What is tricuspid regurgitation?

Tricuspid regurgitation is a leaky tricuspid valve. The tricuspid valve sits between the right atrium and right ventricle, and normally prevents blood flowing backwards when the right ventricle contracts. In tricuspid regurgitation the valve does not close properly, so blood leaks backwards into the right atrium and the venous system, allowing pressure to build up in the body’s veins.

What causes tricuspid regurgitation?

There are many causes. The most common is secondary (or functional) tricuspid regurgitation — the valve itself is not directly diseased, but stretches because of an enlarged right ventricle, an enlarged right atrium, or persistent atrial fibrillation. Primary tricuspid regurgitation, where the valve leaflets themselves are abnormal, is less common and includes causes such as previous endocarditis, rheumatic disease, congenital abnormalities, or damage from pacemaker or defibrillator leads. Severe tricuspid regurgitation is increasingly recognised in older patients, particularly those with atrial fibrillation or long-standing left-sided heart disease.

What are the symptoms?

Mild tricuspid regurgitation rarely causes symptoms. As the leak becomes more severe, patients may develop:

• Breathlessness on exertion
• Fatigue and reduced exercise tolerance
• Swelling of the ankles and legs (peripheral oedema)
• Abdominal swelling and discomfort (ascites)
• Liver congestion, sometimes with abnormal liver tests
• Worsening of pre-existing atrial fibrillation

How is tricuspid regurgitation diagnosed?

The diagnosis is usually made on a transthoracic echocardiogram (TTE). The severity is graded as mild, moderate, severe or torrential, based on the volume of blood leaking back across the valve. Where treatment is being considered, additional tests are usually arranged — a transoesophageal echocardiogram (TOE) for detailed valve anatomy, and sometimes a cardiac CT or MRI to assess the right heart chambers and plan procedural options.

What are the treatment options?

Mild and moderate tricuspid regurgitation usually do not need specific treatment beyond managing any underlying cause (for example controlling atrial fibrillation) and using diuretics if there is fluid retention.

For symptomatic severe tricuspid regurgitation, options include:

• Transcatheter tricuspid edge-to-edge repair (TEER) — clipping the valve leaflets together using the Pascal or TriClip system, without open-heart surgery.
• Transcatheter tricuspid valve replacement with Evoque — minimally invasive valve replacement, for selected patients where TEER is not the right option.
• Caval valve implantation with TricValve — for patients unsuitable for TEER or direct replacement, where venous congestion is the dominant problem.
• Open heart surgery — tricuspid repair or replacement, for selected patients at acceptable surgical risk.
• Medical therapy alone — for patients in whom intervention is not appropriate.

The right choice depends on the underlying cause, the severity of the leak, the function of the right ventricle, surgical risk, and the dominant symptoms. The decision is always made in a structural valve multidisciplinary team meeting.