What is the significance of rheumatic fever in a case of established Rheumatic Heart Disease (RHD)?

Significance of Rheumatic Fever in Established Rheumatic Heart Disease

In patients with established Rheumatic Heart Disease (RHD), recurrent episodes of rheumatic fever significantly increase the risk of worsening valvular damage and should be prevented through continuous antibiotic prophylaxis, which must be maintained for at least 10 years or until age 40 (whichever is longer), and sometimes lifelong in cases with persistent valvular disease. 1, 2

Pathophysiological Relationship

Rheumatic Heart Disease (RHD) is a direct consequence of acute rheumatic fever (ARF), which results from an abnormal autoimmune response to group A streptococcal (GAS) infection in genetically susceptible individuals. The relationship between these conditions is critical:

• RHD represents a complication of rheumatic fever, occurring after either a single severe episode or multiple recurrent episodes 1
• Each recurrence of rheumatic fever can cause progressive valve damage, worsening existing RHD 1, 2
• A GAS infection does not need to be symptomatic to trigger a recurrence of rheumatic fever 1
• Recurrent episodes can occur even when symptomatic infections are treated optimally 1

Clinical Impact of Recurrent Rheumatic Fever

The significance of rheumatic fever in established RHD is primarily related to disease progression:

• Patients with previous rheumatic carditis who experience recurrent episodes are at high risk for worsening severity of existing valvular lesions 1
• Recurrences can also lead to new onset of rheumatic heart disease in individuals who did not develop cardiac manifestations during their first attack 1
• The mortality rate is significantly higher among RHD cases compared to those with acute rheumatic fever alone 3
• RHD accounts for most cardiovascular morbidity and mortality in young people in developing countries, leading to approximately 250,000 deaths per year worldwide 4

Prevention Strategies

Secondary Prophylaxis

Secondary prophylaxis is the cornerstone of management for established RHD:

• Continuous antimicrobial prophylaxis is required rather than just recognition and treatment of acute episodes of streptococcal pharyngitis 1

• The American Heart Association recommends the following duration of prophylaxis 1, 2:

  Clinical Scenario	Duration of Prophylaxis
  RHD with persistent valvular disease	10 years after last episode or until age 40, whichever is longer (sometimes lifelong)
  RHD with carditis but no persistent valvular disease	10 years after last episode or until age 21, whichever is longer
  Rheumatic fever without carditis	5 years after last episode or until age 21, whichever is longer

• Secondary prophylaxis is required even after valve replacement 1, 2

Recommended Prophylactic Regimens

• First choice: Benzathine penicillin G, 1.2 million units intramuscularly every 4 weeks (or every 3 weeks in high-risk situations) 1, 2
• Alternatives for penicillin-allergic patients:
  • Penicillin V potassium: 250 mg orally twice daily 1
  • Sulfadiazine: 1 g orally once daily 1
  • Erythromycin: 250 mg orally twice daily (for patients allergic to penicillin and sulfonamides) 5

Monitoring and Follow-up

For patients with established RHD:

• Regular echocardiographic assessment to monitor valvular function and disease progression 1, 2
• Monitoring of acute phase reactants (ESR, CRP) until normalized 2
• Regular cardiac follow-up with strict adherence to prophylaxis regimen 2
• Early detection and treatment of streptococcal infections in family members 1

Risk Factors for Recurrence

Several factors increase the risk of recurrence of rheumatic fever in patients with established RHD:

• Multiple previous attacks of rheumatic fever 1
• Increased exposure to streptococcal infections (children, adolescents, teachers, healthcare workers) 1
• Poor socioeconomic status 3
• Undernutrition 3
• Poor compliance with prophylactic antibiotics 2, 3

Conclusion

The significance of rheumatic fever in established RHD cannot be overstated. Each recurrence poses a substantial risk for worsening valvular damage, leading to increased morbidity and mortality. Continuous antibiotic prophylaxis remains the most effective strategy to prevent recurrences and halt disease progression. The duration of prophylaxis should be determined based on the presence of carditis and residual heart disease, with lifelong prophylaxis considered in cases with persistent valvular damage.