What is the management approach for patients with bileaflet mitral valve prolapse and moderate to severe mitral regurgitation (MR)?

Management of Bileaflet Mitral Valve Prolapse with Moderate to Severe MR

For patients with bileaflet mitral valve prolapse and moderate to severe mitral regurgitation, surgical mitral valve repair is the definitive treatment when symptoms are present or when asymptomatic patients develop left ventricular dysfunction (LVEF ≤60% or LVESD ≥40 mm), new-onset atrial fibrillation, or pulmonary hypertension (SPAP >50 mmHg at rest). 1, 2

Surgical Intervention Criteria

Symptomatic Patients

• Surgery is indicated for all symptomatic patients (NYHA class II-IV) with severe MR, regardless of left ventricular function. 3, 1
• Early surgery within 2 months of meeting guideline indications is associated with better outcomes, as even mild symptoms at time of surgery correlate with worse cardiac function postoperatively. 3

Asymptomatic Patients with Severe MR

Surgery is indicated when any of the following are present:

• Left ventricular dysfunction: LVEF ≤60% or LVESD ≥40 mm (≥22 mm/m² BSA in small stature patients) 3, 1
• New-onset atrial fibrillation 3, 1
• Pulmonary hypertension: SPAP >50 mmHg at rest 3

Additional Considerations for Asymptomatic Patients

Surgery should be considered (Class IIa-IIb) in highly selected asymptomatic patients when:

• High likelihood of durable repair (>95% success rate) at experienced centers with <1% operative mortality 3
• Flail leaflet with LVESD ≥40 mm 3
• Severe left atrial dilatation (volume index ≥60 mL/m² BSA) in sinus rhythm 3
• Exercise-induced pulmonary hypertension (SPAP ≥60 mmHg on exercise) 3

Surgical Technique for Bileaflet Prolapse

Mitral valve repair is strongly preferred over replacement and is technically feasible in the vast majority of bileaflet prolapse cases. 3, 1

Repair Techniques

The specific approach depends on pathoanatomy:

For balanced bileaflet prolapse with central regurgitant jet:

• Ring-only repair (annuloplasty alone) provides excellent 10-year freedom from recurrent MR (97%) with minimal risk of systolic anterior motion (5%). 4

For complex bileaflet prolapse:

• Nonresection techniques using PTFE neochord reconstruction or ipsilateral chordal transfer combined with annuloplasty ring 3, 2
• Chordal transfer technique (moving chords from secondary to primary position) 3
• Hybrid approaches combining multiple techniques as needed 5

For diffuse myxomatous disease:

• Sliding leaflet valvuloplasty with annuloplasty ring for extensive posterior leaflet involvement 3
• Combination procedures often required (chordal transfer, neochords, edge-to-edge repair) 5

Surgical Outcomes

• Bileaflet prolapse repair achieves comparable durability to posterior leaflet-only prolapse, with 10-year freedom from reoperation of 97% and freedom from recurrent moderate or greater MR of 89-90%. 6, 5
• Hospital mortality is essentially zero in experienced centers. 6, 5
• Referral to experienced mitral valve surgeons at high-volume centers is critical for optimal outcomes, particularly for complex bileaflet pathology. 3, 1, 2

Medical Management

For Patients Not Meeting Surgical Criteria

• No role for vasodilators (including ACE inhibitors) in chronic primary MR without heart failure symptoms. 1
• Beta-blockers may be used for symptomatic arrhythmias or palpitations. 1
• Anticoagulation (INR 2-3) is indicated for patients with atrial fibrillation, history of systemic embolism, or left atrial thrombus. 1

For Advanced Heart Failure (Non-Surgical Candidates)

• ACE inhibitors, beta-blockers, and spironolactone for guideline-directed medical therapy. 1
• Consider cardiac resynchronization therapy if indicated. 3

Percutaneous Intervention

Transcatheter edge-to-edge repair (TEER) may be considered for high-risk or prohibitive surgical risk patients with favorable anatomy and life expectancy >1 year. 3, 1

• This is a Class IIb recommendation for primary MR in patients who cannot undergo surgery. 3

Surveillance Protocol

Moderate MR (Not Meeting Surgical Criteria)

• Clinical follow-up every 6 months with annual echocardiography 3, 1

Severe MR (Asymptomatic, Not Meeting Surgical Criteria)

• Clinical evaluation every 6 months with annual echocardiography 1
• More frequent monitoring if borderline values or progressive changes. 1

Post-Surgical Follow-up

• Baseline echocardiography at discharge or 1-3 months postoperatively for future comparison. 3, 1
• Longitudinal echocardiography dictated by clinical findings. 3

Critical Pitfalls to Avoid

Do not delay surgery until symptoms develop or significant LV dysfunction occurs, as this leads to worse outcomes. 3, 1 Patients with bileaflet prolapse often meet surgical indications with less severe MR than posterior leaflet-only prolapse due to more pronounced cardiac enlargement. 7

Avoid mitral valve replacement without attempting repair in patients with isolated posterior leaflet flail and no calcification. 3 These patients should not undergo replacement unless repair has been attempted and failed. 3

Recognize that echocardiographic assessment can underestimate MR severity in late-systolic prolapse. 1 Physical examination findings (very late soft systolic murmur, clear lungs, no diastolic filling sound) may suggest only mild-to-moderate MR despite potentially misleading quantitative echo parameters. 1