Pathology

• What is thrombosis?

  A blood clot mass
• What is haemostasis?

  Blood clotting
• What is one function of haemostasis?

  Maintain normal blood flow
• How does the vascular wall contribute to haemostasis?

  It can constrict and stop bleeding
• What does the coagulation cascade do?

  Forms a strong haemostatic plug
• What is thrombosis formed from?

  It is a solid mass of blood constituents formed within the vascular system
• What can happen to a thrombus after it forms?

  It can fragment and be released
• What are the three predisposing factors for thrombosis?

  Endothelial injury, stasis/turbulence, hypercoagulability
• What does ECM stand for?

  Extracellular matrix
• How does stasis contribute to venous thrombosis?

  By slowing blood flow
• What happens in blood hypercoagulability?

  Clotting factors become hyperactive
• How does myocardial infarction increase thrombosis risk?

  Due to stasis and endothelial injury
• Why do prosthetic cardiac valves increase thrombosis risk?

  Surface causes coagulation of clotting factors
• Which of these is a high risk factor for thrombosis?

  Tissue injury
• How does increased age increase thrombosis risk?

  Decreased movement causes stasis
• What is arterial thrombosis most commonly superimposed on?

  Atherosclerosis
• Where are common sites for arterial thrombosis?

  Coronary, cerebral, and femoral arteries
• What can atheromas cause?

  Partial or complete arterial occlusion
• What can venous thrombosis cause?

  Pulmonary infarction
• Why can venous thrombosis be asymptomatic?

  Collateral bypass channels
• What does DVT stand for?

  Deep vein thrombosis
• How do valves increase chance of clotting?

  Generates turbulence damaging endothelial cells
• How to reduce DVT during long haul flight?

  Compression socks
• How to reduce DVT during long haul flight?

  Remain hydrated
• What are the possible fates of a thrombus?

  Propagation, immobilisation, dissolution, organisation
• What is immobilisation of a thrombus?

  Dislodging and travelling to other sites
• What is dissolution of a thrombus?

  The results of fibrinolysis
• What is organisation of a thrombus?

  Organised into a scar by macrophages
• What is an embolism?

  Thrombus comes off and travels in blood
• What can tissue infarction result in?

  Tissue death (gangrene)
• What does venous thrombosis result in?

  Congestion and oedema
• Thrombosis is caused by what?

  Over activation of haemostasis
• How is haemostasis regulated in normal vessels?

  Tightly regulated to maintain a clot-free state
• What are the three mechanisms that control haemostasis?

  Vascular wall, platelets, coagulation cascade
• What do platelets do in haemostasis?

  Aggregate and form a plug
• How does thrombosis differ from haemostasis?

  Thrombosis is pathological
• What happens when a thrombus is formed?

  It loosely attaches to the vessel wall
• Why is endothelial injury the most important factor?

  Exposes ECM, leading to platelet adhesion
• How does turbulence contribute to arterial thrombosis?

  It can damage the endothelial layer
• What is another name for blood hypercoagulability?

  Thrombophilia