What is the management approach for Mitral Regurgitation (MR)?

Management of Mitral Regurgitation

The management of mitral regurgitation (MR) requires a multidisciplinary team approach with treatment strategies tailored to the etiology (primary vs. secondary MR), severity, symptoms, and cardiac function. 1

Classification and Initial Assessment

Primary vs. Secondary MR

• Primary MR: Direct valve abnormality
• Secondary MR: Dysfunction of surrounding structures (ventricular/annular)

Key Diagnostic Evaluations

• Echocardiography: Essential for quantifying severity, mechanism, and ventricular function 1
  • Severe MR defined as EROA ≥0.4 cm² and regurgitant volume ≥60 mL/beat for primary MR
  • For secondary MR, threshold may be lower (EROA ≥0.3 cm² in ESC guidelines) 1
• CMR: Useful when echocardiographic measurements are ambiguous 1
• Exercise testing: May reveal latent symptoms or exercise-induced pulmonary hypertension 1
• Biomarkers: BNP/NT-proBNP helpful for prognostication 1

Management Algorithm

1. Asymptomatic Severe Primary MR

• Close monitoring: Echocardiography every 6-12 months 1, 2
• Surgical intervention indicated when:
  • LV dysfunction develops (LVEF ≤60%)
  • LV dilation (LVESD ≥40 mm)
  • Pulmonary hypertension
  • New-onset atrial fibrillation 2
• Consider earlier surgical repair in selected patients with high likelihood of successful valve repair 3

2. Symptomatic Severe Primary MR

• Surgical intervention (repair preferred over replacement when feasible) 1
• For high surgical risk patients: Consider transcatheter mitral valve repair (TMVR) 2, 4

3. Secondary MR Management

• Optimize guideline-directed medical therapy (GDMT) first 1, 2, 5:
  • ACE inhibitors/ARBs
  • Beta-blockers
  • Mineralocorticoid receptor antagonists
  • Diuretics for volume control
• Consider cardiac resynchronization therapy (CRT) when indicated 2, 5
• For persistent symptomatic severe MR despite optimal GDMT:
  • Transcatheter edge-to-edge repair (TEER) may be considered for suitable patients 1
  • Surgical options (repair or replacement) for appropriate candidates 1

Patient Selection for TEER in Secondary MR

Inclusion Criteria

• Severe secondary MR
• Symptomatic heart failure (NYHA class II-IV) despite optimal GDMT
• LVEF 20-50%
• LV end-systolic diameter ≤70 mm
• Recent heart failure hospitalization or elevated natriuretic peptides
• Suitable valve anatomy 1

Exclusion Criteria

• Severe disability/frailty
• Specific cardiomyopathies (hypertrophic, restrictive, infiltrative)
• Severe pulmonary hypertension (PASP >70 mmHg)
• Hemodynamic instability
• Moderate/severe RV dysfunction
• Mitral valve orifice area <4.0 cm² 1

Medical Therapy

• Beta-blockers: May lessen MR, prevent LV function deterioration, and improve survival in asymptomatic patients with moderate-severe primary MR 6
• RAAS inhibitors: Can reduce MR in asymptomatic patients 6
• Caution: Vasodilators may worsen MR in hypertrophic cardiomyopathy or mitral valve prolapse 6

Follow-up Recommendations

• Asymptomatic severe MR: Echocardiography every 6-12 months 1
• Post-intervention: Assessment at baseline, discharge, 30 days, 6 months, and 1 year 2
• Moderate MR: Regular follow-up with serial echocardiography 2

Common Pitfalls to Avoid

• Failure to distinguish between primary and secondary MR 1
• Incomplete echocardiographic assessment of MR severity 1
• Delayed referral for intervention in asymptomatic patients with progressive LV dysfunction 3
• Underutilization of GDMT in secondary MR before considering interventional approaches 1, 5
• Inappropriate patient selection for transcatheter interventions 1

The management of MR has evolved significantly with expanded therapeutic options. A heart team discussion involving cardiologists, cardiac surgeons, and interventionalists is essential for optimal decision-making, particularly for complex cases 1, 2.