What is double outlet right ventricle?

Double outlet right ventricle (DORV) is a congenital heart defect. There is a malformation of the fetal heart in the uterus leading to the right ventricle that has the two major arteries, namely the aorta and pulmonary artery arising from it.

How are hearts with DORV different?

Normal hearts have four chambers: two atria on top and two ventricles on the bottom. Two major blood vessels, or “great” arteries, normally connect to the ventricles.

• The aorta leaves the left ventricle and carries blood to the rest of the body.
• The pulmonary artery leaves the right ventricle and takes blood to the lungs. The blood picks up oxygen for the body.

With DORV, both great arteries connect to the right ventricle — either totally or in part. The left ventricle has just a part of either of the great arteries, or no artery at all.

Depending on the connections to the right ventricle, the body could receive oxygen-desaturated blood or the lung could receive excessive blood flow. The heart has to work harder to make up for the shortfall. DORV can also cause too much blood to get pumped into the lungs. This extra flow can damage both the heart and the lungs.

How common is DORV?

DORV is rare. It happens just once for every 6,000 to 10,000 newborns.

Are there different kinds of DORV?

Babies with DORV always have a ventricular septal defect (VSD), too. VSD is a hole in the septum, the wall between the two ventricles. Blood flows through the hole and between the ventricles. The other possible associated anomaly is pulmonary valve stenosis.

Healthcare providers classify DORV by the location of the hole:

• DORV with subaortic VSD: The VSD is just under the aorta.
• DORV with subpulmonary VSD (also called Taussig-Bing): The VSD is just under the pulmonary artery.
• DORV with doubly committed VSD: There is a VSD under each of the great arteries.
• DORV with non-committed (or remote) VSD: The VSD is not near the aorta or the pulmonary artery.

What causes DORV?

Scientists don’t completely understand what causes DORV. In some cases, it happens to babies who have problems with their chromosomes, the cell structures that hold their DNA.

What are the symptoms of DORV?

Symptoms of DORV usually appear during the first days or weeks after birth. They’re like symptoms of other congenital heart problems and include:

• Cyanosis (blue-ish or purple-ish skin, lips or nails).
• Difficulty breathing, such as tachypnea (really fast breathing) or shortness of breath.
• Difficulty eating or gaining weight.
• Heart murmur (extra sound in the heartbeat, which a healthcare provider can hear with a stethoscope).
• Sweating a lot, such as while eating.
• Tachycardia (heart rate faster than 100 beats a minute).
• Unusual sleepiness or seeming “out of it.”

What other problems can a baby with DORV have?

Babies with DORV often have other congenital problems:

• Ciliary dysfunction: Problems develop with tiny hair-like structures that line the airway.
• Heterotaxy: Organs in the chest and belly are not in the usual places.
• Intestinal malrotation: With intestinal malrotation, a baby’s intestines twist in a way that isn’t normal.
• Pulmonary stenosis: With pulmonary stenosis, the pulmonary valve (between the right ventricle and pulmonary artery) is too small or stiff.
• Ventricular hypoplasia: One or both ventricles are smaller than normal.

When is DORV diagnosed?

Sometimes healthcare providers can find a heart defect before a baby is born. They may do so during a routine ultrasound screening called a fetal echocardiogram.

If not, DORV is usually diagnosed in the days or weeks after birth because the baby has symptoms.

What tests will the baby need to confirm DORV?

Sometimes a healthcare provider spots DORV before a baby is born. In other cases, the first signs of a heart problem get noticed with birth. Either way, the baby needs an exam:

• The healthcare provider will look for signs of cyanosis.
• Using a stethoscope, the healthcare provider will listen to the heart.
• The provider will use pulse oximetry (pulse ox) screening to measure the amount of oxygen in the blood. The test is simple and pain-free.

Then the healthcare provider may order one or more tests:

• Initial imaging tests: CT, MRI and X-ray are common ways to take pictures inside the body.
• Electrocardiogram (ECG or EKG): An electrocardiogram is a painless test that measures electrical activity in the heart.
• Echocardiogram (echo): An echocardiogram is also pain-free and measures sound waves from the chest to create images of the heart.
• Cardiac catheterization (cardiac cath): Cardiac catheterization is also called an angiogram. A thin tube goes through a vein and into the heart to get details on heart function.

How is DORV treated?

Almost all babies with DORV need open-heart surgery within the first year of life. Your healthcare provider will help you make decisions about surgery by considering:

• Other problems with the baby’s heart or other organs.
• Overall health.
• Type of DORV.

The surgeon may take one of the following approaches:

• Biventricular repair (also called arterial switch): If both ventricles are in good shape and DORV is not complex, the surgeon may recommend biventricular repair. This approach moves the aorta to the left ventricle.
• Intraventricular repair: The surgeon creates a tunnel through the VSD to connect the aorta to the left ventricle. The tunnel is called a baffle.
• Univentricular repair (Fontan operation): For more complex cases of DORV, the surgeon may recommend this procedure. It redirects blood flow from the lower body to the lungs.

Can I prevent DORV?

There is no way to prevent DORV. Scientists are still trying to understand its cause.

What is the outlook for a baby with DORV?

Without surgery, a baby with DORV will eventually develop:

• Cyanosis.
• Heart failure.
• Pulmonary hypertension (high blood pressure in the lungs).

With biventricular repair, people often live a normal life, with at least an average lifespan. People who needed other procedures may have shorter lifespans, and they may need further surgery later in life. Anyone who’s had surgery for DORV needs lifelong care from a cardiologist.

What are the risks of surgery?

Most babies have good outcomes from surgery for DORV. But any heart surgery has risks, such as:

• Bleeding.
• Blood clots, which can cause a stroke or heart attack.
• Infection.
• Problems coming out of anesthesia.
• Respiratory failure.
• Unusual heart rhythms and heart block, needing a pacemaker.

What should I ask my baby’s healthcare provider?

• What kind of DORV does my child have?
• What kind of surgery is needed?
• When should my baby have the surgery?
• What are the risks of having surgery?
• What are the risks of not having surgery?
• Will my baby need to see a specialist?
• Will the surgery fix the defect, or will my child need more surgeries?
• Will my baby need to take medications?

A note from Cleveland Clinic

Double outlet right ventricle is a serious condition that happens when the heart doesn’t develop correctly in the womb. While it can lead to serious heart and lung problems, timely treatment can keep your baby safe. Surgery and regular checkups can help people born with DORV live healthier, longer lives.