Other cardiovascular pathology (cardiovascular system 2) Flashcards
Valvular Heart disease
What is stenosis?
What is incompetence (regurgitation)?
What are the problems with valve regurgitation?
What is functional regurgitation?
STENOSIS - failure of the valve to open completely -> impedes the forward flow of blood
INCOMPETENCE (REGURGITATION) - failure of the valve to close completely allows the reverse flow of blood PURE OR MIXED, SINGLE OR MULTIPLE VALVES
FUNCTIONAL REGURGITATION - valve becomes incompetent due to dilation of a ventricle
Clinical consequences of valvular heart disease depend on?
Rheumatic mitral stenosis can lead to?
Clinical consequences depend on: Which valve, degree of impairment, rate of its development, rate and quality of compensatory mechanisms
physiologically unimportant -> severe and rapidly fatal
rheumatic mitral stenosis -> acute aortic incompetence, secondary to destruction of valve cusp from infection
Valvular incompetence
Happens due to?
Intrinsic disease of the valve cusps or damage to or distortion of the supporting structures - aorta, mitral valve annulus, tendinous cords, papillary muscles, ventricular free wall
+/- underlying valve abnormality. ACUTE OR CHRONIC
Valvular stenosis occurs almost always due to?
Is it usually chronic or acute?
Almost ALWAYS has an underlying VALVE ABNORMALITY
Usually CHRONIC
VALVULAR CALCIFICATION
Where is it commonly seen in?
What problems does it cause?
Calcific aortic stenosis • Calcification of a congenitally bicuspid aortic valve • Mitral annular calcification
The heart valves are subjected to high repetitive mechanical stresses especially at hinge points of cusp / leaflet 1. 40 million cardiac cycles / year 2. Substantial tissue deformation at each cycle 3. Transvavlular pressure gradients - Aortic 120mmHg Mitral 80mmHg CUMULATIVE DAMAGE COMPLICATED BY DYSTROPHIC CALCIFICATION
Calcific aortic stenosis?
What age is it clinically apparent?
Calcification of bicuspid aortic valves occur at what age?
What are the common causes of the following diseases:
1) Mitral stenosis
2) Mitral Incompetence
3) Aortic stenosis
4) Aortic incompetence
MITRAL STENOSIS - Rheumatic heart disease
MITRAL INCOMPETENCE - Floppy mitral valve (myxomatous degeneration) (mitral valve prolapse)
AORTIC STENOSIS - Calcification of normal and congenitally bicuspid aortic valves
AORTIC INCOMPETENCE - Dilation of ascending aorta related to hypertension and age
FLOPPY MITRAL VALVE
- Common
- Most common form of valvular heart disease in industrialised world
- One or both mitral leaflets enlarged, hooded, redundant
-> prolapse back into LA during systole
- Usually incidental finding on examination - mitral valve prolapse
- Very rarely -> sudden death
RHEUMATIC FEVER
What is it?
It occurs few weeks after what type of infection?
what are the features of the disease?
Acute rhematoid heart disease can lead to what?
- Acute immunologically mediated multisystem inflammatory disease
- Occurs a few weeks after group A B-haemolytic streptococcal pharyngitis •Thought to be a hypersensitivity reaction induced by group A streptococci
- Features:
- Migratory polyarthritis of large joints •Carditis •Subcutaneous nodules •Skin rash •Sydenham chorea - neurological disorder (purposeless movements
Acute rheumatic heart disease -> pancarditis
- Endocardium -> Vegetations
- Myocardium Inflammatory -> foci with ASCHOFF BODIES
- Pericardium -> Pericarditis
- Reactivation with subsequent pharyngeal infections -> cumulative damage
What are the major and minor criteria of the Johnes criteria which is used for diagnosis of rheumatoid disease?
Chronic rheumatic heart disease - what is the most important consequence
Is it the most common cause of mitral stenosis?
The most important consequence of rheumatic fever is
CHRONIC RHEUMATIC HEART DISEASE
Characterised by
• deforming fibrotic valvular disease (especially mitral stenosis) FISH MOUTH / BUTTON-HOLE STENOSES
leaflet thickening, commissural fusion and shortening, thickening and fusion of the chordae tendinae. can -> permanent dysfunction
- most frequent cause of mitral stenosis (99% of cases)
- End stage of organisation of acute inflammatory damage
Infective endocarditis
What is it
Is it mostly a virus or bacterial?
What predisposes it?
What is the difference between acute and subacute infective endocarditis
Serious infection • Colonisation / invasion of heart valves • Formation of friable bulky vegetations - composed of thrombotic debris and organsims • Often underlying tissue destrudtion • Most cases are BACTERIAL
Things which predispose it
Abnormal valve: Floppy mitral valve, degenerative calcific valvular stenosis, bicuspid aortic valve, artificial valve (vascular graft).
Host factors: Immunosuppresion - neutropaenia immunodeficiency therapeutic, diabetes, alcohol, intravenous drug abuse
What organism is commonly involved in infective endocarditis?
What organism is seen in infective endocarditis in IV drug users?
What infection is seen in prosthetic valves?
Morphology of infective endocarditis -> which valve is commonly affected. Which valve commonly affects IV drug users?
a-haemolytic streptococcus abnormal valve (50-60%) subacute
Staph aureus (skin) high virulence normal valve IV drug users
Mouth commensals most of rest
Staph epidermidis prosthetic valves
SEEDING OF BLOOD WITH MICROBES (BACTERAEMIA) Dental or surgical procedure, dirty needle, trivial injury
PROPHYLACTIC ANTIBIOTICS IN THOSE AT RISK
Aortic and mitral valve most commonly affected
Tricuspid valve in IV drug users
Bulky friable vegetations, May involve more than one valve
Complications of infective endocarditis?
Non bacterial thrombotic endocarditis.
When does it normally occur?