What do the heart's tricuspid and bicuspid valves do?

The following table shows the different roles the tricuspid and bicuspid valves have:

The four heart valves open to allow blood to flow into and away from the heart and close to prevent blood from flowing back.

The valves allow the heart to receive blood from the body and pump it to the lungs to oxygenate it. It then pumps the oxygen-rich blood back out of the body.

These valves need to open and close fully and easily with each heartbeat to work properly. Issues with the heart valves can interfere with this function.

Heart valve disease can cause regurgitation, in which a valve does not close completely, and blood can leak backward in the direction it came from.

Heart valves also need to open properly. Aortic stenosis refers to the narrowing and stiffening of the heart valve. This means it cannot open as widely as it should to allow blood to pass through, which restricts the blood flow.

All valves need the right number of cusps to work properly, but sometimes, a cusp may be missing. If the heart cannot pump blood as effectively as it should, it can lead to serious complications, such as heart failure or sudden cardiac arrest.

Learn more about aortic stenosis.

Tricuspid valve

The tricuspid valve opens to let blood flow from the right atrium to the right ventricle. It closes to prevent blood from flowing from the right ventricle toward the right atrium.

Bicuspid or mitral valve

The bicuspid valve opens to let blood flow from the left atrium to the left ventricle. It closes to prevent blood from flowing from the left ventricle back toward the left atrium.

The bicuspid valve has two cusps, while the other valves have three. Another name for the bicuspid valve is the mitral valve.

Pulmonary valve

The pulmonary valve sits between the right ventricle and the pulmonary artery.

This valve opens to let blood pass from the right ventricle through the pulmonary artery to the lungs to oxygenate the blood.

The pulmonary valve closes to prevent blood from flowing back from the pulmonary artery to the right ventricle.

Aortic valve

The aortic valve sits between the left ventricle and the aorta, which is the major artery carrying oxygenated blood from the heart to the rest of the body.

This valve opens to let blood flow from the left ventricle to the aorta and closes to prevent blood from flowing back to the left ventricle.

Learn more about heart valves.

The below conditions can affect the tricuspid valve.

Tricuspid atresia

Tricuspid atresia means the heart does not have a tricuspid valve, which means blood cannot flow properly between the right atrium and the right ventricle. People with this condition may have too much or too little blood flow to the lungs.

Treatment for tricuspid atresia may include using a stent to increase blood flow to the lungs, or banding, which narrows the pulmonary artery to decrease blood flow to the lungs.

Tricuspid regurgitation

Tricuspid regurgitation occurs if the tricuspid valve leaks blood back toward the right atrium. Increased blood flow to the right atrium can cause it to enlarge and alter the pressure in the heart.

Treatment may include treating the underlying cause and repairing or replacing the atypical valve.

Tricuspid stenosis

With tricuspid stenosis, the opening of the tricuspid valve narrows and restricts blood flow to the right ventricle. This can negatively affect blood pressure and blood flow in the heart.

Treatment may include regular monitoring of the heart, medications, or surgery to repair or replace the tricuspid valve.

The following conditions can affect the bicuspid or mitral valve:

Mitral valve prolapse

Mitral valve prolapse occurs if the cusps of the bicuspid valve do not close properly and bulge into the left atrium. For severe cases, treatment may include valve repair or replacement.

Mitral valve regurgitation

Mitral valve regurgitation occurs if the bicuspid valve leaks blood back toward the left atrium.

Treatment may include blood thinning medication or surgery to repair or replace the valve.

Mitral valve stenosis

Mitral valve stenosis occurs if the bicuspid valve’s opening narrows, restricting blood flow to the left ventricle.

Treatment may include medications to treat symptoms and prevent blood clots or surgery to repair or replace the valve.

Learn more about common heart valve disorders.

Heart valves allow blood to flow into the heart, through the chambers, and out to the rest of the body. They also prevent blood from flowing back the wrong way.

The tricuspid valve allows blood flow between the right atrium and the right ventricle. The bicuspid valve allows blood flow between the left atrium and the left ventricle.

Common heart valve disorders include stenosis and regurgitation, which doctors may treat with medication or surgery.