Valvular Diseases Flashcards
What are causes of stenosis?
- Post inflammatory scarring
- Calcification
- Congenital
What are causes of insufficiency?
- Post inflammatory scarring
- Developmental (ie. marfans caused by mutation in fibrillin)
- Degenerative (myxomatous degeneration of mitral valve)
- Infectious
Can stenosis and insufficiency co-exist?
yes
Which are side of heart are valves more affected?
left
What types of valves are at higher risk of damage?
- Congenital bicuspid aortic valve
- Valves damaged by RHD
- Prosthetic Valves
Risk factor for acceleration of aortic valve calcification?
Congenital bicuspid aortic valves
What does aortic valve calcification result in?
aortic stenosis
Pathogenesis of aortic valve calcification?
age associated degeneration
Who gets mitral valve prolapse commonly? Ratio?
Women. 7:1 F:M ratio
What is the pathogenesis of mitral valve prolapse?
Usually unknown, associated with Marfan (Fibrillin-1 mutation)
Characteristics of mitral valve prolapse?
- Ballooning of valvular cusps with affected leaflets thickened and rubbery
- Myxoid degeneration of valve leaflets
What is the end result of mitral valve prolapse?
Mitral Regurg
Pathogenesis of RHD
Immune response to Gp A streptococcal antigens that cross react with host proteins
How to diagnose RHD?
JONES criteria - Joint, Myocarditis, Nodule, Erythema, Syndenham Chorea;
Minor: CSR, ERP, Arthralgia, Fever,
Diagnosis: Antistreptolysin O titre OR 2 major OR 1 major 2 minor
Morphology of Acute RHD?
- pancarditis
- aschoff bodies
- t cells
- plasma cells
- aschoff giant cells
- caterpillar cells (activated macrophages) - verrucae
Morphology of Chronic RHD?
- Inflammation, Fibrosis, Damage to Valves
- Always involve mitral valve with a smaller proportion the aortic valve
- Tricuspid and pulmonary valve involvement infrequent
- leads to stenosis or regurg
Pt with chronic RHD predisposed to which 3 diseases?
- Infective endocarditis
- Thromboembolism
- Arrythmias
Pathogenesis of Infective Endocarditis?
- Microbial infection of cardiac valves or endocardium = formation of vegetations = tissue destruction
Percentage of IE cases with a) mitral valve b) aortic valve c) tricuspid valve d) prosthesis e) Congenital Heart Diseases involvement
a) 25-30%
b) 25-35%
c). 10%
d) 10%
e) 10%
Common pts that get IE?
- IV drug abusers
- Open Heart Surgery
- Septicaemia pt
When might one get subacute IE?
- Insidious infection of abnormal heart valves (Congenital defects, prosthetic)
- Organisms of low pathogenicity derived from normal commensals of skin, mouth and gut
Organisms implicated in a) subacute IE, b) acute IE c) prosthetic valve IE d) other bacteria e) other organisms
a) step. viridans
b) s. aureus
c) s. epidermidis
d) enterococci, HACEK
e) fungi
What can predispose one to IE?
- Abnormal Valves
- Micro-organism seeding into blood
- dental or surgical procedure
- contaminated needle shared by IV drug users
- breaks in epithelial barriers of the gut, oral cavity, skin
Complications of IE?
Local
- valve rupture
- myocardial ring abscess
- suppurative pericarditis
distant
- septic emboli
- immune complex
- anemia of chronic disease
- splenomegaly
