What are the management and treatment options for a patient with mitral valve prolapse?

Management and Treatment of Mitral Valve Prolapse

Mitral valve prolapse (MVP) is predominantly a benign condition requiring risk stratification based on severity of mitral regurgitation (MR), left ventricular function, and high-risk features, with asymptomatic patients with mild disease needing only surveillance while those with severe MR and symptoms, LV dysfunction, new atrial fibrillation, or pulmonary hypertension should undergo mitral valve repair. 1, 2

Risk Stratification and Initial Assessment

MVP affects 1-2.5% of the population and requires immediate identification of high-risk features that predict complications 2:

• Leaflet thickness ≥5mm is the single most important predictor of complications, associated with increased rates of endocarditis, severe MR, need for valve replacement, and complex ventricular arrhythmias 1, 2
• Bileaflet prolapse, particularly in women with T-wave abnormalities and complex ventricular ectopy, defines a high-risk syndrome for sudden cardiac death 2
• Male gender over 45 years and redundant leaflets with myxomatous degeneration carry higher risk 2

Echocardiography is essential to assess valve morphology, MR severity, and left ventricular size and function using quantitative parameters, with severe primary MR defined as effective regurgitant orifice area ≥0.4 cm² and regurgitant volume ≥60 mL 1, 3

Disease Staging and Management Algorithm

The American College of Cardiology staging system guides treatment decisions 1, 3:

Stage A (Mild MVP, No MR)

• Clinical follow-up every 12 months with echocardiography every 2 years 1, 3
• No medical therapy required 1

Stage B (Progressive MVP, Mild-to-Moderate MR)

• For mild MR: Clinical follow-up every 12 months with echocardiography every 2 years 1
• For moderate MR: Clinical follow-up every 6 months with annual echocardiography 1, 3
• No vasodilators or ACE inhibitors indicated in chronic MR without heart failure 1, 3

Stage C (Severe MR, Asymptomatic)

• Clinical evaluation every 6 months with annual echocardiography 1, 3
• Surgery is indicated when ANY of the following develop 1, 2, 3:
  • Left ventricular ejection fraction <60% 1, 2
  • Left ventricular end-systolic dimension ≥40mm 1, 2
  • New-onset atrial fibrillation 1, 2
  • Pulmonary hypertension 1, 2

Stage D (Severe MR, Symptomatic)

• Immediate surgical referral for all symptomatic patients with chronic severe primary MR and LVEF >30% 1, 2, 3
• Do not delay surgery until symptoms develop or LV dysfunction occurs, as earlier intervention leads to improved survival and functional outcomes 1, 2
• Symptom onset is itself a negative prognostic event even with preserved LV function; symptom improvement with diuretics does not change this prognostic significance 1

Medical Therapy

There is no evidence supporting the use of vasodilators, including ACE inhibitors, in chronic MR without heart failure 1, 3:

• ACE inhibitors should be used only in patients with advanced MR and severe symptoms who are not surgical candidates 1, 2, 3
• Beta-blockers and spironolactone should be considered for standard heart failure management 1, 2
• Beta-blockers are the primary treatment for frequent ventricular extrasystoles (>30/hour), ventricular tachycardia, or ventricular fibrillation 4

Anticoagulation Strategy

Anticoagulant therapy with target INR 2-3 is recommended for patients with permanent or paroxysmal atrial fibrillation, history of systemic embolism, or evidence of left atrial thrombus 1, 2:

• For MVP with atrial fibrillation: Warfarin for patients aged >65 or those with hypertension, MR murmur, or history of heart failure 3
• Aspirin for patients <65 years without MR, hypertension, or heart failure 3
• For MVP with history of stroke: Warfarin for patients with MR, atrial fibrillation, or left atrial thrombus 5, 3
• Aspirin therapy for patients who experience TIAs 5

Surgical Management

Mitral valve repair is strongly preferred over replacement when technically feasible, with superior outcomes at experienced centers 1, 2, 3:

Surgical Indications (Class I)

• Symptomatic patients with severe primary MR and LVEF >30% 1, 2
• Asymptomatic patients with severe MR and LVEF <60% or LVESD ≥40mm 1
• Asymptomatic patients with severe MR and new atrial fibrillation or pulmonary hypertension 1

Surgical Techniques Based on Pathology

Single segment posterior leaflet flail due to fibroelastic deficiency has the highest success rate and should never undergo replacement without attempted repair 2:

• Focal posterior leaflet flail: Focal triangular resection with annuloplasty ring 1, 3
• Anterior leaflet or bileaflet prolapse: Nonresection techniques using PTFE neochord reconstruction or chordal transfer combined with annuloplasty ring 1, 2, 3
• Diffuse posterior leaflet myxomatous disease: Sliding leaflet valvuloplasty with annuloplasty ring 1, 3

Patients with anterior leaflet, bileaflet, or Barlow's disease requiring extensive repair techniques should be preferentially referred to an experienced mitral valve surgeon at a high-volume Heart Valve Center of Excellence 1, 2, 3

Percutaneous Options

• Percutaneous edge-to-edge repair may be considered for patients at high surgical risk 1, 3

Management of Arrhythmic Complications

Sudden cardiac death occurs in 1.4-2.4% of MVP patients, with highest risk in middle-aged women with prior syncope or documented ventricular arrhythmias 2, 4:

• LV fibrosis in papillary muscles and inferobasal wall has been identified in MVP patients with ventricular arrhythmias or sudden death 2, 6
• Infero-lateral ST segment changes and QT prolongation may serve as markers of arrhythmic risk 2
• ICD implantation should be considered for patients presenting with sustained ventricular tachyarrhythmias 2
• Beta-blockers are the primary treatment for frequent ventricular ectopy, bigeminy, runs, polymorphism, or ventricular tachycardia 4

Endocarditis Prophylaxis

Endocarditis prophylaxis is recommended for patients with MVP who have a systolic murmur indicating mitral regurgitation 3, 4:

• Antibiotic prophylaxis prior to dental treatment or surgery is necessary for patients with pan-systolic or end-systolic murmur 4
• Infective endocarditis occurs in 2.9% of MVP cases 4

Critical Pitfalls to Avoid

The presence of moderate or greater residual MR at the time of surgery is the most important predictor of long-term repair failure 1, 2:

• Do not rely on color jet area alone to quantify MR severity, as it can be misleadingly small or large 1
• Avoid single-plane measurements of vena contracta in MVP, as the regurgitant orifice may be non-circular 1
• Echocardiographic assessment can underestimate severity of MR in late-systolic prolapse where regurgitation occurs only in very late systole 1
• Do not delay surgery until symptoms develop, as symptom onset is itself a negative prognostic event 1, 2
• Complex anterior leaflet pathology should not be referred to surgeons without specific mitral valve repair expertise 1
• Valve replacement should not be performed without attempting repair in patients with isolated anterior leaflet prolapse 1