Rheumatic Heart Disease (RHD)

Rheumatic Heart Disease (RHD) is a chronic and progressive condition resulting from damage to the heart following one or more episodes of Acute Rheumatic Fever (ARF). It is characterized by permanent structural damage to cardiac valves, chordae tendineae, and papillary muscles. ARF primarily arises as a non-suppurative sequela of infection with group A β-hemolytic streptococci (GABHS).

Etiology: RHD develops due to a delayed autoimmune response triggered by GABHS infection.

Pathophysiology:

• The immune system cross-reacts with host tissues due to molecular mimicry between streptococcal M proteins and human proteins.
• Affects multiple systems including:
  • Heart: Pancarditis during ARF
  • Joints: Migratory arthritis
  • Central Nervous System (CNS): Sydenham chorea
  • Skin: Erythema marginatum and subcutaneous nodules

Non-Specific Features

• Peak age: 6–15 years.
• History of sore throat: 2–4 weeks before presentation.
• Symptoms: Fever, myalgia, abdominal pain, epistaxis, and cough.
• Duration: Typically resolves in 5–7 days.

Syndromic Features (Major Criteria)

1. Arthritis:
   • Migratory polyarthritis affecting large joints.
   • Pain, swelling, and warmth.
   • Seen in ~75% of cases.
2. Pancarditis:
   • Inflammation of the entire heart, present in 50% of ARF cases.
   • Clinical signs:
     • Mitral regurgitation.
     • Heart failure symptoms: Cough, dyspnea, leg swelling.
     • Murmur: Grade III-IV holosystolic murmur heard best at the apex, radiating to the axilla.
3. Sydenham Chorea:
   • Neurological and psychological manifestations in 15% of cases.
   • Features: Tremors, altered handwriting, milkmaid grip, and psychological symptoms like insomnia, hallucinations, mania, or depression.
   • Common in prepubertal females; manifests 2–6 months post-infection.
4. Erythema Marginatum:
   • Circular rash with a pale center and red margins, affecting the trunk and limbs (5–10% of cases).
5. Subcutaneous Nodules:
   • Painless, firm nodules under the skin, rare (<5% of cases).

The Modified Duckett Jones Criteria is used for diagnosing ARF.

• Major Criteria: Syndromic features (arthritis, pancarditis, Sydenham chorea, erythema marginatum, subcutaneous nodules).
• Minor Criteria:
  • Clinical: Fever, arthralgia.
  • Laboratory: Elevated ESR, prolonged PR interval (first-degree heart block), and evidence of recent GABHS infection (e.g., throat swab culture or rising antibody titer).

Effective diagnosis of ARF and RHD relies on clinical assessment, laboratory investigations, and imaging techniques to evaluate systemic involvement, confirm underlying infections, and identify cardiac damage.

1. Clinical Assessment

• Thorough Evaluation:
  • Symptoms of ARF include fever, arthralgia, and syndromic features such as arthritis, pancarditis, Sydenham chorea, erythema marginatum, and subcutaneous nodules.
  • Diagnostic Criteria:
    • Major Criteria: Arthritis, pancarditis, Sydenham chorea, erythema marginatum, subcutaneous nodules.
    • Minor Criteria: Fever, arthralgia.
• Diagnostic Approach: Diagnosis follows the Modified Duckett Jones Criteria:
  • 2 Major Criteria, or 1 Major + 2 Minor Criteria, along with evidence of preceding GABHS infection.

2. Laboratory Investigations

1. Marker of Cardiac and Systemic Inflammation:
   • Elevated ESR: Non-specific inflammation marker; part of the minor criteria.
2. Evidence of Recent GABHS Infection:
   • Throat Swab Culture: A positive culture for GABHS strongly supports the diagnosis.
   • Rapid Antigen Test: Confirms Group A Streptococcal presence quickly.
   • Streptococcal Antibody Titers:
     • Antistreptolysin O (ASO) Titer: >333 Todd units in children, >250 Todd units in adults.
     • Antihyaluronidase and Antideoxyribonuclease B Titers: >240 Todd units in children, >120 Todd units in adults.

3. Imaging and Other Diagnostic Modalities

1. Echocardiography (ECHO):
   • Crucial for assessing valvular defects, abnormal blood flow, and structural damage in RHD.
   • In cases of Infective Endocarditis, ECHO can identify vegetations and confirm underlying heart disease.
2. Chest X-Ray (CXR):
   • May show straightening of the left heart border due to left atrial enlargement in advanced RHD.
3. Electrocardiogram (ECG):
   • Identifies prolonged PR interval, arrhythmias, left atrial enlargement, and left ventricular hypertrophy. Prolonged PR interval is a sign of first-degree heart block (minor criterion).
4. Cardiac Catheterization:
   • Reserved for detailed structural and functional cardiac assessment in complex cases.

4. Investigations for Infective Endocarditis

1. Serial Blood Cultures:
   • At least 3 blood samples taken to detect causative microorganisms.
   • If cultures remain negative after 48 hours, additional samples are required.
2. ECHO:
   • Identifies vegetations, valve destruction, and regurgitation.
3. Full Blood Count (FBC):
   • May show anemia and left shift leukocytosis, indicating infection or inflammation.
4. Urinalysis:
   • Microscopic hematuria, if present, can be associated with embolic phenomena.

Key Diagnostic Notes

• Jones Criteria:
  • A single major criterion can diagnose ARF in cases of:
  • Isolated chorea.
  • Indolent carditis.
  • Recurrence in a patient with previous ARF.
• Diagnostic Confirmation: Evidence of preceding GABHS infection is critical for diagnosis, emphasizing the importance of throat swabs, antigen tests, and antibody titers.

Mitral Valve Disease in RHD

• Prevalence: Affects 90% of RHD patients.
• Mitral Stenosis:
  • More common in women.
  • Pathology: Valve thickening, chordae tendineae shortening, and cusp fusion.
  • Clinical features:
    • Asymptomatic until valve orifice < 2 cm².
    • Symptoms: Cough, hemoptysis, dysphagia, palpitations, and heart failure.
    • Murmur: Mid-diastolic rumble with an opening snap.
• Mitral Regurgitation:
  • Symptoms: Bounding pulse, heart failure.
  • Murmur: Holosystolic murmur at the apex, radiating to the axilla.

Aortic Valve Disease

• Regurgitation:
  • Clinical features: Wide pulse pressure, Quincke’s sign, De Musset’s sign, and pistol-shot sounds over femoral arteries.
  • Murmur: Diastolic murmur at the right sternal edge.
• Aortic Stenosis:
  • Clinical features: Dyspnea, fainting, small volume pulse, and ejection systolic murmur radiating to the carotids.
  • Associated with: William’s Syndrome.

Pulmonary and Tricuspid Valve Disease

While less common, RHD can also affect the pulmonary and tricuspid valves.

Management of Acute Rheumatic Fever (ARF)

• Bed Rest: Adequate rest is crucial during the acute phase of ARF to alleviate inflammation and reduce strain on the heart.
• Anti-inflammatory Therapy:
  • Aspirin is commonly used to reduce inflammation, fever, and pain. It is the first-line treatment for controlling symptoms in the acute phase.
  • Steroids may be required in severe cases or when aspirin fails to adequately control symptoms, especially in cases involving the heart.
• Heart Failure Management: If heart failure develops as a result of pancarditis, it must be promptly addressed with appropriate pharmacological therapy and, if necessary, other interventions.
• Management of Chorea: Medications such as haloperidol or phenobarbital may be used to control the involuntary movements associated with chorea.

Management of Rheumatic Heart Disease (RHD)

• Valvular Repair: In cases of significant valve damage, the goal is to repair or replace the affected heart valves. This may require either surgical intervention or a less invasive percutaneous procedure, depending on the severity.
• Heart Failure Management: RHD often leads to chronic heart failure due to valvular dysfunction. The management of heart failure in these patients should focus on controlling symptoms with medications such as ACE inhibitors, diuretics, and beta-blockers, alongside regular monitoring to assess disease progression.

Prevention of Acute Rheumatic Fever (ARF) and Rheumatic Heart Disease (RHD)

Primary Prophylaxis

This aims to prevent the initial development of ARF by treating Group A Beta-Hemolytic Streptococcal (GABHS) pharyngitis.

• Oral penicillin is given for 7-10 days to patients with suspected or confirmed GABHS pharyngitis, effectively eradicating the infection and preventing the onset of ARF.

Secondary Prophylaxis

This is critical for individuals with a history of ARF to prevent recurrent episodes.

• Intramuscular (IM) benzathine penicillin is administered every 3-4 weeks to reduce the risk of recurrence.
• The duration of secondary prophylaxis is determined by the severity of carditis:
  • No carditis: 5 years after the initial ARF episode or until the patient reaches 18 years of age, whichever is longer.
  • Mild or healed carditis: 10 years or until age 25, whichever is longer.
  • Severe carditis or valvular surgery: Lifelong prophylaxis is required.

Additional Considerations for Prophylaxis

The duration of prophylaxis depends on several factors:

• Age of the patient.
• Number of previous ARF attacks.
• Severity of existing heart disease.
• Risk of exposure to streptococcal infections.

Infective Endocarditis Risk

Patients with RHD are at an increased risk for infective endocarditis, particularly during invasive procedures. Prophylactic antibiotics are often recommended before dental or surgical procedures to reduce this risk.

Goal of Treatment and Prevention

The main aim of treatment and prophylaxis is to manage symptoms, prevent disease progression, and improve the long-term prognosis for patients with ARF and RHD. By adhering to prophylactic guidelines, the incidence of recurrent infections and subsequent heart damage can be minimized.

Rheumatic Heart Disease remains a significant health burden in low-resource settings. Early diagnosis, effective treatment of ARF, and robust prophylaxis programs are critical to preventing RHD and its complications.