RHEUMATIC HEART DISEASE (1)
RHEUMATIC HEART DISEASE (1)
RHEUMATIC HEART DISEASE (1)
• Risk factors
– Low standard of living
– Crowding
INTRODUCTION
• Rheumatic fever (RF) is an acute, immunologically mediated,
multisystem inflammatory disease classically occurring a few weeks
after group A streptococcal pharyngitis
• RHD is characterized principally by deforming fibrotic valvular disease,
particularly involving the mitral valve
• RHD is virtually the only cause of mitral stenosis.
• The incidence and mortality rate of RF and RHD have declined
remarkably in many parts of the world over the past century
• Reasons include improved sanitation, and rapid diagnosis and
treatment of streptococcal pharyngitis.
• Group A streptococcus pyogenes has a cell wall
composed of branched polymers which sometimes
contain "M proteins " that are highly antigenic
• During acute RF, focal inflammatory lesions are found in various tissues.
• Distinctive lesions in the heart—called Aschoff bodies—are composed of
foci of T lymphocytes, occasional plasma cells, and plump activated
macrophages called Anitschkow cells.
• Macrophages have abundant cytoplasm and central round to ovoid nuclei
(occasionally binucleate)
• Chromatin condenses into a central, slender, wavy ribbon ( “caterpillar
cells”).
• During acute RF, diffuse inflammation and Aschoff bodies may be found in
any of the three layers of the heart, resulting in pericarditis, myocarditis, or
endocarditis (pancarditis).
• Acute rheumatic fever can involve all the layers of the heart (acute
rheumatic pancarditis).
• Involvement of the endocardium is called endocarditis and can be of
two types – valvular or mural.
• Valvular endocarditis predominantly involves the left sided valves
ie. mitral and aortic with deposition of fibrin along the lines of the
closure or along the chordae tendinae.
• These deposits all organized to form warty vegetations called
verrucae which are firmly attached to the valve at the line of closure.
• The cardinal anatomic changes of the mitral valve in chronic RHD are
a. Leaflet thickening
b. Commissural fusion and shortening, and
c. Thickening and fusion of the tendinous cords
• The mitral valve is virtually always involved in chronic RHD
• It is affected in isolation in roughly two-thirds of cases, and along with
the aortic valve in another 25%.
• Tricuspid valve involvement is infrequent, and the pulmonary valve
is only rarely affected.
• In rheumatic mitral stenosis, calcification and fibrous bridging across
the valvular commissures create “fish mouth” stenoses
• With tight mitral stenosis, the left atrium progressively dilates and
may harbor mural thrombi that can embolize.
• Long-standing congestive changes in the lungs may induce pulmonary
vascular and parenchymal changes; over time, these can lead to right
ventricular hypertrophy
• The left ventricle is largely unaffected by isolated pure mitral stenosis.
• Microscopically, valves show organization of the acute inflammation,
with post-inflammatory neovascularization and transmural fibrosis
that obliterate the leaflet architecture.
• Aschoff bodies are rarely seen in surgical specimens or autopsy tissue
from patients with chronic RHD, because of the long intervals
between the initial insult and the development of the chronic
deformity.
CLINICAL FEATURES
• Acute RF typically appears 10 days to 6 weeks after a group A streptococcal
infection in about 3% of patients.
• It occurs most often in children between ages 5 and 15, but first attacks can
occur in middle to later life.
• 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.
• The predominant clinical manifestations are carditis and arthritis, the latter more
common in adults than in children.
Clinical Features
• Anti-DNAse B
• Anti-hyaluronidase test
Laboratory Findings
• ESR : 82 mm at the end of 1 hr
• ASLO titre : positive up to 800 IU /ml
• CRP : 30 IU / L
• On Examination: Patient has pericardial friction rub, tachycardia and
arrhythmias
1.Interpret the results and give your diagnosis
2. Mention the criteria to make the above diagnosis
CHART- 15