Pathophysiology of Thrombosis and Embolism

Question 1

Describe the process of thrombosis

Answer 1

• Endothelial injury
• Static or turbulent blood flow: fibrin deposition, platelet clumping
• Hypercoagulability of blood
  (Virchow’s triad)
• Loss of intimal cells, denuded plaque
• Collagen exposed, platelets adhere
• Fibrin meshwork, platelets trapped
• Further turbulence and platelet deposition

Question 2

Explain the significance of Virchow’s triad

Answer 2

Changes in;
- Blood vessel wall
- Blood constituents
- Pattern of blood flow
A change in any of these factors can cause thrombosis.

Question 3

Explain the relationship between atheroma and thrombosis

Answer 3

Arterial thrombosis most commonly superimposed on atheroma (Virchow’s triad).

Question 4

List the factors causing thrombosis

Answer 4

• Thromboembolism
• Atheroma
• Spasm
• External compression
• Vasculitis
• Vascular steal: ischaemia caused by vascular access device

Question 5

List the factors causing embolism

Answer 5

• Cardiac failure
• Severe trauma/burns
• Post-op/post-partum
• Nephrotic syndrome
• Disseminated malignancy
• Oral contraceptive
• Old age
• Bedrest/immobilisation
• Obesity
• PMH of DVT
• Prophylaxis for surgical patients at risk e.g. heparin

Question 6

Describe the presentation of rheumatic heart disease

Answer 6

• ‘Flitting’: painful
• Polyarthritis of large joints
• Skin rashes
• Fever

Question 7

Describe the presentation of rheumatic heart disease

Answer 7

• ‘Flitting’: painful
• Polyarthritis of large joints
• Skin rashes
• Fever
• Murmur (acute pancarditis)

Question 8

Describe the presentation of rheumatic heart disease

Answer 8

• ‘Flitting’: painful
• Polyarthritis of large joints
• Skin rashes
• Fever
• Murmur (acute pancarditis)
• Aschoff body: chronic inflammatory cells, necrosis, activated macrophages

Question 9

Describe the PMH of rheumatic heart disease

Answer 9

• Recent sore throat with group A beta-haemolytic streptococci
• Causes strong antibody reaction
• Tissue damage to heart

Question 10

Describe the pathophysiology of rheumatic heart disease

Answer 10

Inflammation of endocardium and left sided valves –> necrosis of annulus/chordae tendinae –> stenosis/regurgitation

• Only cause of MS
• Can cause MR