What Is Tricuspid Regurgitation?

Tricuspid regurgitation (TR) is a condition in which the tricuspid valve—located on the right side of the heart—does not close completely. When this happens, some blood leaks backward each time the heart contracts instead of moving forward toward the lungs.

The tricuspid valve sits between the right atrium (upper chamber) and the right ventricle (lower chamber). Its job is to ensure one-way blood flow into the right ventricle, which then pumps blood to the lungs. When the valve fails to seal properly, backward flow places extra strain on the right side of the heart.

Tricuspid regurgitation ranges from trivial (harmless) to severe, and its impact depends on how much blood is leaking and why the valve is malfunctioning.

How the Tricuspid Valve Normally Works

The tricuspid valve is made up of:

• A strong fibrous ring (the annulus)

• Three flexible leaflets

• Supporting cords that anchor the valve to the heart muscle

When the heart relaxes, the valve opens to allow blood to flow from the right atrium into the right ventricle. When the heart contracts, the leaflets should close tightly to prevent blood from flowing backward.

In tricuspid regurgitation, this closure is incomplete—allowing blood to leak back into the right atrium.

Mild vs Moderate vs Severe Tricuspid Regurgitation

• Trace or trivial TR is extremely common and usually harmless. It causes no symptoms and requires no treatment.

• Mild TR typically has little impact but may be monitored over time.

• Moderate to severe TR is more concerning and can lead to symptoms, heart enlargement, and long-term complications if left untreated.

Types of Tricuspid Regurgitation

There are three main categories:

Primary (Organic) Tricuspid Regurgitation

The valve itself is abnormal or damaged.
Possible causes include:

• Congenital valve abnormalities (such as Ebstein’s anomaly)

• Infection (endocarditis)

• Trauma

• Prior radiation or inflammatory disease

Secondary (Functional) Tricuspid Regurgitation

The valve leaflets are structurally normal, but the heart chambers supporting them are enlarged or distorted.
This is the most common form of clinically significant TR.

Isolated Tricuspid Regurgitation

A subtype of functional TR most often related to:

• Long-standing atrial fibrillation

• Right atrial enlargement

• Prior heart surgery or pacemaker/defibrillator leads
  Importantly, this form occurs without left-sided heart disease or pulmonary hypertension.

What Causes Tricuspid Regurgitation?

Most moderate to severe tricuspid regurgitation develops when the right side of the heart becomes enlarged.

As the right atrium or right ventricle stretches:

• The valve annulus widens (annular dilation)

• Valve leaflets can no longer meet properly

• Supporting structures may become tethered

Common conditions that lead to this include:

• Atrial fibrillation

• Cardiomyopathy

• Pulmonary hypertension

• Left-sided heart disease (such as mitral regurgitation or aortic stenosis)

• Heart failure

Less commonly, the valve itself is directly damaged (primary TR).

Symptoms of Tricuspid Regurgitation

Mild TR causes no symptoms. When regurgitation becomes moderate or severe, symptoms may include:

• Shortness of breath with activity

• Fatigue or reduced stamina

• Swelling in the legs, ankles, or abdomen

• Abdominal fullness or discomfort

Healthcare providers may also detect:

• A heart murmur

• Prominent neck vein pulsations

• Signs of fluid retention

How Echocardiography Diagnoses Tricuspid Regurgitation

Echocardiography is the primary tool used to diagnose and assess tricuspid regurgitation.

An echocardiogram allows providers to:

• Visualize tricuspid valve anatomy and leaflet motion

• Detect backward blood flow using color Doppler

• Assess severity of regurgitation

• Measure right atrial and right ventricular size

• Estimate pulmonary pressures

• Evaluate right ventricular function

Because tricuspid regurgitation often develops as a consequence of other heart conditions, echocardiography also helps identify the underlying cause, not just the leak itself.

Why Early Detection Matters

Tricuspid regurgitation has historically been under-recognized, but we now know that significant TR is associated with worse outcomes when left untreated.

Routine echocardiographic monitoring helps:

• Track progression before symptoms worsen

• Identify when right-sided heart strain is developing

• Guide timing of medical or procedural intervention

The Bottom Line

Tricuspid regurgitation is a common valve condition that ranges from benign to serious. While mild forms are often harmless, moderate to severe TR can place significant strain on the heart and should not be ignored.

Echocardiography plays a central role in diagnosing tricuspid regurgitation, determining its cause, and guiding appropriate management. If you have symptoms of right-sided heart strain or known heart disease, an echocardiogram is often the most important next step.