Mitral Regurgitation
A leaky mitral valve that lets blood flow backward
Quick Facts
- Type: Heart valve condition
- Problem: Mitral valve does not close fully
- Common signs: Breathlessness, fatigue, palpitations
- Often found by: A heart murmur and echocardiogram
Overview
Mitral regurgitation is a condition in which the mitral valve, one of the four valves that control blood flow through the heart, does not close tightly. The mitral valve sits between the left upper chamber (left atrium) and the left lower chamber (left ventricle). Normally it opens to let blood flow forward and closes firmly to stop it from flowing back. When the valve leaks, some blood flows backward into the left atrium each time the heart beats, instead of moving forward to the body.
This backward flow means the heart must work harder to pump enough blood, and over time it can enlarge and weaken. Mitral regurgitation ranges from mild, causing no problems and needing only monitoring, to severe, which can lead to heart failure. It may develop slowly over years or, less commonly, appear suddenly. Many people have no symptoms for a long time, and the leak is often first noticed as a heart murmur during a routine exam. With proper monitoring and treatment, outcomes are usually good.
Symptoms
Many people with mild or even moderate mitral regurgitation have no symptoms for years. When symptoms appear, they often reflect the extra strain on the heart and the backup of blood.
- Shortness of breath, especially with exertion or when lying flat
- Fatigue and reduced ability to exercise
- Heart palpitations or a fluttering, racing heartbeat
- Swelling in the feet, ankles, or legs
- A heart murmur heard by a clinician
Symptoms may worsen gradually as the leak progresses. Sudden, severe mitral regurgitation, which can occur if part of the valve fails abruptly, may cause rapid, severe breathlessness and is a medical emergency.
Causes
Mitral regurgitation can result from problems with the valve itself or from changes in the heart that pull the valve out of shape.
- Mitral valve prolapse: a common cause in which the valve flaps bulge backward and do not seal properly.
- Damage to the valve structures: such as stretched or torn cords that support the valve.
- Heart disease: a heart attack or weakened, enlarged heart muscle can distort the valve.
- Rheumatic heart disease: damage from past rheumatic fever, an important cause in some regions.
- Infection of the valve (endocarditis): which can damage the valve tissue.
Age-related changes to the valve can also contribute, and some causes lead to sudden rather than gradual regurgitation.
Risk Factors
Several factors increase the risk of developing mitral regurgitation.
- A history of mitral valve prolapse
- Previous heart attack or weakened heart muscle
- Untreated high blood pressure over many years
- A history of rheumatic fever or rheumatic heart disease
- Past infection of a heart valve
- Certain congenital (present from birth) heart conditions
- Older age
Diagnosis
Mitral regurgitation is often first suspected when a clinician hears a heart murmur. Tests then confirm the leak and assess its severity and effect on the heart.
- Echocardiogram: the key test, using ultrasound to show the valve, measure the leak, and assess heart size and function. A more detailed view through the esophagus may be used.
- Electrocardiogram (ECG): to check heart rhythm and look for signs of strain.
- Chest X-ray: to view heart size and the lungs.
- Other tests: such as a stress test or cardiac MRI in some cases.
These tests guide whether the regurgitation can be monitored or needs treatment.
Treatment
Treatment depends on how severe the leak is, whether symptoms are present, and how the heart is coping. Mild cases often need only regular monitoring.
- Monitoring: regular checkups and echocardiograms to track the leak and heart function over time.
- Medications: drugs to manage symptoms and related conditions, such as those for heart failure, high blood pressure, or irregular heart rhythms; medicines do not repair the valve but help the heart cope.
- Valve repair: surgery to fix the existing valve, often preferred when feasible.
- Valve replacement: replacing the valve when repair is not possible.
- Minimally invasive procedures: catheter-based options to reduce the leak in selected patients.
The timing of surgery is important and is decided by a heart team based on symptoms and how the heart is affected.
Prevention and Self-Care
- Keep blood pressure under good control
- Attend regular follow-up appointments and echocardiograms as advised
- Treat strep throat promptly to help prevent rheumatic fever
- Maintain good dental and overall hygiene to lower the risk of valve infection
- Take prescribed medicines consistently
- Report new or worsening breathlessness, fatigue, or palpitations promptly
When to See a Doctor
See a clinician if you have unexplained shortness of breath, fatigue, palpitations, or swelling, or if a heart murmur has been found, so the cause can be evaluated. If you already have mitral regurgitation, report any worsening symptoms promptly. Seek emergency care immediately for:
- Sudden, severe shortness of breath or difficulty breathing
- Chest pain or pressure
- Fainting or near-fainting
- A very rapid or irregular heartbeat with dizziness or breathlessness
Sudden severe valve leakage can be life-threatening and requires immediate treatment.
Frequently Asked Questions
What does mitral regurgitation mean?
It means the heart's mitral valve does not close tightly, so some blood leaks backward into the upper chamber instead of moving forward. This makes the heart work harder, and over time a severe leak can strain and weaken the heart.
Do I need surgery for a leaky mitral valve?
Not always. Mild leaks often need only monitoring, while moderate to severe regurgitation with symptoms or effects on the heart may require valve repair or replacement. A heart team decides the best timing based on your tests and symptoms.
Is mitral regurgitation serious?
It can range from harmless to serious. Mild cases may never cause problems, but severe regurgitation can lead to heart failure if untreated. Regular monitoring helps catch worsening early so treatment can be timed appropriately.
What are the warning signs that need urgent care?
Sudden, severe shortness of breath, chest pain, fainting, or a very rapid or irregular heartbeat with dizziness all need emergency care. Sudden severe valve leakage can be life-threatening and requires immediate treatment.
Can mitral regurgitation be prevented?
Some causes can be reduced by controlling blood pressure, treating strep throat to prevent rheumatic fever, and maintaining good hygiene to lower the risk of valve infection. Regular checkups help detect and manage it early.
References
- American Heart Association (AHA). Mitral valve regurgitation.
- Mayo Clinic. Mitral valve regurgitation — Symptoms and causes.
- National Heart, Lung, and Blood Institute (NHLBI). Heart valve diseases.
- MedlinePlus, U.S. National Library of Medicine. Mitral regurgitation.