Mitral Valve Disease

The Mitral Valve

The mitral valve is one of four heart valves that control the flow of blood in and out of the heart. The mitral valve separates the upper left heart chamber (left atrium) from the lower left heart chamber (left ventricle). The mitral valve has two leaflets, which open and close to allow blood flow into the left ventricle without leaking back into the left atrium.

What is Mitral Regurgitation?

If the mitral valve becomes abnormally leaky (mitral regurgitation), blood flows into the left atrium and can increase pressure within the lungs. This can lead to breathlessness and eventually to signs and symptoms of heart failure. As the heart works harder to pump blood to the body to compensate for the blood that flows backwards through the valve, the main pump (the left ventricle) can tire, enlarge and consequently struggle to pump effectively. 

Mitral regurgitation is the second most common indication for valvular surgery in Europe. Anatomically, the type of regurgitation (leak) can be divided into two groups; functional and degenerative.

Symptoms of Mitral Regurgitation

Some patients are unaware of their valvular disease and are only diagnosed incidentally. Others may find they have mitral valve disease for many years and do not have any symptoms until something in the heart changes as the heart dilates and grows tired as it compensates for the leaking valve.
Those with symptoms most commonly experience:

    • Irregular heartbeat (arrhythmia)
    • Shortness of breath (dyspnoea), especially on exertion or when lying down 
    • Sensation of a rapid, pounding or fluttering heartbeat (palpitations)
    • Swollen feet or ankles (oedema)
    • Tiredness
    • Reduction in exercise capacity

 

If you develop symptoms that suggest mitral valve regurgitation or another problem with your heart, see your health care provider right away.

If you have a heart murmur, you may be referred to a doctor that specializes in heart valve diseases (cardiologist/cardiac surgeon).

What happens without treatment?

What if I leave the mitral leak untreated?

As mitral valve regurgitation gets worse, the heart must work harder to pump blood to the body. The strain on the heart can cause the left lower chamber to enlarge. The heart muscle may become weak. Potential complications of severe mitral valve regurgitation include:

Irregular and often rapid heart rate (atrial fibrillation). Increased size of the upper left heart chamber (atrium) caused by mitral valve regurgitation may trigger this common heart rhythm disorder. Atrial fibrillation has been linked to an increased risk of blood clots and stroke.

High blood pressure in the lungs (pulmonary hypertension). Long-term untreated or improperly treated mitral regurgitation can increase pressure in the blood vessels in the lungs. As pressure rises, fluid builds up in the lungs.

Congestive heart failure. In severe mitral valve regurgitation, the heart has to work harder to pump enough blood to the body. The extra effort causes the left lower heart chamber (ventricle) to get bigger. Untreated, the heart muscle becomes weak. This can cause heart failure and even death.

Causes

  • Mitral valve prolapse
  • Rheumatic fever
  • Heart attack (Ischaemic mitral regurgitation
  • Heart problem present at birth (congenital heart defect)
  • Thickening of the heart muscle (cardiomyopathy)
  • Damaged tissue cords
  • Endocarditis
  • Chronic Atrial Fibrillation
  • Mitral annular disjunction
  • Mitral annular calcification


    Without treatment, mitral regurgitation usually gets worse with time. Although medicines can improve some of the symptoms, for example shortness of breath and swelling, the effects of long-term mitral regurgitation can result in symptoms and signs of heart failure (breathlessness, fatigue, fluid over-load) even with medical treatment. If left untreated, the pumping chambers can begin to fail, something that may become irreversible. 

    Current evidence suggests the mortality for untreated mitral regurgitation is approximately two years.

What is Mitral Stenosis?

Mitral valve stenosis is a narrowing of the heart's mitral valve. The abnormal valve does not open properly, blocking blood flow into the main pumping chamber of your heart (left ventricle). Mitral stenosis can make you tired and short of breath, among other problems.

The main cause of mitral stenosis is related to healed rheumatic fever infection, which is related to streptococcal infections. Rheumatic fever — now rare in the United Kingdom, but still common in developing countries — can scar the mitral valve. Left untreated, mitral valve stenosis can lead to serious heart complications. Mitral stenosis can also occur with advancing age and many years after radiotherapy to the chest.

Symptoms

In mitral stenosis, pressure increases in the heart which is transmitted to the lungs, resulting in fluid build-up (congestion) and shortness of breath.

The condition usually progresses slowly over time. You may feel fine with mitral stenosis, or you may have mild symptoms for decades.

Signs and symptoms of mitral valve stenosis include:
- Shortness of breath, especially with activity or when you lie down
- Fatigue, especially during increased activity
- Swollen feet or legs
- Sensations of a rapid, fluttering heartbeat (palpitations)
- Chest discomfort or chest pain
- Coughing up blood
- Dizziness or fainting
- Heart murmur
- Fluid build-up in the lungs (pulmonary oedema or pleural effusion)
- Irregular heart rhythms (arrhythmias e.g. atrial fibrillation)

Mitral stenosis symptoms may appear or worsen when your heart rate increases, such as during exercise. They may also be triggered by pregnancy or other conditions that cause stress on the body, such as an infection. The increased heart rate associated with arrhythmia, such as atrial fibrillation, can also worsen symptoms.

Causes

Rheumatic heart disease - A complication of a streptococcal throat infection, rheumatic fever can damage the mitral valve. Rheumatic heart disease is the most common cause of mitral stenosis. It can damage the mitral valve by causing the leaflets to thicken or fuse. Signs and symptoms of mitral valve stenosis might not be obvious up for years.

Calcium deposits - As you age, calcium deposits can build up around the mitral valve (annulus), which can occasionally cause mitral stenosis. This can also occur in relation to kidney failure.

Radiation therapy - Treatment for certain types of cancer that requires radiation to your chest area can sometimes cause the mitral valve to thicken and harden. This is less common with more modern forms of radiotherapy.

Other causes - In rare cases, babies are born with a narrowed mitral valve (congenital defect) that causes problems over time. Some autoimmune diseases, such as lupus (SLE), also may rarely cause mitral valve stenosis.

Treatment

Surgery

Surgery remains the gold standard treatment with mitral valve replacement. Options include:

- Biological valve: Durability approximately 10-12 years (does not require a blood thinner for the valve alone)

- Mechanical valve : Durability 30 years - lifelong (anticoagulation with warfarin required)

Balloon Valvuloplasty (Percutaneous transcatheter mitral commissurotomy, PTMC)

In very specific cases, balloon valvuloplasty can be a very good treatment for mitral stenosis. This technique is an option for mitral stenosis caused by rheumatic heart disease where the corners of the mitral valve tend to become fused together. PTMC is usually carried out under a general anaesthetic and can be a low risk alternative to surgery.

Medical therapy

In certain situations, the symptoms of mitral stenosis can be controlled with medication over many years.

Our Team

Toufan Bahrami

Mr Toufan Bahrami is a senior consultant in cardiac surgery , working at both Royal Brompton and Harefield Hospital, where he treats both NHS and private patients.

He also works at The Harley street clinic in central London .With more than 4000 cardiac operations of which 1500 are minimally invasive procedures over past 21 years, He is the   only consultant in UK expert in all aspects of minimally invasive cardiac surgery including , Mitral , Aortic valve and root and CABG with a longstanding track record.

Saeed Mirsadraee

Dr Mirsadraee’s specialist interest is cardiovascular imaging and in particular imaging of the heart valves, surgical and transcatheter aortic and mitral valve procedure planning, and complex aortic conditions. He is the radiology lead for aortic and mitral imaging at the Royal Brompton and Harefield hospitals. Dr Mirsadraee uses CT images in planning Mitral valve procedures such as minimal access mitral valve surgery, transcatheter mitral valve implantation (eg. Tendyne, Sapien in ring/MAC), cord and left ventricular remodelling procedures (eg. Accucinch, Neocord).

Ali Vazir

Dr Ali Vazir is a consultant cardiologist based at the Royal Brompton and Harefield Hospitals, part of Guy’s and St Thomas’ NHS Foundation Trust. He is also an Honorary Clinical Senior Lecturer at National Heart and Lung Institute, Imperial College London. 

He is an expert in heart failure and echocardiography. He is the clinical lead for heart failure at the Royal Brompton Hospital. He trained in London and was a Post-doctoral research fellow at the Brigham and Women’s Hospital and Harvard Medical School, Boston, USA. He is a principal investigator for several multicenter trials. 

Lauren Connolly

Lauren has worked within the cardiology and cardiac surgery care setting for seven years. In recent years she has worked within the structural heart team as clinical nurse specialist and co-ordinator for the trans catheter team, specifically focusing in mitral and tricuspid valve disease.

Dr Robert Smith

Dr Smith’s specialist interest is Mitral valve disease and interventions. He leads one of the largest structural heart disease programmes in Europe at the world renowned Royal Brompton & Harefield Hospitals. It is also the first centre of excellence for MitraClip in the world.