Heterotaxy Syndrome

What is heterotaxy syndrome?

Heterotaxy syndrome, also known as heterotaxia or atrial isomerism, occurs when your internal organs are in a different location from what’s expected in your chest and abdomen. The expectation for all humans is that, when you’re born, your organs are in a specific location in your body. For example, if you’re born with heterotaxy, your heart and spleen could be on the right side of your body instead of your left. This could cause serious health complications that can be life-threatening.

The word heterotaxy is Greek and combines the words “heteros” which means different and “taxis” which means arrangement.

What organs does heterotaxy syndrome affect in my body?

Heterotaxy syndrome can affect the position and function of your:

• Heart.
• Lungs.
• Liver.
• Spleen.
• Intestines.

How does heterotaxy syndrome relate to situs solitus and situs inversus?

Heterotaxy syndrome occurs when your internal organs aren’t in a location that’s expected between your chest and abdomen. This condition can cause serious health problems. Heterotaxy syndrome is a diagnosis that’s different from situs solitus or situs inversus.

Situs solitus is the expected position of your internal organs. If you have heterotaxy syndrome, the organs in your chest and abdomen aren’t in their expected position.

Situs inversus occurs when your internal organs mirror their expected position. For example, you’re born with your heart on the right side of your chest instead of your left side. Situs inversus rarely causes health problems like heterotaxy syndrome.

Who does heterotaxy syndrome affect?

Heterotaxy syndrome can affect anyone since the condition is the result of genetic changes. The majority of people diagnosed with heterotaxy syndrome received a mutated gene sporadically, or randomly. You’re more at risk of having a child with heterotaxy syndrome if you have a history of congenital heart conditions in your biological family.

How common is heterotaxy syndrome?

Heterotaxy syndrome affects an estimated 1 in 10,000 newborns worldwide. Some studies suggest that this estimate could be more common since the condition can be underdiagnosed.

The condition accounts for about 3% of all heart conditions present at birth (congenital heart conditions).

What are the symptoms of heterotaxy syndrome?

The main symptom of heterotaxy syndrome is when the internal organs in your chest and abdomen aren’t arranged in their expected location in your body. Your organs could be missing or they didn’t form correctly during fetal development. This causes symptoms that could include:

• Internal organs not working correctly (heart, lungs, liver, spleen, intestines).
• Abnormal structure of your heart (congenital heart condition).
• Twisted intestines (malrotation).
• Missing spleen (asplenia) or divided spleen (polysplenia).

Symptoms caused by your internal organs not working as they should include:

• Breathing difficulties.
• Inability to fight infections.
• Blue or pale color to your skin (cyanosis).
• Stomach or abdominal pain.
• Difficulty eating, gaining weight or digesting food.
• Irregular heartbeat.
• Fluid or mucous buildup in your lungs.

What causes heterotaxy syndrome?

There are several possible causes of heterotaxy syndrome.

A genetic mutation of one of over 60 genes can cause heterotaxy syndrome. There are different ways that you can inherit the condition by receiving:

• One copy of the mutated gene from one of your parents during conception (autosomal dominant).
• One copy of the mutated gene from both of your parents during conception (autosomal recessive).
• A new copy of a mutated gene that doesn’t have a pattern of inheritance in your family history (sporadic or de novo).
• A genetic mutation exists on your X chromosome (X-linked), which is your sex chromosome. This is most common among men and people assigned male at birth (AMAB) since they have only one X chromosome.

In addition to genetic factors, environmental factors — like exposure to a chemical or toxin during pregnancy — could cause heterotaxy syndrome in a developing fetus.

Studies are ongoing to learn more about the causes of heterotaxy syndrome, including cases where neither a genetic mutation nor environmental factors play a role in the development of symptoms.

How is heterotaxy syndrome diagnosed?

Your healthcare provider will diagnose heterotaxy syndrome after a physical exam and imaging tests that include one of the following:

• An MRI.
• A CT scan.
• An echocardiogram.

If your provider suspects heterotaxy syndrome after imaging tests, they’ll offer blood tests or additional tests to check the function of your internal organs, which include:

• A blood test to check the health of your spleen.
• An endoscopy.
• A kidney function test.
• A renal ultrasound.

When does a heterotaxy syndrome diagnosis occur?

Heterotaxy can be diagnosed before birth by prenatal ultrasound or echocardiography. Most people receive a heterotaxy syndrome diagnosis shortly after birth. Usually, symptoms of a congenital heart condition lead to a heterotaxy diagnosis. Some people who don’t have severe symptoms might receive a diagnosis later during childhood. More rare cases occur during adulthood after receiving an imaging test for another medical concern, which can lead to an incidental heterotaxy syndrome diagnosis.

How is heterotaxy syndrome treated?

Treatment for heterotaxy syndrome is unique to each person based on the affected organs in your body. The most common treatment is surgery to adjust or correct any growth or function abnormalities in your chest and abdomen. Multiple surgeries might be necessary to treat this condition throughout your life and can begin during early infancy. Types of surgery could include:

• Heart surgery to improve the function of your heart or adjust any congenital heart abnormalities.
• Fontan procedure: Heart surgery to create one ventricle that pumps blood to your lungs and your body.
• Ladd procedure: Surgery to untwist and remove intestine blockages.
• Heart transplant: Surgery to replace your heart with a donor’s heart. This procedure might be necessary for adults who had several heart surgeries in their lifetime.

Additional treatment options could include:

• Inserting a pacemaker to control your heart’s rhythm.
• Taking medicine to lower blood pressure.
• Taking antibiotics to help your spleen fight infections (prophylactic antibiotics).

How soon after treatment will I feel better?

Your recovery time after treatment varies based on the type of surgery. You’ll need plenty of rest after surgery to let your body heal. Most heart surgeries require several days to a few weeks of around-the-clock monitoring in the hospital to make sure the procedure was effective and that there are no side effects. Some treatment options can take several months until your body is fully healed. Before your surgery, your provider will outline the steps you’ll need to take to keep your body safe after surgery and improve your healing time.

How can I prevent heterotaxy syndrome?

Since some causes of heterotaxy syndrome are the result of genetic changes, you can’t prevent the condition. To learn more about your risks during pregnancy, talk to your healthcare provider about genetic testing.

If you’re pregnant, you can make sure the developing fetus is healthy by avoiding chemical exposure or exposure to toxins, like pesticides and lead-based products, which could cause the condition.

What is the life expectancy for a person diagnosed with heterotaxy syndrome?

Your prognosis for heterotaxy syndrome is dependent on the severity of your diagnosis. Severe forms of the condition can be life-threatening for infants and children, even with treatment. Mild cases of the condition lead to a normal life expectancy with minor health problems that improve with treatment and frequent monitoring. Contact your healthcare provider if you notice irregularities in your heartbeat or you have chest or abdominal pain.

When should I see my healthcare provider?

Visit your healthcare provider if:

• Your skin turns blue or a pale gray color.
• You can’t eat or drink.
• You have a wound that won’t heal or a wound that swells, leaks yellow pus or has a crusty exterior.

When should I go to ER?

Visit the emergency room or call 911 if you have:

• Severe chest pain or abdominal pain.
• An irregular heartbeat.
• Difficulty breathing.

What questions should I ask my doctor?

• How severe is my diagnosis?
• Do I need surgery or multiple surgeries?
• How do I prepare for surgery?
• What is my recovery time after surgery?
• Are there side effects to the treatment you recommend?

What does isomerism mean?

Isomerism is a term used in chemistry that relates to multiple compounds that have the same chemical formula but different structures. Heterotaxy syndrome is also known as isomerism because your internal organs are able to function as they should but they aren’t in their expected location in your body.

What is the ICD for heterotaxy syndrome?

The International Classification of Diseases (ICD) is a diagnostic tool for healthcare providers to classify conditions in clinical settings. The ICD-10-CM code for heterotaxy syndrome is Q89.3.

A note from Cleveland Clinic

If you’re a parent and your newborn received a heterotaxy diagnosis, you could be feeling a range of emotions. Your providers will work closely with specialists to make sure your baby is healthy and that their symptoms aren’t life-threatening. Ongoing treatment is necessary to make sure complications and symptoms of the condition don’t interfere with your child’s ability to thrive and live a full life. If you’re planning on becoming pregnant and want to better understand your risk of having a child with a genetic condition like heterotaxy syndrome, talk to your provider about genetic testing or genetic counseling.