BACK
TO
TOP
Browse A-Z
Print-Friendly
Bookmarks
bookmarks-menu

Endocardial cushion defect

Atrioventricular (AV) canal defect; Atrioventricular septal defect; AVSD; Common AV orifice; Ostium primum atrial septal defects; Congenital heart defect - ECD; Birth defect - ECD; Cyanotic disease - ECD

Endocardial cushion defect (ECD) is an abnormal heart condition. The walls separating all four chambers of the heart are poorly formed or absent. Also, the valves separating the upper and lower chambers of the heart have defects during formation. ECD is a congenital heart disease, which means it is present from birth.

Causes

ECD occurs while a baby is still growing in the womb (uterus). The endocardial cushions are two thicker areas that develop into the walls (septum) that divide the four chambers of the heart. They also form the mitral and tricuspid valves. These are the valves that separate the atria (top collecting chambers) from the ventricles (bottom pumping chambers).

The lack of separation between the two sides of the heart causes several problems:

  • Increased blood flow to the lungs. This results in increased pressure in the lungs. In ECD, blood flows through the abnormal openings from the left to the right side of the heart, then to the lungs. More blood flow into the lungs makes the blood pressure in the lungs rise.
  • Heart failure. The extra effort needed to pump makes the heart work harder than normal. The heart muscle may enlarge and weaken. This can cause swelling in the baby, problems in breathing, and difficulty in feeding and growing.
  • Cyanosis. As the blood pressure increases in the lungs, blood starts to flow from the right side of the heart to the left. The oxygen-poor blood mixes with the oxygen-rich blood. As a result, blood with less oxygen than usual is pumped out to the body. This causes cyanosis, or bluish skin.

There are two types of ECD:

  • Complete ECD. This condition involves an atrial septal defect (ASD) and a ventricular septal defect (VSD). People with a complete ECD have only one large heart valve (common AV valve) instead of two distinct valves (mitral and tricuspid).
  • Partial (or incomplete) ECD. In this condition, only an ASD, or an ASD and VSD are present. There are two distinct valves, but one of them (the mitral valve) is often abnormal with an opening (cleft) in it. This defect can leak blood back through the valve.

ECD is strongly linked to Down syndrome. Several gene changes are also linked to ECD. However, the exact cause of ECD is unknown.

ECD may be associated with other congenital heart defects, such as:

Symptoms

Symptoms of ECD may include:

  • Tires easily
  • Bluish skin color, also known as cyanosis (the lips may also be blue)
  • Feeding difficulties
  • Failure to gain weight and grow
  • Frequent pneumonia or infections
  • Pale skin (pallor)
  • Rapid breathing
  • Rapid heartbeat
  • Sweating
  • Swollen legs or abdomen (rare in children)
  • Trouble breathing, especially during feeding

Exams and Tests

During an exam, your child's health care provider will likely find signs of ECD, including:

Children with partial ECD may not have signs or symptoms of the disorder during childhood.

Tests to diagnose ECD include:

  • Echocardiogram, which is an ultrasound that views the heart structures and blood flow inside the heart
  • ECG, which measures the electrical activity of the heart
  • Chest x-ray, which produces an image of the heart and large arteries
  • MRI, which provides a detailed image of the heart
  • Cardiac catheterization, a procedure in which a thin tube (catheter) is placed into the heart to see blood flow and take accurate measurements of blood pressure and oxygen levels

Treatment

Surgery is needed to close the holes between the heart chambers, and to create distinct tricuspid and mitral valves. The timing of the surgery depends on the child's condition and the severity of the ECD. It can often be done when the baby is 3 to 6 months old. Correcting an ECD may require more than one surgery.

Your child's provider or surgeon may prescribe medicine:

  • To treat the symptoms of heart failure
  • Before surgery if ECD has made your baby very sick

The medicines will help your child gain weight and strength before surgery. Medicines often used include:

  • Diuretics (water pills)
  • Medicines that make the heart contract more forcefully (inotropic agents)

Surgery for a complete ECD should be done in the baby's first year of life. Otherwise, lung damage that may not be able to be reversed can occur. Babies with Down syndrome tend to develop lung disease earlier. Therefore, early surgery is very important for these babies.

Outlook (Prognosis)

How well your baby does depends on:

  • The severity of the ECD
  • Your child's overall health
  • Whether lung disease has already developed

Many children live normal, active lives after ECD is corrected.

Possible Complications

Complications from ECD may include:

Certain complications of ECD surgery may not appear until the child is an adult. These include heart rhythm problems and a leaky mitral valve.

Children with ECD may be at risk for infection of the heart (endocarditis) before and after surgery. Ask your child's surgeon whether your child needs to take antibiotics before certain dental procedures.

When to Contact a Medical Professional

Contact your child's provider if your child:

  • Tires easily
  • Has trouble breathing
  • Has bluish skin or lips

Also talk to your provider if your baby is not growing or gaining weight.

Prevention

ECD is linked to several genetic variations. Couples with a family history of ECD may wish to seek genetic counseling before becoming pregnant.

Open References

References

Ebels T, Tretter JT, Spicer DE, Anderson RH. Atrioventricular septal defects. In: Wernovsky G, Anderson RH, Kumar K, et al, eds. Anderson's Pediatric Cardiology. 4th ed. Philadelphia, PA: Elsevier; 2020:chap 31.

Kliegman RM, St. Geme JW, Blum NJ, et al. Acyanotic congenital heart disease: left-to-right shunt lesions. In: Kliegman RM, St. Geme JW, Blum NJ, et al, eds. Nelson Textbook of Pediatrics. 22nd ed. Philadelphia, PA: Elsevier; 2025:chap 475.

Robbins N, Arruda J. Congenital defects of the cardiovascular system. In: Martin RJ, Fanaroff AA, eds. Fanaroff and Martin's Neonatal-Perinatal Medicine. 12th ed. Philadelphia, PA: Elsevier; 2025:chap 76.

  • Congenital heart defects (CHD) overview

    Congenital heart defects (CHD) overview

    Animation

    •  

    Congenital heart defects (CHD) overview - Animation

    Congenital heart disease describes defects of the heart or its vessels that are present at birth. They are the most common types of birth defect, affecting 1 out of every 120 babies. Some heart defects are severe, but many are not, ranging from simple defects with no symptoms, to complex defects with severe life-threatening symptoms. Each year, more than 35,000 babies in the United States are born with congenital heart defects. Most are simple defects that are easily corrected or do not need treatment. However, a small number of babies are born with complex heart defects and require special medical attention soon after birth. Over the past few decades, the diagnosis and treatment of these complex defects has greatly improved. Thanks to new and effective treatments, almost all children with complex heart defects grow to adulthood and can live active, productive lives. Most of these patients will nonetheless continue to need special heart care throughout their lives. Living with a congenital heart disease can also impact health insurance, employment, pregnancy, contraception, and the risk of infection during routine health procedures. Today, approximately 1 million American adults are living with congenital heart defects.

  • Ventricular septal defect

    Ventricular septal defect - illustration

    Ventricular septal defect is a congenital defect of the heart, that occurs as an abnormal opening in the wall that separates the right and left ventricles. Ventricular septal defect may also be associated with other heart defects. Many small defects will close on their own. For those defects that do not spontaneously close, the outcome is good with surgical repair.

    Ventricular septal defect

    illustration

  • Atrial septal defect

    Atrial septal defect - illustration

    An atrial septal defect is a congenital heart defect where the wall between the right and left atria does not close properly, leaving a hole between the two atria.

    Atrial septal defect

    illustration

  • Atrioventricular canal (endocardial cushion defect)

    Atrioventricular canal (endocardial cushion defect) - illustration

    Endocardial cushion defect is an abnormal heart condition which occurs during the development of the baby. In this condition there is no separation between the chambers of the heart. Without the separation, oxygen-rich and oxygen-poor blood mix causing the heart to work harder. Endocardial cushion defect is strongly associated with several genetic abnormalities.

    Atrioventricular canal (endocardial cushion defect)

    illustration

  • Congenital heart defects (CHD) overview

    Animation

    •  

    Congenital heart defects (CHD) overview - Animation

    Congenital heart disease describes defects of the heart or its vessels that are present at birth. They are the most common types of birth defect, affecting 1 out of every 120 babies. Some heart defects are severe, but many are not, ranging from simple defects with no symptoms, to complex defects with severe life-threatening symptoms. Each year, more than 35,000 babies in the United States are born with congenital heart defects. Most are simple defects that are easily corrected or do not need treatment. However, a small number of babies are born with complex heart defects and require special medical attention soon after birth. Over the past few decades, the diagnosis and treatment of these complex defects has greatly improved. Thanks to new and effective treatments, almost all children with complex heart defects grow to adulthood and can live active, productive lives. Most of these patients will nonetheless continue to need special heart care throughout their lives. Living with a congenital heart disease can also impact health insurance, employment, pregnancy, contraception, and the risk of infection during routine health procedures. Today, approximately 1 million American adults are living with congenital heart defects.

  • Ventricular septal defect

    Ventricular septal defect - illustration

    Ventricular septal defect is a congenital defect of the heart, that occurs as an abnormal opening in the wall that separates the right and left ventricles. Ventricular septal defect may also be associated with other heart defects. Many small defects will close on their own. For those defects that do not spontaneously close, the outcome is good with surgical repair.

    Ventricular septal defect

    illustration

  • Atrial septal defect

    Atrial septal defect - illustration

    An atrial septal defect is a congenital heart defect where the wall between the right and left atria does not close properly, leaving a hole between the two atria.

    Atrial septal defect

    illustration

  • Atrioventricular canal (endocardial cushion defect)

    Atrioventricular canal (endocardial cushion defect) - illustration

    Endocardial cushion defect is an abnormal heart condition which occurs during the development of the baby. In this condition there is no separation between the chambers of the heart. Without the separation, oxygen-rich and oxygen-poor blood mix causing the heart to work harder. Endocardial cushion defect is strongly associated with several genetic abnormalities.

    Atrioventricular canal (endocardial cushion defect)

    illustration

 

Review Date: 5/27/2024

Reviewed By: Michael A. Chen, MD, PhD, Associate Professor of Medicine, Division of Cardiology, Harborview Medical Center, University of Washington Medical School, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. No warranty of any kind, either expressed or implied, is made as to the accuracy, reliability, timeliness, or correctness of any translations made by a third-party service of the information provided herein into any other language. © 1997- A.D.A.M., a business unit of Ebix, Inc. Any duplication or distribution of the information contained herein is strictly prohibited.
© 1997- adam.comAll rights reserved.

 
 
 

 

 

A.D.A.M. content is best viewed in IE9 or above, Firefox and Google Chrome browser.
Content is best viewed in IE9 or above, Firefox and Google Chrome browser.