What does it mean if there is moderate regurgitation of the mitral valve?

It means the mitral valve does not close fully and some blood leaks backwards with each beat, but not enough yet to overload the heart. Most people with moderate regurgitation feel well. It usually needs regular echocardiograms rather than surgery, to check whether the leak or the left ventricle is changing. Your cardiologist will set how often.

How to treat mitral valve regurgitation without surgery?

Mild and moderate regurgitation are usually treated with follow-up echocardiograms and control of blood pressure. Medicines can ease symptoms, for example diuretics for fluid, and treat atrial fibrillation. When the leak comes from a weak ventricle, heart failure medicines may reduce it. In high-risk patients, a catheter device such as MitraClip may be an option. No tablet repairs a degenerative valve.

How serious is a leaky heart valve?

A mildly leaky heart valve is common and often harmless. A severe leak is serious if it is not treated in time. It can enlarge and weaken the heart, cause atrial fibrillation and raise pressure in the lungs. With regular check-ups and surgery at the right moment, most patients do very well. The key is not to miss the window.

What is mitral valve repair surgery?

It is an operation to fix your own mitral valve rather than replace it. The surgeon may reshape a leaflet, replace broken chords with artificial ones and place a ring at the base of the valve. It can be done through the sternum, through a small incision between the ribs, or robotically. When feasible, repair is usually preferred over replacement.

Can mitral regurgitation get worse over time?

Yes, it often does, although usually slowly. A leak can stay stable for years and then increase, or the heart can start to tire even if the leak looks the same. That is why regular echocardiograms are so important, even when you feel well. New breathlessness, palpitations or swelling should prompt an earlier review.

Mitral regurgitation: symptoms, diagnosis and when to operate

Mitral regurgitation explained: causes, symptoms, how it is diagnosed, when surgery is needed, and why repairing the valve is usually better than replacing it.

Some heart conditions progress silently for years. Mitral regurgitation is one of them.

Many patients come to the clinic with a diagnosis they have had for some time, sometimes for years, without fully understanding what it means, how serious it is, or when the moment will come to do something about it. This guide is for them, and for their families.

What is the mitral valve?

The heart has four valves that work like gates, controlling the flow of blood between its chambers and out to the rest of the body. The mitral valve sits between the left atrium and the left ventricle, the two chambers on the left side of the heart that pump oxygen-rich blood to the whole body.

It has two leaflets that open to let blood pass from the atrium into the ventricle, and close tightly when the ventricle contracts, so that blood goes forward into the aorta instead of back the way it came.

What is mitral regurgitation?

Mitral regurgitation, also called mitral insufficiency, means the valve does not seal completely. With every heartbeat, part of the blood that should move forward leaks back into the left atrium. That backward flow is not harmless. Over time it causes two problems:

Overload of the left heart. The left ventricle has to pump extra blood to make up for what leaks back. Working above its normal capacity year after year, it dilates and weakens, and if it is left too long the damage can become irreversible.
Higher pressure in the lungs. The blood pushed back into the atrium raises the pressure there, and that pressure is passed on to the veins of the lungs. Fluid builds up, which is why so many patients feel short of breath.

What causes it?

Degenerative disease (mitral valve prolapse). The most common cause in many countries. The leaflets become redundant or the cords that hold them stretch or break, and part of the valve falls back into the atrium as it closes, like a door that no longer fits its frame. See mitral valve prolapse.
Rheumatic disease. The after-effect of rheumatic fever, an untreated streptococcal infection that damages the heart valves. It is still common in Mexico and Latin America.
Ischaemic disease. A previous heart attack damages the muscle that anchors the valve to the ventricle.
Functional regurgitation. The ventricle dilates for another reason, and leaflets that are anatomically normal are pulled apart so they can no longer meet.
Endocarditis. Infection of the valve, which can destroy the leaflets or the structures that support them.

A related condition, mitral stenosis, is the opposite problem: the leaflets thicken and fuse, and the valve does not open enough. It is usually rheumatic in origin and is assessed in the same way.

What are the symptoms?

This is the difficult part: for years, sometimes decades, mitral regurgitation may cause no symptoms at all. The heart is remarkably adaptable and compensates for the extra work for a long time. When that compensation runs out, symptoms appear:

Shortness of breath, first on exertion, then at rest or when lying flat
Tiredness and fatigue without an obvious cause
Palpitations, especially if atrial fibrillation develops
Swelling of the legs or abdomen
Activities that used to be easy becoming hard work

By the time these symptoms appear, the heart has usually been overworking for a while. That is why regular echocardiograms matter, even when you feel well.

How is it diagnosed?

Transthoracic echocardiogram

The essential test. An ultrasound of the heart, done from the outside of the chest, shows the anatomy of the valve, measures how much it leaks, assesses the function of the left ventricle and detects the early changes that tell us the valve is starting to affect the heart. It is also the test we use for follow-up. See echocardiogram.

Transoesophageal echocardiogram

When we need more detail, especially to plan a repair, this test gives a very precise three-dimensional image of the valve. A thin probe is passed through the mouth into the oesophagus, which lies just behind the heart. It is done with light sedation and you go home the same day. See transoesophageal echocardiogram.

Cardiac MRI

In selected cases it adds information about the function of the ventricle and the severity of the leak.

Cardiac catheterisation

Not always needed for the valve itself, but often done before surgery to rule out coronary artery disease, particularly in older patients.

When is it time to operate?

This is the question I am asked most often, and the one that most needs an individual answer. Not every case needs surgery. Mild and moderate regurgitation often only needs periodic follow-up. But there are clear signs that it is time to act:

Symptoms. When breathlessness, fatigue or reduced exercise tolerance can be attributed to the valve.
Changes in the left ventricle. Even without symptoms, when the echocardiogram shows the ventricle starting to dilate or weaken (the international guidelines use an ejection fraction of 60% or lower, or an end-systolic diameter of about 40 mm or more, as markers), it is time to act before the damage becomes permanent.
Severe regurgitation with anatomy that can be repaired. For severe prolapse that can be repaired durably, the guidelines increasingly support surgery before symptoms appear, in centres with good repair results. Waiting too long can compromise the outcome.
New atrial fibrillation or raised pressure in the lungs. Both are signs that the valve is starting to take its toll, and atrial fibrillation is harder to reverse once it is established.

Repair or replace: the most important decision

Once surgery is decided, one question shapes the long-term result more than any other: do we repair the valve, or replace it? My position is clear. I prefer repair whenever the conditions allow it. Compared with a prosthesis, a successful repair of a degenerative mitral valve offers:

Better long-term survival
Better preservation of the function of the left ventricle, because the valve’s own structure and supports are kept
No need for lifelong anticoagulation, as there is with a mechanical valve
No built-in expiry date, as there is with a biological valve, which typically lasts 10 to 20 years

There is one condition I always explain to my patients: a repair only makes sense if it has a very high probability of lasting. If the anatomy does not allow that, because of extensive calcification, severe damage or an unfavourable shape, then a well-done replacement is better than a repair that will fail in five years. Making that call takes experience and a detailed transoesophageal echocardiogram before surgery. In experienced centres, most degenerative mitral valves can be repaired.

How is the valve repaired?

Repair techniques have evolved enormously over the past thirty years. Depending on the cause and the anatomy, we combine:

Leaflet resection: removing a prolapsing segment and reconstructing the leaflet.
Artificial chords (neochordae): replacing broken or stretched chords with very durable synthetic sutures.
Annuloplasty: a ring placed at the base of the valve to restore its shape and reinforce the repair. It is part of almost every mitral repair.

How the surgery is done

Repairing the mitral valve does not always mean opening the sternum. Depending on your case, there are three ways to reach the valve:

Minimally invasive surgery: through an incision of about 5 cm between the ribs, without cutting the sternum. Recovery is usually faster than with open surgery. See minimally invasive cardiac surgery.
Robotic surgery: through a few small incisions between the ribs, with the Da Vinci system and a magnified three-dimensional view. Dr. Alejandro Molina performed the first robotic mitral valve repair in the Ángeles Health System; you can read about that case and about robotic heart surgery in general.
Conventional surgery: for complex cases, reoperations, or when the anatomy does not suit a less invasive route. It remains an excellent operation with proven results.

If you are weighing the three, our guide to robotic, minimally invasive or open-chest surgery explains how we choose.

What about MitraClip?

MitraClip is a device placed through a catheter, without surgery, to reduce the leak. It is a valuable option, and I want to be honest about its role in our practice: we do not consider it an alternative to surgery for patients who are good surgical candidates. It is meant for older patients, patients at high surgical risk, patients with a very weak ventricle, or anatomy that cannot be repaired. For a young or middle-aged patient in good health, surgical repair offers long-term results that MitraClip cannot match. We explain why in MitraClip: what it is and who it is really for.

The most important message

Mitral regurgitation progresses slowly, but if it is not treated at the right time it can cause permanent damage to the heart. Regular echocardiograms are essential, even when you feel well. And when the time comes to operate, the decision about how to do it deserves a complete assessment by a team that offers every option, which is what we mean by a Heart Team.

If you have mitral regurgitation and want to know what stage you are at, whether it is time to act, and which approach suits your case, bring your studies to a consultation, in person in Guadalajara, Querétaro or Hermosillo, or by video from anywhere.

About the author

Dr. Alejandro Molina Romo is a cardiovascular surgeon practising in Guadalajara, Querétaro and Hermosillo. He trained in cardiothoracic surgery at the Universidad de Guadalajara, completed advanced training in cardiac surgery, minimally invasive surgery, robotic surgery and structural interventions at the University of Montreal, and a fellowship in structural cardiology and TAVI at CHU Bordeaux, France. He performed the first robotic mitral valve repair in the Ángeles Health System and the first robotic heart surgery in Guadalajara.

Medical degree: Universidad Autónoma de Guadalajara, Cédula Profesional 5757260 · Cardiothoracic surgery: Universidad de Guadalajara, Cédula de Especialidad 10768871 · Current certification, Consejo Nacional de Cirugía del Tórax, no. 447

This content is educational and does not constitute personal medical advice. Every cardiac case is unique and requires individual assessment by a specialist medical team. The results described come from published studies and do not guarantee outcomes in any individual case. Always consult the doctor treating you before making decisions about your treatment, especially if you take anticoagulants, antiplatelet drugs or other cardiac medicines.