Management of Mitral Regurgitation

Initial Classification and Diagnostic Assessment

The American College of Cardiology and European Heart Society recommend echocardiography to distinguish primary from secondary mitral regurgitation, as this classification determines the management pathway 1, 2
Severe primary mitral regurgitation is defined by a vena contracta ≥7 mm, EROA ≥0.4 cm², regurgitant fraction ≥50%, or regurgitant volume ≥60 mL/beat 1, 2
Severe secondary mitral regurgitation is defined by an EROA ≥0.3 cm² if the regurgitant orifice is elliptical in nature 3, 1
Cardiovascular magnetic resonance (CMR) should be used when echocardiographic measurements are ambiguous or uncertain to quantify LV/RV function, chamber size, and MR severity 3, 1

The European Heart Society recommends surgery for all symptomatic patients with severe primary mitral regurgitation, regardless of left ventricular ejection fraction 3, 1, 2
Mitral valve repair is strongly preferred over replacement when anatomically feasible, as it provides superior outcomes 5, 2
Surgery should be performed at high-volume centers with documented high repair rates (>90% for isolated posterior leaflet prolapse) and operative mortality <1% 5

Guideline-directed medical therapy (GDMT) must be maximized before considering any intervention for secondary mitral regurgitation 1, 2
The American College of Cardiology recommends ACE inhibitors or ARBs as first-line therapy, beta-blockers to prevent LV deterioration, mineralocorticoid receptor antagonists, diuretics for fluid overload, and nitrates for acute dyspnea 1, 2
Cardiac resynchronization therapy (CRT) should be implemented in patients who meet guideline-directed criteria (typically LVEF ≤35%, QRS ≥150 ms, LBBB) 1, 2
Transcatheter edge-to-edge repair (TEER) should be considered for patients with severe secondary mitral regurgitation, LVEF 20-50%, persistent NYHA class II-IV symptoms despite optimal medical therapy and CRT when indicated 3, 2

Asymptomatic severe mitral regurgitation requires clinical and echocardiographic follow-up every 6-12 months 3, 1, 2
Moderate mitral regurgitation requires clinical evaluation every 6-12 months with annual echocardiography 1, 2
Mild mitral regurgitation should be monitored every 3-5 years 1, 2

All intervention decisions must involve multidisciplinary team (MDT) discussion by the heart team, including assessment of valve morphology, MR etiology, patient comorbidities, and surgical risk 3, 1, 2
Input from a cardiologist with experience managing heart failure is essential for secondary mitral regurgitation 2