1. VALVULAR HEART DISEASE

2. Learning objectives
Describe the etiology and clinical symptoms of acute rheumatic fever.
Describe the pathology and natural history of acute rheumatic fever and rheumatic heart disease.
Describe an Aschoff body.
Describe which parts of the heart are affected in acute rheumatic fever.
Describe the long-term consequences of rheumatic fever.
Describe the pathology and natural history of chronic rheumatic heart disease, and know which valves are most often involved.
Describe the pathology of postrheumatic mitral stenosis.
Enlist the components of vegetation.

3. Rheumatic fever and Rheumatic heart disease

4. Rheumatic fever
Rheumatic fever is an acute immunologically mediated multisystem inflammatory disease that occurs a few weeks following an episode of group A streptococcal pharyngitis.
Acute rheumatic carditis, during active phase
May progress to Chronic rheumatic heart disease.

5. Etiopathogenesis
Acute rheumatic fever is a hypersensitivity reaction induced by group A streptococci.
Antibodies against M proteins of certain strains of streptococci cross react with antigens in heart, joints and other tissues.
Genetic susceptibility is suggested
Autoimmune response to self antigens also suggested.
Chronic sequelae are a result of progressive fibrosis (healing process) and blood turbulance in valvular areas

6. Pathogenesis CROSS REACTIONS Fibrinous Aschoff body, pericarditis
myocardium
vegetations

7. Morphology ACUTE RH. FEVER-- Pancarditis
Pericarditis- serofibrinous/ Bread and butter type
Myocarditis  Aschoff bodies
Endocarditis 
Verrucous vegetations (1-2mm) at lines of closure of valves
Fibrinoid necrosis along cusps and teninous cords
MacCallum plaques in left atrium (Sub endocardial thickenings due to regurgitant jets)

8. vegetations
Aschoff body,
myocardium
Fibrinous
pericarditis

9. Carditis
Aschoff bodies
Aschoff/ Anitschow cells
Aschoff giant cell

10. Chronic disease rheumatic aortic stenosis rheumatic mitral valve,
With fused commisures
rheumatic mitral valve,

11. Morphology of chronic RHD
Mitral valve is most often affected with rheumatic heart disease, followed by mitral and aortic together, then aortic alone, then mitral, aortic, and tricuspid together.
Mitral stenosis (99% cases)
Fishmouth/ buttonhole stenosis
Microscopy
Fibrosis/ scarring
Neovascularization

12. Mitral valve as seen from above in the left atrium.
Typical "fish mouth" shape with chronic rheumatic scarring.
Mitral valve is most often affected with rheumatic heart disease, followed by mitral and aortic together, then aortic alone, then mitral, aortic, and tricuspid together.

13. Clinical features of ARF
The major clinical manifestations of ARF:
migratory polyarthritis
carditis,
subcutaneous nodules,
erythema marginatum, and
Sydenham chorea.
Minor manifestations of ARF:
Fever, arthralgias, Increased blood levels of acute phase reactants etc.

14. DIAGNOSIS Jones criteria:
Evidence of preceding group A strept. Infection
Presence of two major or one major and two minor manifestations

15. Clinical features of ARF
Age: 5-15 but may be in adults
Time: 10 days to 6wks after pharyngitis
3% of pts effected
Prognosis of 1st attack good.

16. Clinical features of chronic rheumatic carditis
Valvular disease and its sequelae (yrs later)
Murmurs
Cardiac hypertrophy, dilatation, heart failure
Arrythmias esp Atrial fibrillation
Thromboembolic complications
Infective endocarditis

17. In the dilated atrium with a stenotic mitral valve, the blood stagnates. Hence, stasis is a factor in thrombogenesis..

18. Infective endocarditis

19. Infection of heart valve or mural endocardium by a microbe leading to formation of bulky friable vegetations and destruction of underlying tissue.
Vegetations are composed of thrombotic debris and organisms

20. Classification Acute Subacute Virulent organism Normal valve
Necrotizing ulcerative, invasive infection
Maybe fatal
Subacute
Less virulent organism
Damaged valve
Treatable with antibiotics

21. Etiopathogenesis ORGANISMS
Most cases are bacterial although chlamydiae and ricketia also implicated
Damaged valves: Strept. Viridans (50-60%)
Normal/ damaged: Staph. Aureus (10-20%)
I/V drug abusers: Staph. Aureus Prosthetic valves: Staph epidermidis
Others are enterococci, HACEK
Culture negative: 10%

22. Etiopathogenesis PREDISPOSED VALVES RHD (previously)
Myxomatous mitral valve
Degenerative calcific valvular stenosis
Prosthetic valves
HOST FACTORS
Immunodeficiency, immunosupression
Malignancy
Diabetes
Alcohol
I/V drug abuse

23. Clinical features
Osler’s nodes
Splinter hgs
Petechiae
Janeway lesions

24. Diagnosis

26. morphology
The more virulent bacteria causing the acute bacterial form of infective endocarditis can lead to serious destruction, as shown here in the aortic valve. Irregular reddish tan vegetations overlie valve cusps that are being destroyed. Portions of the vegetation can break off and become septic emboli.

27. Here is a valve with infective endocarditis
Here is a valve with infective endocarditis. The blue bacterial colonies on the lower left are extending into the pink connective tissue of the valve. Valves are relatively avascular, so high dose antibiotic therapy is needed to eradicate the infection.