What are the symptoms and management of mitral regurgitation?

Symptoms and Management of Mitral Regurgitation

The most common symptoms of mitral regurgitation include exertional dyspnea, fatigue, and palpitations, with many patients remaining asymptomatic until advanced stages despite severe regurgitation. 1

Symptoms of Mitral Regurgitation

Clinical Presentation

• Common symptoms:
  • Exertional dyspnea (most common)
  • Fatigue
  • Palpitations 1
  • In severe cases: pulmonary edema and cardiogenic shock 1

Important Clinical Considerations

• Many patients remain asymptomatic despite severe MR due to enhanced left atrial compliance 1
• Patients often subconsciously reduce activity levels to avoid symptoms 1
• Family members may notice decreased activity or symptoms before patients recognize them 1
• Acute MR (e.g., from papillary muscle rupture) presents with sudden hemodynamic deterioration 1

Physical Examination Findings

• Primary MR:

  • Holosystolic murmur at apex radiating to axilla
  • Diastolic filling complex (S3 plus short diastolic murmur) suggests significant regurgitant volume 1
  • Anterior leaflet flail: murmur radiates to axilla and left infrascapular area
  • Posterior leaflet flail: murmur radiates anteriorly (can be confused with systolic ejection murmurs) 1

• Secondary MR:

  • Murmur usually best heard at apex radiating to axilla
  • S3 gallop may be present but harder to interpret due to underlying LV dysfunction 1

Diagnostic Evaluation

Echocardiography

• Essential for establishing diagnosis, etiology, and severity of MR 1
• Should assess:
  • Valve anatomy and function
  • Left ventricular size and function
  • Left atrial size
  • Pulmonary artery pressure
  • Associated tricuspid regurgitation 1

Exercise Testing

• Valuable in asymptomatic patients to:
  • Elicit symptoms
  • Demonstrate reduced exercise capacity
  • Reveal elevated pulmonary artery pressures
  • Show worsening MR or failure of ventricular function to augment normally 1
• 6-minute walk test: simple, inexpensive alternative for frail or elderly patients 1

Management Approach

Primary Mitral Regurgitation

Medical Management

• Limited role in primary MR
• Symptomatic management of heart failure symptoms if present
• Control of hypertension if present

Surgical Intervention

• Indications for surgery:
  • Symptomatic severe MR
  • Asymptomatic severe MR with:
    • LV dysfunction (LVEF <60%)
    • LV dilation (end-systolic dimension >40 mm)
    • Recent-onset atrial fibrillation
    • Pulmonary hypertension 1
  • Mitral valve repair preferred over replacement when feasible 1

Secondary Mitral Regurgitation

Medical Management

• Optimize guideline-directed medical therapy for heart failure:
  • ACE inhibitors/ARBs
  • Beta-blockers
  • Mineralocorticoid receptor antagonists
  • Diuretics for volume control 2, 3
• Management of atrial fibrillation when present 3

Device Therapy

• Consider cardiac resynchronization therapy (CRT) when indicated 2, 3
• Can significantly reduce MR severity in appropriate candidates 3

Interventional Options

• Surgery indicated in patients with severe secondary MR undergoing CABG with LVEF >30% 1
• Consider surgery in symptomatic patients despite optimal medical therapy with low surgical risk 1
• Transcatheter edge-to-edge repair (TEER) for selected patients with:
  • Moderate-severe MR
  • Poor LV systolic function
  • High surgical risk 3
  • Has shown reduction in heart failure hospitalizations and mortality 3

Follow-up and Monitoring

• Asymptomatic severe MR: serial echocardiography every 6-12 months 2
• Monitor for:
  • Development of symptoms
  • LV dysfunction or dilation
  • Pulmonary hypertension
  • New-onset atrial fibrillation 2

Special Considerations

Acute Mitral Regurgitation

• Presents with sudden hemodynamic deterioration
• Often due to papillary muscle rupture (typically from small infarct of posteromedial papillary muscle) 1
• Requires emergency surgery with intra-aortic balloon pump placement during preparation 1

Mitral Regurgitation with Chronic Kidney Disease

• Requires multidisciplinary approach involving cardiologist, cardiac surgeon, nephrologist 2
• CKD stage 4-5 patients have highest mortality risk regardless of intervention type 2

Prognosis

• Untreated severe MR results in high mortality and frequent hospitalizations for heart failure 4
• Early surgical intervention significantly improves symptoms and long-term survival 5
• In secondary MR with advanced heart failure, severity correlates with systolic dysfunction, ventricular dilation, and pulmonary hypertension 6

By understanding the symptoms and implementing appropriate management strategies based on MR etiology, severity, and patient characteristics, outcomes can be significantly improved for patients with mitral regurgitation.