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The mitral valve is one of the heart’s four essential valves, responsible for regulating blood flow between the left atrium and left ventricle. It ensures that oxygen-rich blood moves efficiently in the correct direction, supporting the body’s overall circulation. Mitral valve disease occurs when this valve does not function properly (either becoming narrowed (stenosis), leaky (regurgitation), or structurally abnormal (prolapse). Think of the heart as a two-step pump. The left atrium is the first chamber in that process, it receives fresh, oxygen-rich blood coming back from the lungs. It then passes that blood through the mitral valve into the left ventricle, which is the main pumping chamber. The left ventricle is stronger and more muscular because its job is to push that oxygen-rich blood out to the rest of the body so your organs, muscles, and brain can function properly. When there’s a problem with the mitral valve, this smooth flow gets disrupted. Blood can leak backward or struggle to move forward, causing pressure to build up in the left atrium and then back into the lungs. This can lead to fluid collecting in the lungs (almost like a “traffic jam”) which is why people may feel short of breath or fatigued. At the same time, less blood is effectively pumped out by the left ventricle to the body, meaning tissues don’t get the oxygen and nutrients they need. That’s why symptoms like tiredness, weakness, or dizziness can develop. Early understanding and diagnosis are key to managing mitral valve disease and maintaining long-term heart health.
Doctors assess how serious a mitral valve problem is by combining what they find during a physical examination with detailed imaging of the heart, most commonly an ultrasound scan called an echocardiogram. This scan shows how well the valve is opening and closing, how blood is flowing through the heart, and whether the heart muscle is under strain. In many cases, you may also need a transoesophageal echocardiogram (TOE). This is a specialised scan where a small ultrasound probe is passed gently down the food pipe (oesophagus), which sits directly behind the heart. Because of this close position, it provides much clearer and more detailed images of the valve, helping doctors understand its structure and movement more precisely and plan the best treatment.
The decision to treat a valve problem is based on a combination of how the valve is functioning and how it is affecting the heart and body overall. Research and clinical guidelines show that even before symptoms appear, a leaking or narrowed valve can place extra strain on the heart. Over time, the heart may enlarge or become less efficient, and pressure can build up in the lungs. Doctors therefore look carefully at scan measurements, heart size and function, and any early signs that the condition is beginning to affect the lungs or circulation, not just whether you feel symptoms.
To guide care, valve disease is grouped into four stages. Stage A (at risk) means there are risk factors for valve disease but no significant abnormality yet. Stage B (progressive) refers to mild or moderate disease that requires monitoring over time. Stage C (asymptomatic severe) means the valve problem is severe, even if you feel well, and there may already be early effects on the heart. Stage D (symptomatic severe) is when the condition is advanced and causing symptoms, and treatment is usually recommended. This structured approach helps ensure treatment is timed appropriately—ideally before lasting damage to the heart or lungs develops.
Isolated mitral valve surgery is carried out under general anaesthesia, meaning you will be fully asleep and comfortable throughout the procedure. The operation usually takes around 3–4 hours, and most patients stay in hospital for 5–7 days while they recover. In the traditional approach, the surgeon reaches the heart through the breastbone. This involves making a cut down the centre of the chest to safely access the heart. In some cases, a smaller opening (called a mini-sternotomy) may be used. During the operation, the heart is temporarily slowed or stopped, and a heart-lung machine takes over the job of pumping blood and supplying oxygen to the body. This allows the surgeon to repair or replace the mitral valve in a controlled and safe way. Once the procedure is complete, the heart is restarted, the breastbone is carefully brought back together with strong wires, and the skin is closed with stitches or staples. In many patients, it is possible to perform mitral valve surgery using a minimally invasive (keyhole) approach. Instead of opening the breastbone, the surgeon makes a small cut on the right side of the chest, between the ribs. Special instruments and a camera are used to carry out the operation. In some centres, robot-assisted surgery is available, where the surgeon controls highly precise instruments using a robotic system and a high-definition 3D camera. These minimally invasive techniques can offer important benefits, including smaller scars, less discomfort, a shorter hospital stay, and a quicker return to normal activities. However, they are not suitable for everyone, and the best approach depends on your individual condition and overall health. Your surgeon will discuss the most appropriate and safest option with you. Whichever method is used, your medical team will guide you through the process and support your recovery at every stage.
Concomitant mitral valve surgery means that your mitral valve is treated at the same time as another heart operation. In most cases, this involves repairing the valve, although sometimes a replacement may be needed. For over 90% of patients, this decision is made before the operation and discussed with you in detail so you know what to expect. However, in a small number of cases (around 5–10%), the surgical team may decide during the operation to carry out a mitral valve repair if they believe it will improve how your heart works, reduce risks, and support a better recovery. This decision is made very carefully using detailed imaging during surgery, called transoesophageal echocardiography, and involves close teamwork between the surgeon, anaesthetist, imaging specialist, and often cardiologists. The goal is always to choose the safest and most effective approach for your long-term heart health.
Mitral valve repair is widely recognised as the preferred treatment for many patients with mitral valve disease because it preserves the patient’s natural valve and maintains more normal heart function. Whenever it is technically feasible, repairing the mitral valve is generally recommended over valve replacement. Choosing the right surgeon is a critical part of achieving the best outcome. Patients are strongly advised to seek care from a cardiac surgeon with specialist expertise in mitral valve repair, ideally within a high-volume centre that regularly performs these procedures.
Mitral valve repair offers several important benefits compared with valve replacement. It is associated with improved long-term survival and allows better preservation of the heart’s pumping function. In most cases, patients can avoid the need for lifelong anticoagulation therapy, reducing the risks and lifestyle restrictions associated with long-term blood-thinning medication. Early diagnosis and timely referral for mitral valve repair are key factors in ensuring optimal results. A comprehensive assessment by a specialist heart team helps determine the most appropriate treatment plan for each individual patient. Mitral valve repair involves a range of advanced surgical techniques designed to restore normal valve function and stop leakage. One of the most common causes of severe mitral regurgitation (a leaking mitral valve) is damage to the supporting structures of the valve, known as the chordae (or cords), which help the valve open and close properly.
To treat this condition, surgeons use specialised repair techniques tailored to the patient’s specific valve problem. In many cases, damaged chordae can be replaced with new artificial chords made from Gore-Tex, a durable material that provides long-term support. Alternatively, if part of the valve leaflet is weakened, the surgeon may remove the affected section and carefully reshape and close the remaining tissue to restore normal function.- Once the repair is complete, the mitral valve can close properly again, which stops or significantly reduces the leak and improves the efficiency of the heart. Mitral valve repair is considered the preferred treatment for mitral regurgitation because it preserves the natural valve and is associated with excellent long-term outcomes.
In some patients, mitral valve repair requires more extensive reconstruction to fully restore normal valve function. This is particularly the case when there is significant stretching or weakening of the valve leaflets and the surrounding structures. In these situations, the surgeon may use carefully placed stitches to strengthen and support the valve, ensuring that the leaflets come together properly when the heart beats.
A common issue in mitral valve disease is an enlarged mitral annulus (the ring-like base of the valve). When the annulus becomes stretched or dilated, the valve leaflets can no longer come together properly, leading to leakage (mitral regurgitation). In these situations, repairing the leaflets alone is often not enough, and the size of the annulus must also be corrected. To address this, surgeons implant a specially designed annuloplasty ring around the base of the valve. This ring reduces the size of the enlarged annulus and restores its normal shape, allowing the valve leaflets to close effectively again. The annuloplasty ring acts as a stable frame (similar to a door frame supporting a door) helping the valve function smoothly and reliably over time.
Depending on the complexity of the valve problem, annuloplasty is often combined with other repair techniques. These may include the use of artificial chordae (neochords made from Gore-Tex) to replace damaged supporting structures, and/or resection of excess or overgrown leaflet tissue to reshape the valve and improve leaflet coaptation (closure). By combining these techniques, surgeons can tailor the repair to each patient’s specific anatomy. The result is a durable, long-lasting repair that restores normal valve function, reduces or eliminates leakage, and preserves the patient’s natural heart valve.
There are a variety of biological (tissue) valves that can be used for mitral valve replacement. Most of these valves are made from cow (bovine) or pig (porcine) tissue and are specially treated so they can function safely and effectively inside the human heart. These valves are designed to closely mimic the natural movement of a normal heart valve, allowing blood to flow in a smooth and controlled way. The main advantage of a biological valve is that it is associated with a low risk of blood clot formation. Because of this, most patients do not require lifelong treatment with blood-thinning medication, which can simplify daily life and reduce the need for regular blood tests and monitoring. This makes biological valves an attractive option for many patients, particularly those who may not be suitable for long-term anticoagulation.
The main disadvantage of biological valves is that they are not as durable as mechanical valves. Over time, the valve tissue can gradually wear out, stiffen, or degenerate. This means that the valve may eventually need to be replaced, either with another surgical procedure or, in some cases, a less invasive valve-in-valve treatment depending on individual circumstances.
The durability of a biological valve varies from person to person and is strongly influenced by age. In younger patients, such as children and young adults, the valve may wear out more quickly, sometimes within only a few years. In middle-aged patients, biological valves typically last around 10 to 15 years. In older patients, particularly those over the age of 70, these valves often last significantly longer. As we grow older, our life expectancy becomes shorter, so a valve that lasts for many years is often sufficient for the remainder of life. For this reason, biological valves are frequently a very suitable and practical option for older patients, offering a good balance between safety, convenience, and long-term outcomes.
There are a number of excellent mechanical heart valves available today, and all are designed to perform reliably and safely over the long term. These valves are made from very strong materials, including carbon-coated metal, which allows them to function smoothly within the heart. The main advantage of a mechanical valve is its exceptional durability. Unlike biological (tissue) valves, mechanical valves are designed to last a lifetime and do not wear out over time. This means that, in most cases, patients will not need another valve replacement surgery in the future. For this reason, mechanical valves are more often recommended for younger patients, particularly those under the age of 70.
However, the main disadvantage of mechanical valves is that blood has a tendency to form clots on their surface. If a clot develops on the valve, it can interfere with how the valve opens and closes, which may affect blood flow through the heart. In some cases, a clot can break off and travel to the brain, causing a stroke.
To reduce this risk, patients with mechanical valves must take anticoagulant medication (blood thinners) for life. These medications help prevent clot formation but require regular monitoring to ensure the correct dose is maintained. Taking anticoagulants also slightly increases the risk of bleeding complications, such as bruising or, more rarely, serious bleeding. Even with careful treatment and monitoring, there remains a small but important risk of blood clots and stroke over time. For this reason, choosing a mechanical valve involves balancing the benefit of long-term durability against the need for lifelong medication and follow-up.
Percutaneous Mitral Valve Repair (MitraClip®)
Percutaneous mitral valve repair using the MitraClip® device is a minimally invasive treatment option that can help reduce symptoms and improve quality of life in selected patients. The procedure is usually performed under local anesthesia, meaning recovery is generally quicker than with traditional surgery. During the procedure, a thin, flexible tube (catheter) is guided from a vein in the leg (femoral vein) up to the heart. Using advanced imaging for guidance, the doctor carefully positions and deploys the MitraClip® device on the mitral valve. The clip helps the valve close more effectively by bringing its leaflets together, reducing leakage (regurgitation). After the procedure, patients are monitored in a high-dependency or recovery unit. Most people recover quickly and are able to go home the next day. At present, this treatment is mainly offered to patients who are not suitable candidates for open-heart surgery or who have a higher risk of complications with conventional surgery.
Looking Ahead: Percutaneous Mitral Valve Implantation
In addition to repair techniques, less invasive mitral valve implantation procedures are currently being developed. These approaches aim to streach the existing native mitral valve and implant a new biological valve that has a stent, using catheter-based techniques, without the need for open-heart surgery. While still under clinical evaluation, percutaneous mitral valve implantation may offer another option in the future, particularly for patients who are not eligible for surgery or for whom repair is not suitable. Ongoing research and clinical trials are helping to refine these techniques and determine their long-term safety and effectiveness.
