary haemostasis ad vessel wall abnormalities
In antiphospholipid syndrome, what are the autoantibodies specific for?
Anionic phospholipids and which prolong phospholipid dependant coagulation tests in vitro (Lupus anticoagulants)
What other conditions are associated with antiphospholipid antibodies?
Autoimmune disorders Lymphoproliferative disorders Viral infections Drugs Primary
What are treatments of anti-phospholipd syndrome?
Activation of both primary and secondary haemostasis
Arterial and venous thrombosis - aspirin + warfarin
