What is the treatment approach for mitral regurgitation?

Treatment Approach for Mitral Regurgitation

The treatment of mitral regurgitation requires a tailored approach based on whether the condition is primary (degenerative) or secondary (functional), with surgical repair being the preferred intervention for severe primary MR and guideline-directed medical therapy (GDMT) being the first-line approach for secondary MR, followed by transcatheter edge-to-edge repair (TEER) in appropriate candidates. 1, 2

Classification and Assessment

• Echocardiography is essential to determine whether MR is primary or secondary, which guides subsequent management decisions 1, 2
• Severe primary MR is defined by vena contracta ≥7 mm, effective regurgitant orifice area (EROA) ≥0.4 cm², regurgitant fraction ≥50%, and regurgitant volume ≥60 mL/beat 1
• For secondary MR, lower thresholds may apply with EROA ≥0.3 cm² when the regurgitant orifice is elliptical 1
• Exercise echocardiography should be considered for patients with exercise-induced symptoms to assess dynamic worsening of MR 2
• Cardiovascular magnetic resonance (CMR) can be used when echocardiographic measurements are ambiguous 1

Management of Primary Mitral Regurgitation

• Surgery is indicated for symptomatic patients with severe primary MR regardless of left ventricular function 1, 2
• For asymptomatic patients with severe primary MR, surgical intervention is indicated when:
  • LVEF ≤60% and/or LV end-systolic diameter ≥40 mm 1, 2
  • New-onset atrial fibrillation or pulmonary artery systolic pressure >50 mmHg 2
• Mitral valve repair is strongly preferred over replacement when technically feasible (>80-90% repair rates in specialized centers) 1, 2
• Surgery should be performed in a heart valve center with high repair rates to ensure optimal outcomes 1

Management of Secondary Mitral Regurgitation

• GDMT is mandatory as the first step for all patients with secondary MR 1, 2
• GDMT includes ACE inhibitors/ARBs, beta-blockers, and mineralocorticoid receptor antagonists 1, 2
• Cardiac resynchronization therapy (CRT) should be considered in appropriate candidates as it may reduce MR severity through increased closing force and resynchronization of papillary muscles 2
• Surgery is indicated in patients with severe secondary MR undergoing coronary artery bypass grafting and LVEF >30% 3, 2
• Transcatheter edge-to-edge repair (TEER) should be considered for patients with severe secondary MR, LVEF >30%, persistent symptoms despite optimal medical therapy, and no indication for coronary revascularization 1, 3

Medical Management

• Diuretics are first-line therapy for patients with fluid overload manifestations such as lower extremity edema 2
• Beta-blockers may lessen MR, prevent deterioration of left ventricular function, and improve survival in asymptomatic patients with moderate to severe primary MR 4
• ACE inhibitors and ARBs can reduce MR severity, especially in asymptomatic patients 4
• Caution: In hypertrophic cardiomyopathy or mitral valve prolapse, vasodilators can increase the severity of MR 4

Surveillance and Follow-up

• Asymptomatic patients with severe MR require clinical and echocardiographic follow-up every 6-12 months 1, 2
• Patients with moderate MR should have clinical evaluation every 6-12 months with annual echocardiography 2
• Patients with mild MR should be monitored every 3-5 years 2
• Serum biomarkers (e.g., BNP) may help guide optimal timing of intervention in asymptomatic patients with severe MR 1, 2

Special Considerations

• For acute severe MR, management includes vasodilator therapy, inotropic support if hemodynamically unstable, and mechanical support with intra-aortic balloon pump if needed 1
• Risk stratification should include assessment of STS-PROM score, frailty, organ system compromise, and procedure-specific impediments 1, 2
• Multidisciplinary heart team discussion is essential to guide optimal intervention strategy, considering valve morphology, MR etiology, patient comorbidities, and surgical risk 2

Emerging Therapies

• Percutaneous treatment options have been developed as alternatives for patients at high surgical risk 5
• Transcatheter mitral valve interventions are evolving rapidly and provide options for patients previously deemed inoperable 3
• New transcatheter devices in development and clinical trials promise to further provide a growing array of management options for heart failure patients with symptomatic secondary MR 3