Can rheumatic heart disease be diagnosed in a patient with a history of rheumatic fever who presents only with mitral regurgitation (no mitral stenosis), and what is the recommended management?

Rheumatic Heart Disease with Isolated Mitral Regurgitation

Yes, rheumatic heart disease can absolutely be diagnosed in a patient with a history of rheumatic fever who presents with isolated mitral regurgitation without mitral stenosis, and this patient requires secondary antibiotic prophylaxis and regular echocardiographic surveillance. 1

Diagnostic Framework

In Patients with Prior Rheumatic Fever

Any structural or functional valve abnormality in a patient with documented acute rheumatic fever must be considered RHD until proven otherwise. 1 This is a critical principle that supersedes the need for multiple morphological features in patients without a known history.

• The World Heart Federation 2012 guidelines explicitly state that in individuals with a history of definite acute rheumatic fever, any valvular abnormality should be presumed rheumatic in origin 1
• This applies even when only isolated mitral regurgitation is present without stenosis 1

Echocardiographic Criteria for Definite RHD

For patients without a prior history of rheumatic fever, the diagnosis requires:

Subcategory A (Definite RHD): Pathological mitral regurgitation PLUS at least two morphological features of RHD affecting the mitral valve 1

The morphological features include:

• Anterior mitral leaflet thickening (≥3 mm) 1
• Chordal thickening 1
• Restricted leaflet motion 1
• Excessive leaflet tip motion during systole 1

However, isolated mitral regurgitation alone can represent early RHD, particularly in younger patients (≤20 years) from endemic regions, where it qualifies as "borderline RHD" requiring close follow-up 1

Clinical Context Supporting RHD Diagnosis

Prevalence of Isolated Mitral Regurgitation in RHD

• Mitral regurgitation is the most common manifestation of RHD in young patients, occurring in 87-94% of cases 2
• The mitral valve is affected in 99.3% of echocardiographic RHD cases and 100% of postmortem examinations 1, 2
• Isolated mitral regurgitation without stenosis is well-documented in rheumatic heart disease, especially in countries with high rheumatic fever prevalence 3
• Surgical and pathological studies confirm that 5-7.5% of patients with documented acute rheumatic fever and severe valvular disease may have isolated regurgitation without meeting full morphological criteria 1

Distinguishing Features

Look for these characteristic echocardiographic findings that suggest rheumatic etiology:

• "Hockey stick" deformity of the anterior mitral leaflet (restricted motion with thickening) 2
• Chordal thickening and fusion 2
• Posterior leaflet restriction with anterior leaflet dominance 1

Critical pitfall: Exclude other causes before confirming RHD diagnosis:

• Congenital abnormalities (cleft mitral valve, double-orifice valve, parachute valve) 2
• Mitral valve prolapse (which can coexist with or mimic RHD) 3, 4
• Degenerative disease (rare in young patients) 1
• Infective endocarditis (differentiated by clinical findings and vegetation presence) 1

Management Recommendations

Secondary Prophylaxis

All patients with established RHD require continuous antimicrobial prophylaxis for at least 10 years or until age 40 years, whichever is longer. 5 This applies regardless of whether stenosis is present.

• Benzathine penicillin G every 3-4 weeks is the preferred regimen 5
• This prevents recurrent acute rheumatic fever episodes that cause progressive valve damage 5

Disease Staging and Risk Stratification

Using the 2023 World Heart Federation staging system 1:

Stage B (Mild RHD): Mild mitral regurgitation with at least one morphological feature (age ≤20 years) or two features (age >20 years)

• Moderate risk of progression
• Requires secondary prophylaxis 1

Stage C (Advanced RHD): Moderate or severe mitral regurgitation

• High risk of clinical complications
• May require medical or surgical intervention 1

Surveillance Strategy

• Echocardiographic follow-up every 1-2 years for mild disease to monitor progression 1
• More frequent monitoring (every 6-12 months) if regurgitation is moderate or worsening 1
• Assess for development of stenosis, left atrial enlargement, pulmonary hypertension, and left ventricular dysfunction 1

When to Consider Intervention

Surgical or percutaneous intervention becomes necessary when:

• Severe mitral regurgitation develops with symptoms (NYHA class II-IV) 1
• Left ventricular systolic dysfunction occurs (ejection fraction <60%) 1
• Progressive left ventricular dilatation is documented 1
• Pulmonary hypertension develops 1

Important caveat: The natural history of early RHD is heterogeneous—30% of mild cases may regress spontaneously, while others progress despite prophylaxis 1. This underscores the importance of individualized monitoring intervals based on disease severity and progression rate.

Special Consideration for Young Patients

In patients aged ≤20 years with isolated pathological mitral regurgitation and a history of rheumatic fever:

• This qualifies as definite RHD requiring full secondary prophylaxis 1
• Morphological features may take time to develop after the initial acute rheumatic fever episode 1
• The absence of multiple morphological features does not exclude RHD diagnosis when clinical history is positive 1