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Question 1

What are the possible causes of valvular insufficiency

Answer 1

1. Post inflammatory scarring (Eg. rheumatic heart disease)
2. Developmental (Eg. in marfan’s syndrome → defective fibrin formation)
3. Degenerative (Eg. myxomatous degeneration of the mitral valve)
4. Infections (Acute inflammation, Eg. in syphillis and infective endocarditis)

Question 2

What type of valves predisposes an individual to valvular heart disease

Answer 2

Structurally abnormal valves:

1. Congenital bicuspid aortic valve
2. Valves damaged by rheumatic heart disease
3. Prosthetic valves

Question 3

What is aortic valve calcification

Answer 3

Age-associated degeneration, most common of all valvular abnormalities

Accelerated in congenitally bicuspid aortic valves

Results in aortic stenosis

Question 4

Pathogenesis of mitral valve prolapse

Answer 4

Cause: unclear, but some cases are linked with marfan syndrome (fibrillin-1 mutation)

1. Ballooning of the valvular cusps with the affected leaflets thickened and rubbery
2. Jelly-like myxoid degeneration of valve leaflets
3. Results in mitral regurgitation

Question 5

What is acute rheumatic heart disease

Answer 5

Inflammation occuring in all 3 layers of the heart (pancarditis)

Inflammation comprises “Aschoff bodies”

1. T lymphocytes
2. Plasma cells
3. Aschoff giant cells
4. Activated macrophage (anitschkow/caterpillar cell)

Question 6

What is chronic rheumatic heart disease

Answer 6

1. Cumulative damage caused by subsequent infections
2. Inflammation, fibrosis and damage to valves + fibrous thickening and fusion of the chordae tendineae
3. Stenosis and/or regurgitation
4. Predisposition to infective endocarditis, thromboembolism, arrhythmias

Question 7

What is infective endocarditis

Answer 7

Disease caused by microbial infection of the cardiac valves or endocardium → formation of vegetations (with bacteria inside) → tissue destruction

Question 8

What is acute infective endocarditis

Answer 8

• Normal heart valves involved
• Highly virulent pathogenic organisms directly invade the valve and cause rapid destruction
• Usually seen in IV drug addicts, open heart surgery and septicemia
• Can lead to the formation of myocardial ring abscesses which are necrotic

Question 9

What is the cause of rheumatic fever

Answer 9

Abnormal immune response to group A streptococcal pharyngitis

Question 10

Pathogenesis of rheumatic fever

Answer 10

Immune response (antibodies) to streptococcal antigens which cross-react with host proteins antigens on cardiac myocytes and with heart valve glycoproteins