Double inlet left ventricleDefinition:
Double inlet left ventricle (DILV) is a heart defect that is present from birth (congenital). It affects the valves and chambers of the heart. Babies born with this condition have only one working pumping chamber (ventricle) in their heart.
DILV; Single ventricle; Common ventricle
DILV is one of several heart defects known as single (or common) ventricle defects. People with this condition generally have a large left ventricle (the pumping chamber of the heart that supplies the body with blood), and a small right ventricle (the pumping chamber that supplies the lungs with blood).
In the normal heart, the right and left lower chambers (ventricles) receive blood from the right and left upper chambers (atria). Oxygen-poor blood returning from the body flows to the right atrium and right ventricle. The right ventricle then pumps blood to the pulmonary artery. This is the blood vessel that carries blood to the lungs to pick up oxygen.
The blood with fresh oxygen returns to the left atrium and left ventricle. The aorta then carries oxygen-rich blood to the rest of the body from the left ventricle.
However, in people with DILV, only the left lower heart chamber is developed, and both upper chambers carry blood into this ventricle. This means that oxygen-rich blood mixes with oxygen-poor blood. The mixture is then pumped into both the body and the lungs.
DILV can happen if the large blood vessels leading to the heart are in the wrong positions. (The aorta leads from the small right ventricle and the pulmonary artery leads from the left ventricle.) It can also occur when the arteries are in the normal position and lead from the usual ventricles. In this case, blood flows from the left to right ventricle through a hole between the chambers called a ventricular septal defect (VSD).
Double inlet left ventricle is very rare. The exact cause is unknown. The problem most likely occurs early in the pregnancy, when the baby's heart develops. People with DILV often also have other heart problems, such as:
Symptoms of DILV may include:
- Becoming tired easily, especially during feeding
- Bluish color to the skin and lips (cyanosis) due to low oxygen in the blood
- Failure to gain weight and grow
- Pale skin (pallor)
- Poor feeding
- Swollen legs or abdomen
- Trouble breathing
Exams and Tests:
Signs of DILV may include:
- Abnormal heart rhythm, as seen on an electrocardiogram
- Buildup of fluid around the lungs
- Heart failure
- Heart murmur
- Rapid heartbeat
Tests to diagnose DILV may include:
- Chest x-ray
- Measurement of the electrical activity in the heart (electrocardiogram, or ECG)
- Passing a thin, flexible tube into the heart to examine the arteries (cardiac catheterization)
- Ultrasound exam of the heart (echocardiogram)
- Using magnets to create images of the heart (MRI)
Surgery is needed to improve blood circulation through the body and into the lungs. The most common surgeries to treat DILV are a series of two to three operations. These surgeries are similar to the ones used to treat hypoplastic left heart syndrome and tricuspid atresia .
The first surgery may be needed when the baby is only a few days old. In most cases, the baby can go home from the hospital afterward. The child will most often need to take medicines every day and be closely followed by a pediatric cardiologist. The child’s doctor will determine when the second stage of surgery should be done.
The next surgery (or first surgery, if the baby didn't need a procedure as a newborn) is called the bidirectional Glenn shunt or Hemifontan procedure. This surgery is usually done when the child is 4 - 6 months old.
After the child has had the above operations, he or she may still look blue (cyanotic). The final step is called the Fontan procedure. This surgery is most often done when the child is 18 months - 3 years old. After this final step, the baby is no longer cyanotic.
The Fontan operation does not create normal circulation in the body. However, it improves circulation enough for the child to live and grow.
A child may need more surgeries for other defects, or to extend survival while waiting for the Fontan procedure.
Your child may need to take medicines before and after surgery. These may include:
- Anticoagulants to prevent blood clotting
- ACE inhibitors to reduce blood pressure
- Digoxin to help the heart contract
For the most severe cases of DILV, a heart transplant may be recommended.
DILV is a very complex, hard-to-treat heart defect. How well the baby does depends on several factors, including:
- Baby's overall condition at the time of diagnosis and treatment
- Presence of other heart abnormalities
- Severity of the defect
Advances in surgical techniques allow many infants with DILV to reach adulthood. However, these children and adults require regular follow-ups. They also face many complications and may have to limit their physical activities.
Complications of DILV include:
- Clubbing (thickening of the nail beds) on the toes and fingers (late sign)
- Congestive heart failure
- Frequent pneumonia
- Heart rhythm problems
When to Contact a Medical Professional:
Call your health care provider if your child:
- Seems to tire easily
- Has trouble breathing
- Has bluish skin or lips
Also talk to your health care provider if your baby is not growing or gaining weight.
There is no known prevention.
Baldwin HS, Dees E. Embryology and physiology of the cardiovascular system. In: Gleason CA, Devaskar S, eds. Avery's Diseases of the Newborn. 9th ed. Philadelphia, PA: Saunders Elsevier; 2011:chap 50.