“RHEUMATIC HEART
DISEASE”
DR KIRAN H S
YMC PATHOLOGY
RHEUMATIC FEVER (RF)

Definition

Etiopathogenesis

Morphological changes

Clinical featues

Complications
ETIOPATHOGENESIS
 Immune
 to
responses
group A streptococci,
 which
happen to cross-react with host
tissues
CD4+ T cells
produce
cytokines that
activate
macrophages
M proteins of
streptococci

antibodies against the M proteins of certain strains
of streptococci  cross-react with glycoprotein
antigens in the heart, joints, and other tissues.
 Evidence
supporting the concept

onset of symptoms 2 to 3 weeks after
infection and

the absence of streptococci from the lesions
THE CHRONIC
SEQUELAE
 result
from
progressive fibrosis due to both

healing of the acute inflammatory lesions and

the turbulence induced by ongoing valvular
deformities.
Rheumatic fever (RF) is an
acute,
immunologically mediated,
multisystem inflammatory disease
that occurs a few weeks following an
episode of group A streptococcal
pharyngitis
Rheumatic fever (RF) is an
acute,
immunologically mediated,
multisystem inflammatory disease
that occurs a few weeks following an
episode of group A streptococcal
pharyngitis
 Acute
rheumatic carditis

is a frequent manifestation during the active phase of
RF and

may progress over time to
 chronic
rheumatic heart disease (RHD)
MORPHOLOGY
ACUTE RF
 focal
inflammatory lesions are
found in various tissues.
 most

distinctive within the heart,
where they are called Aschoff bodies
Aschoff bodies
foci of swollen
eosinophilic collagen
 surrounded by
 lymphocytes
(primarily T cells),
 occasional plasma
cells, and
 plump macrophages
called Anitschkow
cells
(pathognomonic for
RF).

Anitschkow cells
macrophages
 abundant cytoplasm


central round-to-ovoid
nuclei
chromatin is disposed in a
central, slender, wavy
ribbon
( “caterpillar cells” ),


may become
multinucleated


“caterpillar” shape
longitudinally.
“owl-eye” appearance
in cross-section
PANCARDITIS

During acute RF
 diffuse inflammation and Aschoff bodies
 may be found in
 any of the three layers of the heart, causing
pericarditis,
 myocarditis, or
 endocarditis

PERICARDITIS




In the pericardium, the
inflammation is accompanied by
a
fibrinous or serofibrinous
pericardial exudate, described
as
a "bread-and-butter"
pericarditis,
generally resolves without
sequelae.
MYOCARDITIS



takes the form of
scattered Aschoff bodies within the interstitial
connective tissue,
often perivascular
INFLAMMATION OF THE ENDOCARDIUM
AND THE LEFT-SIDED VALVES
Typically results in
 fibrinoid necrosis
 within the cusps
 or
 along the tendinous cords.

Overlying these necrotic foci are
 small (1- to 2-mm) vegetations,
verrucae

called

along the lines of closure.


These irregular, warty projections probably
arise from
 the precipitation of fibrin at sites of
EROSION,
 related to
 underlying inflammation and
 collagen degeneration
cause little disturbance in cardiac function
OTHER VEGETATIVE VALVE DISEASES




Regurgitant jets
may induce irregular
Subendocardial
thickenings called
MacCallum plaques,
usually in the left
atrium.
CHRONIC RHD-MORPHOLOGY


characterized by
 organization of the acute inflammation and
 subsequent fibrosis.
In particular,
 the valvular leaflets become
 thickened and
 retracted,
 causing permanent deformity

cardinal anatomic
changes of the mitral (or
tricuspid) valve are

leaflet thickening,

commissural fusion and
shortening, and

thickening and fusion of
the tendinous cords

Fibrous bridging across the valvular commissures and
calcification create “fish mouth” or “buttonhole”
stenoses
MICROSCOPY- CHRONIC RHD

there is diffuse fibrosis and

often neovascularization that



obliterate the originally layered and avascular
leaflet architecture.
Aschoff bodies are replaced by fibrous scar
Fibrosis resulting from healed inflammation
outside the valves is usually of no consequence
RHD


characterized principally by deforming fibrotic
valvular disease
particularly mitral stenosis,
 of which it is virtually the only cause
mitral valve alone  65% to 70% of cases
 mitral and aortic  25%


Frequency
 Mitral > aortic > tricuspid > pulmonic (only rarely
affected)
left atrium
progressively
dilate
right
ventricular
hypertrophy
pulmonary
vascular and
parenchymal
changes
left ventricle is
largely
unaffected by
isolated pure
mitral stenosis.
CLINICAL FEATURES

Major manifestations
(1) migratory polyarthritis of the large joints
(2) pancarditis
(3) subcutaneous nodules
(4) erythema marginatum of the skin, and
(5) Sydenham chorea, a neurologic disorder with
involuntary rapid, purposeless movements.
MINOR MANIFESTATIONS

nonspecific signs and symptoms
 Fever
 Arthralgia
 elevated blood levels of acute-phase reactants
DIAGNOSIS

established by the so-called
Jones criteria



evidence of a preceding group A streptococcal
infection, with the presence of
two of the major manifestations
or
one major and two minor manifestations
ACUTE RF


typically appears
10 days to 6 weeks after an episode of
pharyngitis caused by group A streptococci

in about 3% of infected patients.

most often in children between ages 5 and 15,

but first attacks can occur in middle to later life.



Although pharyngeal cultures for streptococci
are negative by the time the illness begins,
antibodies to one or more streptococcal enzymes,
such as streptolysin O and DNase B, can be
detected in the sera of most patients with RF
Evidence of a preceding group A streptococcal
infection
CLINICAL FEATURES & COMPLICATIONS
RELATED TO ACUTE CARDITIS
pericardial friction rubs
 weak heart sounds
 tachycardia
 arrhythmias.



Myocarditis may cause cardiac dilation can
evolve to functional mitral valve insufficiency
or even heart failure.
Approximately 1% of patients die from fulminant
RF.
ARTHRITIS


typically begins with migratory polyarthritis
(accompanied by fever) in which
one large joint after another becomes painful and
swollen for a period of days and

then subsides spontaneously,

leaving no residual disability.




After an initial attack
there is increased vulnerability to reactivation
of the disease with subsequent pharyngeal
infections, and
the same manifestations are likely to appear
with each recurrent attack.
Damage to the valves is cumulative
CHRONIC


RHD
Turbulence induced by ongoing valvular
deformities  additional fibrosis.
Clinical manifestations
 appear years or even decades after the initial
episode of RF and

depend on which cardiac valves are involved.

Cardiac murmurs

Cardiac hypertrophy and dilation

Heart failure



Arrhythmias
 (particularly atrial fibrillation in the setting of
mitral stenosis)
Thromboembolic complications
Infective endocarditis.
Bacterial endocarditis
 follows episodes of bacteremia

in persons with risk factors (e.g., during dental
procedures).

The scarred valves of rheumatic heart disease
provide an attractive environment for
bacteria that would bypass a normal valve.
Mural thrombi
 form in atrial or ventricular chambers
 in 40% of patients with rheumatic valvular
disease.
 They give rise to thromboemboli,
 which can produce infarcts in various organs.
Congestive heart failure
 may complicate rheumatic disease
 of both mitral and aortic valves.
 cardiac hypertrophy and dilation

Arrhythmias
 particularly atrial fibrillation
 in the setting of mitral stenosis
THE INCIDENCE
RF AND RHD




AND MORTALITY RATE OF
Have declined remarkably in many parts of the world over the past
century
Result of
 improved socioeconomic conditions and
 rapid diagnosis and treatment of streptococcal pharyngitis.
RHD remains an important public health problem in
 developing countries
 in many crowded, economically depressed urban areas in the
Western world
 affecting an estimated 15 million people.
Rheumatic fever only rarely follows infections by streptococci at
other sites, such as the skin.

Definition

Etiopathogenesis

Morphological changes

Clinical featues

Complications