Thrombosis

Question 1

Definition of a thrombus

Answer 1

Clot arising in the wrong place

Question 2

Definition of a thromboembolism

Answer 2

Movement of a clot along a vessel

Question 3

3 sides of Virchow’s triad

Answer 3

• Vessel damage
• Hypercoagulability
• Stasis

Question 4

What is Virchow’s triad

Answer 4

3 broad categories that contribute to thrombosis

Question 5

Examples of each side of Virchow’s triad

Answer 5

Vessel damage
-Artherosclerosis

Hypercoagulability

• Pregnancy
• trauma

Stasis

• Bed rest
• Travel

Question 6

3 types of thrombosis

Answer 6

• Arterial
• Venous
• Microvascular

Question 7

What causes an arterial thrombus and what is the result of it

Answer 7

-“white clot” = Platelets + fibrin
-Ischaemia + infarction
(usually secondary to artherosclerosis

Question 8

3 types of arterial thromboembolism

Answer 8

• Coronary thrombosis (MI/unstanble angina)
• Cerebrovascualr thromboembolism (Stroke/TIA)
• Peripheral embolism (Limb ischaemia)

Question 9

Risk factors for arterial thrombosis

Answer 9

• Age
• Smoking
• Sedentary lifestyle
• Hypertension
• Diabetes mellitus
• Obesity
• Hypercholesteroaemia

Question 10

Management of arterial thrombosis

Answer 10

Primary prevention

• Lifestyle modification
• Rx of vascular risk factors

Acute presentation

• Thrombolysis (TPA, tissue plasminogen activator)
• Antiplatelet/anticoagulant drugs (Clopidogrel/warfarin)

Secondary prevention (clopidogrel + warfarin(if AF) )

Question 11

What causes a venous thrombus and what is the resutl

Answer 11

-Red thrombus = Fibrin + RBC
-Results in back pressure
(usually due to stasis + hypercoagulability)

Question 12

2 types of venous thromboembolism (VTE)

Answer 12

• Limb DVT
• Pulmonary embolism (PE)
• Visceral venous thrombosis
• Intracranial venous thrombosis
• Superficial thrombophlebitis

Question 13

Risk factors for venous thrombosis

Answer 13

• Age
• Pregnancy
• Obesity
• Surgery
• Hormonal therpay (COCP/HRT)
• Immobility
• Tissue trauma
• FHx
• Systemic disease

Question 14

3 systemic diseases that increase risk of VTE

Answer 14

• Cancer
• Myeloproliferative neoplasm (MPNs)
• Auto-immune diseases (IBDs, connective tissue disease e.g. SLE)

Question 15

Investigations to diagnose a VTE

Answer 15

• D-dimer

- Doppler US or CTPA or V/Q scan

Question 16

Rx of VTEs

Answer 16

Anticoagulants

• LMWH
• Warfarin
• DOACs (direct oral anticoagulant)

Thrombolysis in selected cases e.g. Massive PE

Question 17

What causes a microvascular thrombus and what’s the result

Answer 17

-Platelets +/- fibrin (?sickle RBCs in sickle cell disease?)
-Diffuse ischaemia
Usually in DIC

Question 18

What is DIC and when does it happen

Answer 18

-Disseminated Intravascular Coagulation 
Occurs in:
-Septicaemia 
-Malignancy 
-Eclampsia

Question 19

What does DIC cause and what causes it

Answer 19

DIC causes:

• Gangrene (?ischaemia first?)
• Organ failure

Caused by consumption of platelets + clotting factors leading to bleeding (cause there’s no more platelets or clotting factors left)