Valulvar heart disease Flashcards
What are cardiac valves
Non-return valves
What are the two main types of valvular disease?
- Valvular stenosis: narrowing of the valve orifice limits the quantity of blood passing through the valve.
- Valvular incompetence: failure of the non-return function of the valve leads to VALVULAR REGURGITATION
These can lead to reduction in cardiac output and infection (infective endocarditis)
What are the types of left heart valvular disease?
Mitral stenosis
Mitral regurgitation
Aortic stenosis
Aortic regurgitation
What is valve stenosis and what are the causes?
Thickening of the valve leaflets with calcification and closure of the commisures. (narrowing of the leaflets)
Causes:
- Degenerative stenosis associated with age related calcification
- Rheumatic heart disease (endemic in developing world)
- endocarditis
What are the complications of valvular disease?
Heart failure
Atrial Fibrillation
Infective endocarditis
What are the causes of mitral regurgitation?
Rheumatic heart disease (Developing countries)
Bacterial endocarditis
Mitral valve prolapse (floppy mitral valve)- 2-5% UK
IHD resulting in rupture of papillary muscle/ chordae tendinae
Cardiomyopathy
What are the causes of regurgitation?
Valvular incompetence due to: Rheumatic Heart disease Hyertension Syphilis Marfan’s syndrome Ehler’s-Danlos syndrome Osteogensis imperfecta Idiopathic aortic root dilatation Endocarditis
What is Marfan syndrome?
A connective tissue disorder.
Can cause high palate, make you look like the weird creepy guy from ghost.
What is rheumatic heart disease?
A consequence of acute rheumatic fever, a condition which occurs 2-3 wks after a group A streptococcal infection (throat).
Age group- 5 to 15 yrs.
Acute rheumatic fever is associated with poor nutrition and overcrowding.
10 – 15% of those who have suffered an episode of rheumatic fever will develop chronic scarring of the mitral valve cusps over a period of 40 – 50 years.
This scarring process thickens the valve cusps and fuses the commisures of the cusps leading to stenosis of the valve.
What’s an Aschoff body?
The histological hallmark of rheumatic fever.
What is infective endocarditis?
IE is an acute or chronic disease resulting 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 or coarctation of the aorta.
Classified into:
Acute: destructive infection, frequently of a previously normal heart valve with a highly virulent organism (S. aureus)
Subacute: insiduous disease, infection of a previously abnormal valve with organisms of low virulence (S. viridans).
What’s the pathology of infective endocarditis?
The lesions of Infective Endocarditis are known as vegetations which are grape-like nodular masses composed of bacterial colonies and thrombotic debris, and are adherent to the cusps of the valve.
95% of Infective Endocarditis occurs in the left sided valves, the Mitral and Aortic valves and most cases occur in previously damaged valves.
• Vegetation formation — The endothelial lining of the heart and its valves is normally resistant to infection with bacteria and fungi.
• ●The initial step in the establishment of a vegetation is endocardial injury, followed by focal adherence of platelets and fibrin.
• ●The initially sterile platelet-fibrin nidus becomes secondarily infected by microorganisms circulating in the blood, either from a distant source of focal infection, or as a result of transient bacteremia from a mucosal or skin source