Mitral valve regurgitation
Also called: Mitral insufficiency, MR, Mitral valve prolapse
The mitral valve does not close properly, so blood leaks backwards into the left atrium with each heartbeat. Mild leaks are common and harmless; severe leaks enlarge the heart and cause breathlessness.
Condition-specific references are below. Individual claims and this page have not been clinically reviewed. Read about this content.
Moderate or severe MR affects about 2% of the population, more in older people.
What happens in the body
Primary MR results from damage to the valve itself (prolapse, torn chords); secondary MR results from a dilated left ventricle pulling the leaflets apart.
Causes
- Mitral valve prolapse (myxomatous degeneration)
- Ruptured chordae tendineae
- Dilated left ventricle from heart failure or heart attack
- Rheumatic heart disease
- Infective endocarditis
Risk factors
- Age
- Previous heart attack
- Connective tissue disorders (Marfan syndrome)
- Rheumatic fever
Symptoms
- Breathlessness
- Fatigue
- Palpitations (often from atrial fibrillation)
- Swollen ankles
- None when mild
Diagnosis — tests and examinations
- Pansystolic murmur at the apex
- Echocardiography (transthoracic, transoesophageal)
- Cardiac MRI to quantify
- ECG for atrial fibrillation
Treatment
Medicines and medical treatment
- Heart failure medicines for secondary MR
- Anticoagulation if atrial fibrillation develops
Operations and procedures
- Surgical mitral valve repair (preferred) or replacement
- Transcatheter edge-to-edge repair (MitraClip) for high-risk patients
Self-care, home remedies and lifestyle
- Regular follow-up scans
- Good dental hygiene
- Report increasing breathlessness
Possible complications
- Heart failure
- Atrial fibrillation and stroke
- Pulmonary hypertension
- Endocarditis
Prevention
- Prompt treatment of heart attacks and heart failure; antibiotic treatment of strep throat prevents rheumatic disease
Outlook
Excellent after timely repair of primary MR; secondary MR reflects the underlying heart muscle disease.
When to see a doctor
See a doctor for new breathlessness, palpitations or a murmur found at a check-up.
Sources and further reading
These sources cover this condition. They have not been checked against every statement on this page.
Related conditions
Educational overview, not medical advice. Treatment varies by person and location. Consult a qualified health professional for diagnosis or care. Read our content and model notes and privacy information.