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Flashcards in Valvular Heart Disease Deck (31)
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1
Q

What is valvular heart disease?

A

Functional deficiency of the heart valves

2
Q

How many cardiac valves and describe them?

A

4 valves:
2 atrioventricular valves allow blood flow from atrium to ventricle (Tricuspid on the right and mitral on the left)
2 outlet valves allow blood from ventricles to arteries (Pulmonary allows blood from the right ventricle into the pulmonay artery, Aortic allows blood from the left ventricle into the aorta)

3
Q

What type of valve are all the heart valves?

A

Non return valves

4
Q

What are the two types of valvular heart disease?

A
Valvular stenosis
Valvular incompetance (regurgitation)
5
Q

What is valvular stenosis?

A

Narrowing of the valve, limiting the quantity of blood passing through

6
Q

What is valvular incompetance?

A

Failure of the non return function of the valve leads to valvular regurgitation

7
Q

What are the consequences of valvular heart disease?

A

Decrease in cardiac output - poor function, exercise intolerance, left ventircular hypertrophy, left ventricular failure, sudden death
Infection - damaged vessels susceptible, infective endocarditis

8
Q

What are the 4 causes of left heart valvular disease?

A

Mitral Stenosis
Mitral Regurgitation
Aortic Stenosis
Aortic Regurgitation

9
Q

What is mitral stenosis?

A

Left heart valvular disease.
Narrowing of the mitral valve, thickening of the valve leaflets with calcification and closure of the commisures.
Complications: heart failure, atrial fibrillation, Infective endocarditis

10
Q

What causes mitral stenosis

A

Degenerative mitral stenosis associated with age related calcification
Rheumatic heart disease

11
Q

What is mitral regurgitation?

A

Left heart valvular disease.
A diseased valve fails to close properly and leaks.
Complications: heart failure, atrial fibrillation, endocarditis risk.

12
Q

What causes mitral regurgitation?

A

Rheumatic heart disease, bacterial endocariditis, mitral valve prolapse, ischaemic heart disease resulting in rupture of papillary muscle/chordae tendonae, cardiomyopathy,

13
Q

What is aortic stenosis?

A

Left heart valvular disease. Narrowing of the aortic valve.

Results in obstruction to the left ventricular flow.

14
Q

What causes aortic stenosis?

A

Congential bicuspid valve, degenerative calcification, rheumatic heart disease

15
Q

What is aortic regurgitation?

A

Left heart valvular disease.

Arises from valve dysfunction or incompetace or dilation of the aortic root.

16
Q

What causes aortic regurgitation?

A

rheumatic heart disease, hypertension, syphilis, marfans syndrome, ehlers - danlos syndrome, osteogenesis imperfecta, idiopathic aortic root dilation, endocarditis

17
Q

What are the 2 causes of right heart valvular disease?

A

Tricuspid stenosis - most commonly caused by rheumatic fever
Triscupid regurgitation - due to right ventricular enlargement which has been caused by rheumatic heart disease, congenital heart disease or endocarditis secondary to IV drug use/abuse.

18
Q

What is rheumatic heart disease?

A

Consequence of acute rheumatic fever which occurs 2 -3 weeks after group A streptococcal infection in the throat

19
Q

Complication of rheumatic heart disease?

A
Antibody cross reactivity which causes:
Heart - pericarditis, myocarditis, endocarditis
Joints - polyarthritis
Skin - nodules, skin rashes
Arteries - arteritis
20
Q

What % of children with acute rheumatic fever never fully recover?

A

95%

21
Q

What % of those who have suffered an episode of rheumatic fever will develop chronic scarring of mitral valve cusps?

A

10 - 15%

22
Q

What is the consequence of scarring on mitral valve cusps?

A

Scarring thickens the valve cusps and fuses the commissures of the cusps leading to valve stenosis

23
Q

What is infective endocarditis?

A

An acute or chronic disease from infection of a focal area of the endocardium. A heart valve is usually involved but the process may affect the mural endocardium of the atrium or ventricle, or a congenital defect such as a patent ductus arteriosus.

24
Q

Describe acute infective endocarditis?

A

Destructive infection of a previously normal heart valve with a highly virulent organism (e.g. S. aureus)

25
Q

Describe Subacute infective endocarditis?

A

Insidious disease, infection of a previously abnormal valve with organisms of low virulence (e.g. S. viridans)

26
Q

Where is the source of organisms for infective endocarditis?

A

Oropharynx - strep
Resp Tract
Skin - strep and candida
GI and urinary tract - strep faecalis

27
Q

What is the main organism for infective endocarditis?

A

Strep Viridans - 60%

28
Q

What are vegetations?

A

Lesions of infective endocarditis, composed of bacterial colonies and thrombotic debris.
They stick to the cusps of the valve

29
Q

Where does most infective endocarcitis occur?

A

95% occurs in left sided valves (mitral and aortic) and most cases occur in previously damaged valves.

30
Q

Describe vegetation formation?

A

1) Endocardial injury followed by a focal adherence of platelets and fibrin
2) Initially sterile platelet - fibrin area become secondarily infected by microorganisms circulating in the blood, either from a distant source or as a result of transient bacteraemia from mucosal / skin source.

31
Q

Consequences of medications linked to infective endocarditis?

A

Anticoagulants - bleeding risk
Calcium channel blockers - gingival hyperplasia
Beta blockers, ACE inhibitors, diuretics - oral drug reactions