Cor Triatriatum: Causes, Symptoms, and Treatment
Medically reviewed by Achuta Uppu, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Cor Triatriatum?
A cardiologist, a heart doctor, usually cares for cor triatriatum. Children often see a pediatric cardiologist, a heart doctor for children. A cardiac surgeon, a heart surgeon, does the repair. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is cor triatriatum?
Cor triatriatum is an extremely rare heart defect that is present at birth. A thin membrane, a thin sheet of tissue, divides one of the upper heart chambers, called an atrium, into two parts.
In the most common type, called cor triatriatum sinister, the left atrium is divided. In the other type, called cor triatriatum dexter, the right atrium is divided.
Symptoms, how severe they are and when they start vary.
Symptoms
Signs often appear early in life. They may include:
- Fast breathing.
- Wheezing and coughing.
- Fluid in the lungs.
- A heart murmur, an unusual heart sound, often found in newborns.
- Poor growth and weight gain, and trouble feeding, in children.
Some people are not diagnosed until adulthood. Other common features include:
- Shortness of breath during activity, at rest, or when lying flat.
- Feeling tired easily.
- A racing or fluttering heartbeat, called palpitations.
Atrial fibrillation, an irregular heartbeat, can cause blood clots that lead to a stroke or a clot in the lungs.
Causes and who gets it
Cor triatriatum comes from abnormal development of the heart before birth. In the left-sided type, it likely happens because the veins from the lungs are not fully taken into the heart during early development.
No known genetic changes or risk factors have been linked to it.
It affects males and females equally. In the United States, it accounts for only 0.1% to 0.4% of babies born with congenital heart disease.
It often occurs along with other heart defects, such as a hole between the upper heart chambers or between the lower heart chambers.
How doctors diagnose it
A doctor may hear a heart murmur during a routine checkup. Imaging tests, which are pictures of the heart, are used to diagnose it.
A chest x-ray is often the first test. An echocardiogram, an ultrasound picture of the heart, is the main test. It shows exactly where the membrane is.
An electrocardiogram (ECG), which records the heart's electrical activity, may show an irregular heartbeat. Its results are not specific to this condition.
If the picture is unclear, doctors may do a transesophageal echocardiogram, an ultrasound done from inside the food pipe.
Heart catheterization, where a thin tube is guided into the heart, can show how much the membrane blocks blood flow. CT and MRI scans are mostly used for harder cases.
Treatment
Treatment depends on symptoms. People with no symptoms need no specific treatment but should have regular checkups.
People with symptoms need surgery. Surgery is the main treatment. The surgeon removes the abnormal membrane in the atrium.
Before surgery, doctors may treat extra fluid in the lungs and control an irregular heartbeat.
The surgeon reaches the heart through the breastbone, and a heart-lung machine takes over during the operation. Surgery should be done at a center with experience in this condition.
About 83% of people are alive 10 years after surgery. People with other heart defects may face higher risks.
Cor triatriatum is rare but treatable. Respiratory infections should be treated early, because people with this condition are prone to infection of the lining of the heart.
When to see a doctor
See a doctor if you or your child has fast breathing, wheezing, poor weight gain, or a heart murmur. People with no symptoms still need regular checkups.
Call 911 or go to the emergency room for severe trouble breathing, chest pain, fainting, or sudden weakness or trouble speaking.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. A direct primary care doctor can listen for heart murmurs, arrange heart imaging, and keep track of visits with a heart specialist.
Common questions
Is cor triatriatum treatable?
Yes, it is treatable with surgery. People with symptoms need surgery to remove the membrane.
Is cor triatriatum a birth defect?
Yes, it is a heart defect that is present at birth.
Can cor triatriatum first be found in adults?
Yes, but it is rare. In adults, symptoms may not appear until the membrane thickens or hardens, which narrows the opening.
Does cor triatriatum run in families?
Not as far as doctors know, because no gene change or risk factor has been linked to it.
Does everyone with cor triatriatum need surgery?
No, people with no symptoms need no specific treatment but should have regular checkups.
Sources
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
