Orris

Rheumatic hear disease

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Quick answer

Rheumatic heart disease (RHD) is permanent damage to heart valves caused by one or more episodes of acute rheumatic fever, an autoimmune reaction that can occur after an untreated or inadequately treated group A streptococcal throat infection.

What happens

The immune response inflames the heart, especially the valves. Repeated inflammation causes scarring, thickening, and narrowing or leakage of valves.
  • Mitral valve is affected most often
  • Aortic valve may also be involved
  • Valve lesions can cause mitral stenosis, mitral regurgitation, aortic regurgitation, or combined disease

Symptoms

Early disease may cause no symptoms. Later features include:
  • Breathlessness, especially on exertion or lying flat
  • Fatigue and reduced exercise tolerance
  • Palpitations, often due to atrial fibrillation
  • Leg swelling
  • Chest discomfort
  • Coughing blood in severe mitral stenosis
  • Stroke risk from atrial fibrillation or clots in the enlarged left atrium

Diagnosis

  • History of rheumatic fever or recurrent sore throats can help
  • Heart murmur on examination
  • Echocardiography confirms valve damage and its severity
  • ECG and chest X-ray may show rhythm abnormalities or heart enlargement

Treatment and prevention

  • Treat streptococcal throat infection promptly with appropriate antibiotics.
  • People with prior rheumatic fever often need long-term secondary prophylaxis, commonly regular penicillin, to prevent recurrence.
  • Heart failure medicines, rhythm control, and anticoagulation may be needed depending on the valve lesion and atrial fibrillation.
  • Severe valve disease may require balloon mitral valvotomy, valve repair, or valve replacement.
Seek urgent care for sudden severe breathlessness, coughing blood, fainting, stroke symptoms, or fast irregular palpitations.

RHD Pathophysiology

Rheumatic heart disease (RHD) is permanent damage to heart valves caused by one or more episodes of acute rheumatic fever, an autoimmune reaction that can occur after an untreated or inadequately treated group A streptococcal throat infection.

What happens

The immune response inflames the heart, especially the valves. Repeated inflammation causes scarring, thickening, and narrowing or leakage of valves.
  • Mitral valve is affected most often
  • Aortic valve may also be involved
  • Valve lesions can cause mitral stenosis, mitral regurgitation, aortic regurgitation, or combined disease

Symptoms

Early disease may cause no symptoms. Later features include:
  • Breathlessness, especially on exertion or lying flat
  • Fatigue and reduced exercise tolerance
  • Palpitations, often due to atrial fibrillation
  • Leg swelling
  • Chest discomfort
  • Coughing blood in severe mitral stenosis
  • Stroke risk from atrial fibrillation or clots in the enlarged left atrium

Diagnosis

  • History of rheumatic fever or recurrent sore throats can help
  • Heart murmur on examination
  • Echocardiography confirms valve damage and its severity
  • ECG and chest X-ray may show rhythm abnormalities or heart enlargement

Treatment and prevention

  • Treat streptococcal throat infection promptly with appropriate antibiotics.
  • People with prior rheumatic fever often need long-term secondary prophylaxis, commonly regular penicillin, to prevent recurrence.
  • Heart failure medicines, rhythm control, and anticoagulation may be needed depending on the valve lesion and atrial fibrillation.
  • Severe valve disease may require balloon mitral valvotomy, valve repair, or valve replacement.
Seek urgent care for sudden severe breathlessness, coughing blood, fainting, stroke symptoms, or fast irregular palpitations.
Reading File

Quick answer

Pathophysiology of Rheumatic Heart Disease (RHD)

RHD is the chronic valvular damage that follows acute rheumatic fever (ARF) after an untreated group A beta-hemolytic Streptococcus throat infection.

1. Trigger: streptococcal pharyngitis

About 2 to 4 weeks after streptococcal sore throat, some susceptible individuals develop an abnormal immune response. The bacteria do not directly infect the heart valves.

2. Molecular mimicry

Streptococcal antigens, especially M protein, resemble proteins in human tissues, including cardiac myosin and valve tissue.
  • The body produces antibodies and activated T cells against streptococci.
  • These immune cells cross-react with the patient’s own heart tissue.
  • This autoimmune cross-reaction is called molecular mimicry.

3. Acute rheumatic carditis

Inflammation may involve all three layers of the heart, called pancarditis:
  • Endocarditis/valvulitis: swelling and inflammation of valve leaflets and chordae
  • Myocarditis: myocardial inflammation may impair cardiac function
  • Pericarditis: fibrinous inflammation can cause chest pain and a pericardial rub
Typical early valve lesions include small sterile vegetations along the line of valve closure. Acute inflammation commonly causes mitral regurgitation, sometimes with aortic regurgitation.

4. Aschoff bodies

The characteristic histologic lesion of rheumatic carditis is the Aschoff body, a granuloma-like inflammatory focus in the myocardium.
It contains:
  • T lymphocytes
  • Plasma cells
  • Macrophages, including distinctive Anitschkow cells with caterpillar-like nuclei

5. Healing and chronic valve scarring

Repeated or severe episodes of rheumatic valvulitis heal by fibrosis. This produces:
  • Thickened valve leaflets
  • Fusion of commissures
  • Fusion and shortening of chordae tendineae
  • Calcification in later disease
  • Reduced valve mobility
The mitral valve is most often affected, followed by the aortic valve.

6. Resulting valve disease and complications

Chronic scarring most classically causes mitral stenosis, often years after the initial episode.
Mitral stenosis leads to:
Mitral obstruction
→ increased left atrial pressure
→ left atrial enlargement
→ pulmonary venous congestion
→ pulmonary hypertension
→ right ventricular hypertrophy/failure
Left atrial enlargement also predisposes to:
  • Atrial fibrillation
  • Blood stasis in the left atrium
  • Left atrial thrombus
  • Systemic embolism, including ischemic stroke

Flow summary

Group A streptococcal pharyngitis
→ immune response against M protein
→ molecular mimicry and cross-reactive antibodies/T cells
→ acute rheumatic fever with pancarditis and valvulitis
→ recurrent inflammation and healing by fibrosis
→ valve deformity, especially mitral stenosis
→ atrial fibrillation, pulmonary hypertension, heart failure, and embolic stroke.
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