2. Acute , immunologically mediated, multisystem
inflammatory disease.
Occurs 10 days to 6 weeks after an episode of
group A streptococcal pharyngitis.
Affects usually children (5-15 yrs) but 20% cases
can be seen in adults.
Active phase of RF may progress to chronic
RHD.
RF does not occur after a streptococcal inf at
other sites eg skin.
3. Is an important public health problem in
poor socioeconomic localities
Incidence has < due to better living
standards, rapid diagnosis, good drug
therapy & unexplained < in virulence of gp
A streptococci
5. Morphology
HEART LESIONS:
- Acute RF: characterized by distinctive lesions
called ASCHOFF BODIES in the myocardial
interstitium.
- They are circumscribed lesions consisting of a
central focus of necrotic,swollen eosinophilic
collagen surrounded by T-lymphocytes,
occasional plasma cells & plump macrophages
called Anitschkow cells (abundant cytoplasm
central round to ovoid nuclei with chromatin
disposed in a central, slender, wavy ribbon).
- also called caterpillar cells - pathognomonic for
RF.
- some large macrophages become multinucleated
Aschoff Giant Cells.
6. During acute RF, diffuse inflammation &
Aschoff bodies may be found in all 3
layers of heart (PANCARDITIS)
PERICARDIAL LESIONS:
Fibrinous or serofibrinous pericardial
exudate called “bread & butter”
pericarditis.
This generally resolves without any
sequelae.
7. MYOCARDIAL LESIONS:
- Myocarditis
Scattered Aschoff bodies within the interstitial
connective tissue
ENDOCARDIAL LESIONS:
Simultaneous involvement of endocardium &
left sided cardiac valves by inflammatory foci
causes fibrinoid necrosis of cusps or chordae
tendinae.
8. Small 1-2 mm vegetations called “verruca”
situated along the line of closure of the valves.
They are irregular & wart-like
Cause little disturbance in cardiac function
Formed due to precipitation of fibrin & collagen
degeneration at sites of closure
Left atrium shows irregular, subendocardial
lesions called MacCallum plaques
9. PATHOGENESIS
Acute RF is a hypersensitivity reaction
caused by gp A Streptococci
Antibodies against M protein of certain
strains of streptococci cross-react with
glycoprotein antigens in the heart, joints &
other tissues
Streptococcal infection evokes an
autoimmune response against self-
antigens
Genetic suseptibility also plays a major
role in pathogenesis of this disease
10. Group A streptococci elaborate the
cytolytic toxins streptolysins S and O.
Streptolysin O induces persistently
high antibody titers that provide a useful
marker of group A streptococcal
infection and its nonsuppurative
complications (ASO Ab test).
11. Rheumatogenic strains often are
encapsulated mucoid strains rich in M
proteins and resistant to phagocytosis.
The presence of the M protein in the cell
wall is the most important virulence factor for
group A streptococcal infection in humans.
12. CHRONIC RHD
Characterized by organization of acute
inflammation & fibrosis
Permanent valvular deformity (esp mitral valve)
due to retraction & thickening of leaflets
Mitral & tricuspid valves show leaflet thickening,
commissural fusion, shortening, thickening &
fusion of tendinous cords
13. VALVULAR LESIONS of CH.RHD
Mitral valve alone is affected in 65-70%
cases of RHD.
RHD is responsible for 99% cases of
mitral stenosis
Concomitant involvement of mitral & aortic
valve is seen in 25% cases
Less severe damage may also occur in
the tricuspid & pulmonary valves
14. Fibrous bridging & calcification across
valvular commissures creates “fish
mouth” or “buttonhole” stenosis.
Mitral stenosis causes progressive left
atrial dilatation, harbouring a mural
thrombus in its appendage or along its
wall.
Lungs show congestive changes
ultimately leading to rt ventricular
hypertrophy.
Left ventricle is essentially normal with
isolated mitral stenosis
15. Microscopy (RHD)
Diffuse & dense fibrosis.
Neovascularization of valves.
Aschoff bodies are replaced by fibrous
scar therefore not seen in autopsy
specimens of ch CHD
17. Major Criteria (JONES)
1. Migratory polyarthritis of large joints
2. Carditis
3. Subcutaneous nodules
4. Erythema marginatum of skin
5. Syndenham chorea
18. JONES (Major Criteria)
J =Joints (migratory polyarthritis).
O=(imagine heart shape) Carditis.
N=Nodules (s/c nodules), painless collections of
collagen fibres on back of wrists, front of knees.
E= Erythema marginatum (long lasting rash that
begins on trunk or arms.)
S= Syndenhams chorea ( rapid purposeless
movements of limbs & face.)
22. Clinical features: arthritis & carditis
- arthritis is more common in adults than
children
-begins as migratory polyarthritis
accompanied with fever
One large joint is involved after another
becomes painful & swollen for some days
Subsides spontaneously
Leaves no residual deformity
23. Carditis: pancarditis
Pericardial friction rubs
Weak heart sounds
Tachycardia & arrhythmias
New heart murmurs.
other clinical features include epistaxis &
abdominal pain.
24. Myocarditis may cause cardiac dilatation
leading to mitral valve insufficiency or
even heart failure.
PROGNOSIS
In cases of primary attack is excellent with
only 1% cases dying from fulminant RF
25. COMPLICATIONS
RECURRENCES are liable to occur after
each subsequent pharnygeal attack with
similar clinical manifestations.
CARDITIS TENDS TO MORE SEVERE in
recurrent episodes.
EMBOLIZATION from mural thrombi
within atria or their appendages.
INFECTIVE ENDOCARDITIS
superimposed on deformed valves.
26. Ch rheumatic carditis does not cause
clinical manifestations for years or even
decades after the initial episode of RF
CARDIAC MURMURS
CARDIAC HYPERTROPHY &
DILATATION
HEART FAILURE
ARRHYTHMIAS LIKE ATRIAL
FIBRILLATION
27. Treatment
Surgical repair by incising the diseased
mitral stenotic valve commissures &
replacement by prosthetic devices has
greatly improved the outcome of this
disease.
31. Ch.rheumatic valvulitis affecting the mitral valve & dev due to organization &
fibrosis of ac endocardial inflammation. Note the shortened & thickened
chordae tendinae
43. ACUTE RH.HEART DISEASE
Fig 5-6. Rheumatic Heart Disease: A: In acute rheumatic heart disease. There is necrosis and
an associated inflammatory reaction in the myocardial interstitium.
44. RH.HEART DISEASE
Fig 5-6. Rheumatic Heart Disease: B: The Aschoff body is pathognomonic for rheumatic
heart disease and is composed of a necrotic focus infiltrated by mononuclear and
multinucleated giant cells, Anitschkow cells.
45. RH.HEART DISEASE
Fig. 5-6. Rheumatic Heart Disease: C: Healed rheumatic valvulitis is characterized by blood vessels
proliferation and an associated inflammatory reaction.
