Thrombotic Disorders Flashcards
Name the elements of haemostasis
- Primary haemostasis
- Blood coagulation
- Fibrinolysis
What are the steps in primary haemostasis?
- Vasoconstriction
- Platelet adhesion
- Platelet aggregation
What is a thrombus?
A clot arising in the wrong place
List the components of Virchow’s triad (thrombosis)
- Statis
- Vessel damage
- Hypercoagulability
Name the risk factors for thrombosis
- Bed rest
- Travel
- Pregnancy
- Trauma
- Atherosclerosis
Name the three types of thrombosis
- Arterial
- Venous
- Microvascular
Describe the features of an arterial thrombus
- White clot: platelets and fibrin
- Results in ischaemia and infarction
- Principally secondary to atherosclerosis
Give examples of arterial thromboembolism
- MI
- Unstable angina
- Stroke
- TIA
- Limb ischaemia
What are the risk factors for arterial thrombosis?
- Age
- Smoking
- Sedentary lifestyle
- Hypertension
- Diabetes
- Obesity
- Hypercholesterolaemia
How can arterial thrombosis be managed?
- Primary prevention: lifestyle modifications and treatment of vascular risk factors
- Acute presentation: thrombolysis and antiplatelet/anticoagulant drugs
- Secondary prevention
Describe the features of a venous thrombus
- Red thrombus: fibrin and red cells
- Results in back pressure
- Principally due to stasis and hypercoagulability
Give examples of venous thromboembolism
- DVT
- PE
- Visceral venous thrombosis
- Intracranial venous thrombosis
- Superficial thrombophlebitis
What are the risk factors for venous thromboembolism?
- Increasing age
- Pregnancy
- Hormonal therapy
- Tissue trauma
- Immobility
- Surgery
- Obesity
- Systemic disease
- FH
Which systemic diseases can increase the risk of venous thrombosis
- Cancer
- Myeloproliferative neoplasm
- Autoimmune disease: IBD, connective tissue disease e.g. SLE and antiphospholipid syndrome (causes arterial and venous thrombosis)
How can a suspected diagnosis of venous thrombosis be made?
- Probability score: Wells or Geneva score
- D-dimer if probability score is low
- Imaging: doppler, V/Q scan, CT pulmonary angiogram etc.
What are the management options for venous thromboembolism?
- Anticoagulants: LMWH, warfarin and DOACs
- Thrombolysis only in selected cases (massive PE etc.)
What is heritable thrombophilia?
An inherited predisposition to venous thrombosis
Give 2 examples of common heritable thrombophilias
- Factor V Leiden
- Prothrombin G20210A
Give 3 examples of heritable thrombophilia
- Antithrombin deficiency
- Protein C deficiency
- Protein S deficiency
Describe the features of microvascular thrombus
- Platelets and/or fibrin
- Results in diffuse ischaemia
- Principally in disseminated intravascular coagulation (DIC)
What are the features of DIC?
- Diffuse systemic coagulation activation
- Occurs in septicaemia, malignacy and eclampsia
- Causes tissue ischaemia: gangrene and organ failure
- Consumption of platelets and clotting factors leading to bleeding
