What is double inlet left ventricle?

The human heart has four chambers. The top chambers, the right and left atria, receive blood that flows into the heart. The bottom chambers, the right and left ventricles, pump blood out of the heart. In a healthy heart, the right atrium receives blood that has traveled through the body and has little oxygen left in it. The right ventricle pumps blood out to the lungs through a large blood vessel called the pulmonary artery. The blood picks up oxygen in the lungs, travels back to the left side of the heart and is pumped out to the body through a large blood vessel called the aorta. Because the pulmonary artery and the aorta are the largest blood vessels in the body, doctors sometimes call them the great vessels or the great arteries.

Double inlet left ventricle (DILV) is a form of congenital heart disease where only one pumping chamber (the left ventricle) develops normally. The right ventricle is very small. Both valves that provide blood from the atria to the pumping chambers empty into the left ventricle; this is why the condition is called double inlet left ventricle. DILV is a form of single ventricle heart disease.

In a healthy heart, the pulmonary artery (the blood vessel that pumps blood from the heart to the lungs) is attached to the right ventricle, and the aorta (the blood vessel that pumps oxygen-rich blood to the body) is attached to the left ventricle. In DILV, the pulmonary artery is usually connected to the left ventricle, and the aorta is connected to the small right ventricle. When this occurs, it is called transposition of the great arteries. 

In rare cases, the great arteries are attached normally, even though both valves empty into the left ventricle. This is called a “Holmes heart.” 

Signs and symptoms of double inlet left ventricle

In many cases, children with double inlet left ventricle will be diagnosed before they are born.

If DILV is not diagnosed before birth, a baby may be born in critical condition, as the aorta is too small to adequately provide blood to the body.  Symptoms may include some or all of the following: 

• Tiredness or listlessness
• Poor feeding
• Paleness or a gray color to the skin
• Fast breathing

Children with a Holmes heart may only have a few or no symptoms; however, a heart murmur (an abnormal heart sound when a doctor listens with a stethoscope) may be heard, which is caused by narrowing of the pulmonary artery. If the narrowing is severe, the baby’s skin may appear to have a blueish tint.

Testing and diagnosis for double inlet left ventricle

In many cases, double inlet left ventricle is diagnosed before a baby is born. The Fetal Heart Program at Children’s Hospital of Philadelphia (CHOP) leads the nation in the evaluation, diagnosis and treatment of fetal heart disease before birth. Our experts will monitor both you and your baby throughout your pregnancy and create a plan for labor and care for your newborn after birth.

CHOP is also home to the Richard D. Wood Jr. Center for Fetal Diagnosis and Treatment’s Garbose Family Special Delivery Unit (SDU), the world’s first birthing facility for healthy mothers carrying babies with known birth defects. The SDU is very close to the cardiac operating rooms and cardiac patient care rooms. Babies born in the SDU are in the care of pediatric cardiologists and specially trained cardiac nurses immediately after birth. Your doctor will discuss the possibility of delivering in the SDU with you.

After a baby is born, diagnosing double inlet left ventricle may require some or all of these tests: 

• Electrocardiogram (EKG or ECG), which is a record of the electrical activity of the heart
• Echocardiogram (also called echo or ultrasound), which is when sound waves create an image of the heart
• Chest X-ray
• Cardiac MRI, or CT scan, which is a 3D image that shows the heart's structures in detail

Sometimes, cardiac catheterization will be required. A thin, flexible tube (catheter) is inserted through a vein or artery in the leg and into the heart to provide detailed information about the structure and function of the heart and lungs.

Treatment for double inlet left ventricle

Double inlet left ventricle is usually fatal without early intervention. However, due to enormous strides in medicine and technology, there are now many different options for treating DILV. Our team of Cardiac Center experts take an individualized approach for each child. Your doctor will explain each option to you in detail and explain why one approach may be the best for your child.

DILV surgery

Typically, your child will require open-heart surgery to re-direct the oxygen-rich and oxygen-poor blood. This series of three reconstructive surgeries is known as staged reconstruction. 

After staged reconstruction, the left ventricle will pump oxygenated blood to the body, and the deoxygenated (oxygen-poor) blood will flow from the veins to the lungs without passing through the heart. This is called Fontan circulation. 

In DILV, the first operation usually occurs within the first few days of life. The type of surgery depends on your child’s individual anatomy. 

If your child has transposition of the great arteries, they will undergo a procedure similar to the Norwood procedure.

If your child has a Holme’s heart – or not enough blood flows to the lungs but enough blood is able to flow to the body – your doctor may perform a procedure to allow more blood to flow through the lungs. This may be a tube (called a BTT shunt) or a small stent placed in the patent ductus arteriosus (the natural connection between the aorta and the pulmonary artery). In some rare cases, there is enough blood flow to the lungs and no first procedure is needed. 

The second and third procedures (the Glenn and the Fontan surgeries) are similar to those performed for children with single ventricle defects. The Glenn procedure usually occurs when your baby is 3-7 months old, and the Fontan is performed between 2-3 years. Your child will need regular follow-ups and testing to monitor their health and reduce risk factors before the Fontan. Sometimes, additional procedures or even a heart transplant (in rare cases) may be needed. Your child’s doctor will work closely with you to provide the best care for your child.

Follow-up care 

Between surgeries

Though early outcomes for children with single ventricle heart defects after staged reconstruction have greatly improved over the years, the time between the Norwood procedure and the Glenn operation is a very vulnerable time for infants. Our Infant Single Ventricle Monitoring and Management Program provides care and monitoring for babies with single ventricle heart defects between two necessary heart repair procedures.

Children who have had surgical reconstruction for DILV require ongoing care by a pediatric cardiologist experienced in congenital heart disease. Sometimes children with DILV experience serious health problems. Many remain on medication, and additional surgeries may be required.

Children with complex congenital heart defects who have had open heart surgery as infants are at a higher risk for neurodevelopmental issues when compared to children without congenital heart defects. CHOP’s Cardiac Kids Developmental Follow-up Program provides evaluation, screening and clinical care for children with complex congenital heart disease who are at risk for neurodevelopmental problems.

As patients with Fontan circulation get older, doctors are recognizing that, while some do fine, many experience complications. These complications can include lung, liver and gastrointestinal diseases. Our Single Ventricle Survivorship Clinic, part of the Fontan Rehabilitation, Wellness, Activity and Resilience Development (FORWARD) Program specializes in the care of these patients and is researching improved treatments for them.

Into Adulthood

Our pediatric cardiologists follow patients until they are young adults. The Philadelphia Adult Congenital Heart Center, a joint program of CHOP and Penn Medicine, meets the unique needs of adults who were born with heart defects. At CHOP’s Cardiac Center, we support our adolescent and young adult patients through a smooth and seamless transition to adult cardiology care at the Philadelphia Adult Congenital Heart Center or, if desired, to a cardiologist with congenital heart disease expertise in another location.