STEP 1 — MCQs (NO answers here)

MCQ 1 — General Clinical Significance

The clinical impact of a thrombus depends mainly on:

a. The age of the patient

b. The site of thrombosis

c. The color of the thrombus

d. The size of the vessel wall

e. Whether inflammation is present

MCQ 2 — Main Danger of Venous Thrombi

Venous thrombi are most dangerous because they:

a. Cause severe arterial infarction

b. Frequently cause varicose veins

c. Can embolize to the lungs and cause death

d. Always cause gangrene

e. Never cause symptoms

MCQ 3 — Main Danger of Arterial Thrombi

Arterial thrombi are most clinically significant because they:

a. Cause congestion and edema

b. Are rich in red cells

c. Most commonly obstruct vessels such as coronary and cerebral arteries

d. Rarely occlude vessels

e. Only form in veins

MCQ 4 — Superficial Venous Thrombi

Superficial venous thrombosis (e.g., saphenous system) is characterized by:

a. High risk of embolization

b. Rarely causing symptoms

c. Local pain, congestion, swelling, and risk of skin infections/ulcers

d. Complete asymptomatic presentation

e. Strong association with pulmonary embolism

MCQ 5 — Deep Venous Thrombosis (DVT)

Which of the following is TRUE regarding DVTs in popliteal, femoral, or iliac veins?

a. They rarely embolize

b. They are symptomatic in almost all cases

c. They are prone to embolization and may be silent in ~50% of cases

d. They occur only in the upper limb

e. They are unrelated to stasis

MCQ 6 — DVT Risk Factors

All of the following predispose to lower-limb DVT EXCEPT:

a. Immobilization/bed rest

b. Congestive heart failure

c. Trauma or surgery

d. Late pregnancy and postpartum period

e. Hyperthyroidism

MCQ 7 — Cancer-Associated Thrombosis

Migratory thrombophlebitis (Trousseau syndrome) is caused mainly by:

a. Immune complex deposition

b. Tumor-derived procoagulant factors

c. Infection

d. Vitamin C deficiency

e. Loss of fibrinogen

MCQ 8 — Pregnancy-Related DVT Mechanisms

Which of the following mechanisms increases DVT risk in pregnancy?

a. Reduced plasma volume

b. Increased t-PA activity

c. Compression of lower-limb veins by the uterus

d. Decreased clotting factor synthesis

e. Increased fibrinolysis

MCQ 9 — Arterial Thrombosis Etiology

A major cause of arterial thrombosis is:

a. Nephrotic syndrome

b. Atherosclerosis causing endothelial injury and turbulence

c. Superficial phlebitis

d. Dehydration

e. Hypotension alone

MCQ 10 — Cardiac Mural Thrombi

Which of the following promotes formation of cardiac mural thrombi?

a. Hyperventilation

b. Myocardial infarction causing dyskinetic myocardium

c. Hypothyroidism

d. Iron deficiency

e. High-altitude exposure

MCQ 11 — Embolic Targets of Arterial/Cardiac Thrombi

Arterial or cardiac mural thrombi commonly embolize to:

a. Skin and muscle

b. Brain, kidneys, and spleen

c. Lungs only

d. GI tract exclusively

e. Bones

STEP 2 — ANSWERS + SHORT EXPLANATIONS

MCQ 1 — b

Site determines outcome: venous → PE; arterial → infarction/occlusion.

MCQ 2 — c

Venous thrombi → pulmonary embolism, often fatal.

MCQ 3 — c

Arterial thrombi → occlude coronary/cerebral arteries → infarction.

MCQ 4 — c

Superficial thrombosis = pain, congestion, swelling, risk of varicose ulcers, but rarely embolizes.

MCQ 5 — c

DVTs above the knee → prone to embolize, 50% asymptomatic due to collateral flow.

MCQ 6 — e

Hyperthyroidism is NOT a risk factor. All others promote stasis or hypercoagulability.

MCQ 7 — b

Trousseau syndrome → tumor-released procoagulants, esp. adenocarcinomas.

MCQ 8 — c

Uterus compresses veins; pregnancy also causes hypercoagulability.

MCQ 9 — b

Atherosclerosis → endothelial injury + turbulence → arterial thrombosis.

MCQ 10 — b

MI → dyskinetic/akinetic region → stasis → mural thrombus.

MCQ 11 — b

High perfusion organs: brain, kidneys, spleen.

STEP 3 — HIGH-YIELD NOTES (EXAM-READY)

1. Why Thrombi Matter Clinically

• Thrombi cause:
• Obstruction of vessels.
• Emboli (detached fragments).
• The site is the key determinant of danger:
• Venous thrombi → pulmonary embolism (most dangerous outcome).
• Arterial thrombi → vessel occlusion → infarction (heart, brain).

2. Venous Thrombosis (Phlebothrombosis)

A. Superficial Venous Thrombi

• Most occur in saphenous veins, esp. in varicosities.
• Features:
• Pain, tenderness
• Local congestion
• Swelling
• Impaired venous outflow → predisposes skin to infections/varicose ulcers
• Rarely embolize

B. Deep Venous Thromboses (DVTs)

• Occur in popliteal, femoral, iliac veins.
• More serious because of high risk of embolization to lungs.
• Symptoms:
• May cause pain, edema
• BUT 50% asymptomatic due to collateral venous channels
• DVT is often first detected after pulmonary embolism.

Major risk factors

• Stasis:
• Bed rest
• Long flights
• Heart failure
• Immobilization (post-trauma, surgery, burns)
• Endothelial injury
• Trauma, surgery, burns
• Hypercoagulability
• Pregnancy (venous compression + hypercoagulability)
• Cancer (Trousseau syndrome)
• Postpartum state
• Age > 50 years

Trousseau Syndrome

• Migratory thrombophlebitis in cancers (e.g., pancreatic adenocarcinoma).
• Due to tumor-secreted procoagulants.

3. Arterial and Cardiac Thrombosis

Arterial Thrombosis

• Most commonly due to atherosclerosis:
• Damages endothelium
• Creates turbulence
• Promotes thrombosis
• Typically occlusive, causing:
• Myocardial infarction (coronary artery occlusion)
• Stroke (cerebral artery occlusion)

Cardiac Mural Thrombi

• Due to:
• Myocardial infarction → dyskinesia, stasis
• Atrial dilation + fibrillation → stasis (e.g., in rheumatic mitral stenosis)
• Endocardial injury (e.g., myocarditis)

Embolic Targets

• Because they arise from the left heart/aorta, they embolize to:
• Brain
• Kidneys
• Spleen
• These organs have high blood flow, making them prime sites for infarction.