Mitral valve replacement is performed by removing a damaged or diseased mitral valve and stitching a prosthetic valve in its place. The surgery can be done through traditional open-heart surgery, minimally invasive techniques, or in some cases a catheter-based procedure that avoids chest incisions entirely. Which approach your surgeon recommends depends on your anatomy, overall health, and the specific problem with your valve.
Why a Mitral Valve Gets Replaced
The mitral valve sits between the two left chambers of your heart, opening and closing with each heartbeat to keep blood flowing in one direction. When it leaks significantly (regurgitation) or becomes too narrow (stenosis), the heart has to work harder to compensate. Over time, this extra workload weakens the heart muscle and can lead to heart failure, irregular heart rhythms, or fluid buildup in the lungs.
Surgeons generally prefer to repair the mitral valve rather than replace it when possible. Replacement becomes the recommendation when the valve is too damaged or calcified for a successful repair, when prior repair attempts have failed, or when the valve structure makes a durable repair unlikely. Emergency replacement is sometimes necessary after a heart attack damages the muscles anchoring the valve, which can cause sudden, life-threatening leakage.
Tests Before Surgery
An echocardiogram is the primary tool for evaluating the mitral valve. This ultrasound of the heart shows how severely the valve is leaking or narrowed, how well the heart muscle is pumping, and whether the chambers have enlarged from the extra strain. It also reveals structural details like thickened or calcified leaflets and problems with the tissue anchoring the valve in place.
A cardiac CT scan may be ordered to get a more detailed three-dimensional view of the valve anatomy and to check the coronary arteries for blockages. If significant blockages are found, bypass grafting can sometimes be performed during the same operation. These imaging results also help the surgical team select the right size of prosthetic valve.
Traditional Open-Heart Surgery
The most established approach uses a median sternotomy, a vertical incision down the center of the chest that splits the breastbone. Once the sternum is divided, the surgeon opens the pericardium (the sac surrounding the heart) and connects the patient to a heart-lung bypass machine, which takes over the job of circulating and oxygenating blood. The heart is then stopped using a cold solution called cardioplegia, giving the surgeon a still, bloodless field to work in.
With the heart stopped, the surgeon opens the left atrium to access the mitral valve. Before touching the valve, the left atrial appendage is inspected for blood clots, which are common in patients with longstanding valve disease. The diseased valve leaflets are then cut away, and the fibrous ring where the valve sat (the annulus) is prepared to anchor the new prosthetic valve. The replacement valve is sewn into the annulus with a ring of sutures, tested for proper seating and function, and the left atrium is closed. The heart is then restarted, the patient is weaned off the bypass machine, and the breastbone is wired back together.
Minimally Invasive Approaches
Several techniques avoid splitting the entire breastbone. A right mini-thoracotomy uses a smaller incision between the ribs on the right side of the chest, typically through the fourth rib space. A partial sternal split divides only part of the breastbone in a J-shape. Both approaches accomplish the same valve replacement but through a smaller window, using specialized long-handled instruments and a camera for visualization.
Robotic-assisted surgery takes this further, using multiple incisions no larger than 1.5 centimeters for the robotic instrument arms. The surgeon controls the instruments from a console while viewing the heart through a magnified 3D display. Because these smaller incisions can’t accommodate the standard tubing for the heart-lung machine, blood is typically rerouted through vessels in the groin instead of the chest.
Minimally invasive techniques generally mean less blood loss, less pain, and a faster return to normal activity. Not every patient is a candidate, though. Previous chest surgery, certain body types, or complex valve anatomy may make the traditional approach safer.
Catheter-Based Replacement
Transcatheter mitral valve replacement is a newer option primarily reserved for patients who are too high-risk for open surgery. A catheter is inserted through a blood vessel in the leg or through a small opening in the chest and threaded up to the heart. A compressed replacement valve rides inside the catheter and, once positioned within the old mitral valve, a balloon expands it into place. No heart-lung machine is needed, and the heart keeps beating throughout. This technology is still evolving, and it remains less widely available than surgical options.
Mechanical vs. Biological Valves
The choice of prosthetic valve is one of the most consequential decisions in the process, because it shapes your daily life for years afterward.
Mechanical valves are made from durable synthetic materials like carbon and titanium. They last 20 to 30 years, and many outlast the patient. The tradeoff is that blood tends to clot on artificial surfaces, so you’ll need to take the blood thinner warfarin for the rest of your life. This means regular blood tests to keep your clotting level (measured as INR) in a target range of 2.5 to 3.5 for a mitral position, along with a low dose of aspirin. Living on warfarin requires dietary consistency, careful management of other medications, and awareness that injuries carry a higher bleeding risk.
Biological valves are made from animal tissue, usually from pig heart valves or cow heart lining, mounted on a frame. They don’t require lifelong blood thinners, which makes daily life simpler. The downside is durability: biological valves typically last 10 to 15 years, with structural wear beginning around five years after implantation. That means a younger patient may eventually need a second valve replacement.
The general guideline is that patients younger than 60 to 65 receive mechanical valves to avoid the likelihood of reoperation, while patients older than 60 to 65 receive biological valves to avoid the burden and risks of lifelong anticoagulation. But this is a personal decision shaped by your lifestyle, your comfort with blood-thinning medication, and your individual risk profile.
Recovery After Surgery
After open-heart surgery, you’ll spend one to two days in the intensive care unit, where the team monitors your heart rhythm, blood pressure, breathing, and drainage from the chest. Once stable, you’ll move to a regular hospital room for several more days. Most people spend about a week in the hospital total.
If your breastbone was split, it takes six to eight weeks to heal fully. During that time, you’ll need to avoid lifting anything heavy, pushing or pulling with your arms, and driving. Most people start a cardiac rehabilitation program within a few weeks of discharge, which involves supervised exercise that gradually increases in intensity. Many patients return to normal daily activities within two to three months, though full stamina can take longer to rebuild. Recovery from minimally invasive or robotic surgery is generally faster because the chest wall sustains less trauma.
Risks and Long-Term Complications
Operative mortality for isolated mitral valve replacement is low at experienced centers. Cleveland Clinic reported a 1.1% operative mortality rate across 181 isolated mitral valve replacements in 2024, well below the 3.4% national predicted rate. Combined with coronary bypass, their mortality rate was even lower. These numbers reflect a high-volume center, so outcomes vary by institution.
The main long-term complications relate to the prosthetic valve itself. Blood clots can form on mechanical valves even with proper anticoagulation, causing stroke or valve obstruction at a rate of roughly 1% per year. Bleeding events from the blood thinners occur at about 0.5% per year. Infection of the prosthetic valve (endocarditis) is rare, around 0.5% per year, but serious when it occurs and sometimes requires reoperation. Paravalvular leaks, where blood seeps around the edges of the sewn-in valve, can develop if sutures loosen or if the tissue around the valve ring is heavily calcified. Tissue overgrowth near the valve (pannus) can also gradually restrict the valve’s movement over time.
For biological valves, structural deterioration is the primary concern. As the tissue gradually stiffens and calcifies, the valve may begin to leak or narrow again. Monitoring with regular echocardiograms allows your cardiology team to track valve function and plan for reintervention before symptoms become severe.