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Double Inlet Left Ventricle (DILV) in Children

The heart has four chambers. In DILV, both upper chambers send blood into the left ventricle. The right ventricle is usually very small or not fully developed.

This affects how blood flows through the heart and how oxygen reaches the body. Because only one ventricle does most of the work, DILV is called a single-ventricle heart defect.

Early diagnosis and specialized heart care help children get the treatment they need.

How the Heart Normally Works

The heart is a pump that moves blood through the body. It has four chambers:

• Two atria (upper chambers)
• Two ventricles (lower chambers)

The right side of the heart pumps oxygen-poor blood to the lungs. In the lungs, blood picks up oxygen. The left side of the heart pumps oxygen-rich blood to the rest of the body.

The ventricles keep oxygen-poor and oxygen-rich blood separate. This separation helps the body get the oxygen it needs to grow and stay healthy.

What Happens in Double Inlet Left Ventricle?

In DILV, both atria send blood mainly into the left ventricle. The right ventricle is often very small. It may not be able to pump blood normally.

Because of the DILV heart structure:

• Oxygen-rich blood and oxygen-poor blood mix together.
• The single working ventricle pumps blood to both the lungs and the body.
• Single-ventricle circulation is less efficient than in a normal heart.

Children with DILV may have lower oxygen levels in their blood. This can lead to symptoms such as bluish skin or breathing problems.

What Causes Double Inlet Left Ventricle?

DILV develops early during pregnancy when the baby’s heart is forming. In most cases, the exact cause is unknown.

Some congenital heart defects happen because of changes in genes or problems during early heart development. During the first eight weeks of pregnancy, the heart forms from a simple tube that must fold, divide and separate into its four chambers. If this process doesn't happen correctly, the heart can end up with only one working pumping chamber, as seen in DILV. Genetic changes, whether inherited or happening spontaneously, may play a role in disrupting this process. Often, there is no clear reason why the condition occurs. There is no one specific cause of DILV.

Children with DILV often have other heart differences. These include:

• Ventricular septal defect (VSD) – a hole between heart chambers
• Pulmonary stenosis or atresia – a narrowing (stenosis) or lack of development (atresia) of the pulmonary valve, which sends blood to the lungs
• Coarctation of the aorta – narrowing of the aorta after it leaves the heart, which can obstruct (block) appropriate blood flow to the body
• Transposition of the great arteries (TGA) – when the pulmonary artery and the aorta are switched compared to where they normally connect to the heart

These conditions can affect how blood flows through the heart.

What Are the Signs and Symptoms of Double Inlet Left Ventricle?

Symptoms of double inlet left ventricle in children can be different from child to child. Many babies show signs soon after birth.

Common symptoms include:

• Bluish skin, lips or fingernails (cyanosis)
• Fast breathing or trouble breathing
• Sweating
• Tiring easily during feeding
• Poor weight gain
• Swelling of the legs or belly (edema)
• Heart murmur (whooshing sound of the heartbeat) heard during an exam

Older children may also get tired more quickly during physical activity. If a baby or child shows signs of a heart problem, doctors will do tests to learn more.

How Doctors Diagnose Double Inlet Left Ventricle

Doctors use several tests to diagnose DILV. They listen to the heart, which may reveal a heart murmur. They check the baby’s oxygen levels.

Other tests may include:

• Echocardiogram – a heart ultrasound that shows blood flow
• Electrocardiogram (EKG) – a test that measures the heart’s electrical activity
• Chest X-ray – an image of the heart and lungs
• Cardiac CT or MRI – detailed images of the heart and blood vessels
• Cardiac catheterization – a procedure that measures pressure and blood flow in the heart

Often, DILV is diagnosed before birth during pregnancy. If a routine ultrasound shows abnormalities, the doctor may do a test called fetal echocardiography. It is a type of ultrasound that shows the baby’s heart while still in the womb.

What Are the Treatment Options for Double Inlet Left Ventricle?

Treatment focuses on helping blood move through the body more effectively. Newborns usually first need medicines or oxygen soon after birth and need very close monitoring in the intensive care unit. Babies generally need to stay in the hospital to have surgery before they are ready to go home.

Most children with DILV also need a series of surgeries.

Staged Heart Surgeries

Children with DILV usually have three surgeries over time. This is also called “single ventricle palliation”:

• Stage 1: Norwood procedure – Done in the first week of life. Surgeons create a new pathway for blood to reach the body and place a small tube (shunt) to send blood to the lungs.
• Interstage: This is the period between the first and second surgeries. Because babies have a shunt placed to get blood flow to their lungs, they are monitored very closely during this time. This may require staying in the hospital until the next surgery. But most babies are able to go home between surgeries.
• Stage 2: Glenn procedure – Done at about 3 to 6 months of age. Surgeons connect a large vein from the upper body directly to the lungs. This reduces the workload on the heart.
• Stage 3: Fontan procedure – Done between 18 and 36 months of age. Surgeons connect the vein from the lower body to the lungs. This helps separate oxygen-poor and oxygen-rich blood.

These are open-heart surgeries. This means the chest is opened and a heart-lung machine is used to do the work of these organs during the procedure. Together, these surgeries create a new pathway for blood flow. This allows the body to get more oxygen.

Other Treatments

Some children may also need catheter-based procedures. Doctors place a thin tube (catheter) into a blood vessel and guide it to the heart. This allows them to treat certain problems without opening the chest. This may involve using balloons or stents to open small or narrowed blood vessels and allow better flow of blood through the heart.

Recovery and Follow-Up Care

Recovery after heart surgery takes time. After the Norwood procedure, children stay in the hospital for three or four weeks. The later surgeries require one or two weeks in the hospital. Doctors monitor the child’s heart function, oxygen levels and feeding before they can go home.

Follow-up care may include:

• Regular visits with a heart specialist
• Imaging tests to check heart structure and blood flow
• Medicines to support heart function, such as diuretics, ACE inhibitors and blood thinners
• Guidance about activity and recovery

Because DILV is a lifelong condition, children will need ongoing heart care as they grow.

Long-Term Outlook for Children With Double Inlet Left Ventricle

Advances in heart surgery have improved outcomes for children with DILV. Children with DILV can often attend school, play and take part in many daily activities. But they will need lifelong monitoring by heart specialists.

After staged surgeries, many children develop a type of circulation called Fontan circulation. This allows blood from the body to flow directly to the lungs without passing through a pumping chamber.

Some people may develop complications later in life, so regular checkups are important. Complications can include irregular heartbeat, low oxygen levels, blood clots, liver congestion and heart failure.

As children grow older, care often transitions to doctors who specialize in adult congenital heart disease.

Living With Double Inlet Left Ventricle

Families play an important role in supporting their child’s heart health.

Helpful steps include:

• Encouraging safe physical activity recommended by the care team
• Keeping regular medical appointments
• Monitoring growth and development
• Providing emotional support and reassurance

Support groups and congenital heart disease resources can also help families connect with others facing similar challenges.

Frequently Asked Questions About Double Inlet Left Ventricle

Is double inlet left ventricle life-threatening?

DILV is a serious heart condition. With modern treatments and surgery, many children live longer and healthier lives than in the past.

Will my child need multiple surgeries?

Most children with DILV need a series of surgeries during childhood. These procedures help improve blood flow and oxygen levels.

Can DILV be detected before birth?

Yes. Many cases are found during pregnancy with a fetal echocardiogram, which shows the baby’s heart before birth.

Can children with DILV play sports?

Some children can participate in certain activities. A heart specialist will recommend safe levels of exercise based on the child’s condition.

How often will my child need heart checkups?

Children with DILV need lifelong follow-up with heart specialists. Regular visits help monitor heart function and catch any problems early.