Double Outlet Right Ventricle (DORV) is a congenital heart defect, meaning it is present at birth. If this defect is detected, this means blood with very little oxygen goes to the body, or too much blood goes into the lungs.
Physiologically, the large artery that brings oxygen-rich blood to the body (the aorta) and the large artery that delivers oxygen-depleted blood to the lungs (the pulmonary artery) connect to the same heart chamber (ventricle). The right side of the heart pumps blood to the lungs and the body.
Another congenital heart defect, a ventricular septal defect (VSD), almost always occurs with DORV.
VSD is a hole between the lower chambers of the heart, the ventricles, and oxygenated and deoxygenated blood mixes before being pumped out to the lungs or the body.
One in every 6,000 to 10,000 babies is born with a double outlet right ventricle.
Healthy heart structure and function
In a normal, healthy heart, the aorta (the large main artery) connects to the left ventricle and brings oxygenated blood to the body in this pattern:
- The right side of the heart pumps blood into the lungs via the large pulmonary arteries, where it picks up oxygen.
- This oxygen-rich blood enters the left side of the heart and circulates into the rest of the body via a large artery called the aorta.
- The oxygen-depleted blood from the body enters the right side of the heart.
- The circuit begins again.
The left ventricle is the heart chamber that pumps blood to the body, and the right ventricle is the heart chamber that pumps blood to the lungs. The oxygenated and deoxygenated blood never mix.
In a person with a double outlet right ventricle, the pulmonary artery and over half of the aorta comes off the right ventricle instead of the left. As a result, deoxygenated blood goes back to the body instead of the lungs to get more oxygen, or too much blood goes to the lungs.
DORV may also be associated with other congenital heart defects, such as heart valve defects.
DORV is always associated with a ventricular septal defect, which is crucial to keep the child alive until surgery can be done to repair the defects. Without the VSD, blood would only be able to reach the lungs, and no blood would go to the body. The VSD, which is a hole between the two ventricles, allows oxygenated and deoxygenated blood to mix. As a result, blood that reaches the body has less oxygen than usual.
The type of DORV depends on the location of the ventricular septal defect in relation to the great arteries. The severity of the heart defect and the symptoms is determined by the type of DORV.
An infant with a double outlet right ventricle may have these symptoms:
- Difficulty breathing.
- Swollen legs or abdomen.
- Tiring while feeding.
- Poor weight gain and growth.
- Bluish hue to the lips, nail beds, or skin (cyanosis).
- Clubbing (thickening) of toes and fingers is a late symptom.
Other medical conditions often associated with DORV include:
- Ciliary dysfunction (trouble with the little hairs that line the airways).
- Heterotaxy (abnormal placement of internal organs).
- Intestinal malrotation (intestines twist in strange directions).
- Pulmonary stenosis (a small or stiff valve between the right ventricle and the pulmonary artery).
- Ventricular hypoplasia (one or both ventricles are smaller than usual).
If not treated quickly, DORV can cause complications such as high blood pressure in the lungs, permanent lung damage, and death.
Lung, liver, or gastrointestinal tract problems can also occur, as well as possible neurodevelopmental issues.
A doctor may diagnose a double outlet right ventricle with a fetal echocardiogram, which is an ultrasound performed on a fetus before birth.
After birth, the pediatrician may notice:
- An enlarged heart.
- A heart murmur.
- Rapid breathing.
- Rapid heart rate.
If they notice these symptoms, the pediatrician will order extra tests to diagnose the defect.
The presence of other congenital heart defects can complicate a DORV and may make it difficult to diagnose. This can include defects in the heart muscle and valves as well as a ventricular septal defect. DORV can also mimic other congenital heart defects, such as:
- Tetralogy of Fallot.
- Functional single ventricle.
- Transposition of the great arteries.
Medical scans and other diagnostic imaging will be necessary to assess the situation and determine treatment. These include:
- Cardiac catheterization.
- Chest x-ray.
- CT scan.
Open heart surgery within days or months of birth is usually necessary. A surgeon will close the VSD, redirect blood into the aorta, or move one or both arteries to the proper places as needed. More than one surgery may be necessary.
The type of surgery depends on the type of DORV, the number of defects present, the severity of defects, and the general health of the infant.
If the lungs have enough blood flow, your doctor may also decide to place a temporary shunt between the aorta and the pulmonary artery, which the surgeon will remove during later open-heart surgery.
Complications that could occur after open-heart surgery include:
- Blood clots.
- Respiratory failure.
- Anesthesia-related problems.
The outlook for the infant after surgery depends on:
- The size and location of the VSD.
- The location of the arteries.
- The presence of other heart or artery defects.
- The general health of the infant.
- Associated lung damage.
After surgery, children will need life-long care and follow-up exams to monitor their heart and artery function but can generally live active and productive lives far into adulthood.
Some people may need medication to improve heart function and make it easier for the heart to pump.
Additional procedures or surgeries for heart valve repair or replacement may also be necessary for some situations.
The double outlet right ventricle is a heart defect present at birth.
At least part of both large arteries connects to the right ventricle. The single ventricle pumps oxygen-rich and oxygen-depleted blood to the body, and too much blood may enter the lungs. This condition is always associated with a ventricular septal defect and may be associated with other congenital heart defects, such as valve malformations.
Treatment depends on the specific anatomical abnormalities in the heart and great vessels. Surgery to repair the defect is usually necessary within days to months of birth, but these infants can generally live active and productive lives.
Cleveland Clinic. (2022). Double Outlet Right Ventricle: Repair, Symptoms & Types (clevelandclinic.org)
Mayo Clinic. (2022). Double-outlet right ventricle - Overview - Mayo Clinic
Children’s Hospital of Philadelphia. Double Outlet Right Ventricle | Children's Hospital of Philadelphia (chop.edu)
MedlinePlus. (2020). Double outlet right ventricle : MedlinePlus Medical Encyclopedia