1 What is Atrioventricular Canal Defect?

Atrioventricular canal defect is a group of closely associated heart disorders that cause a defect in the center of the heart.

The defect may be in the valves or present in the form of a hole in the septum between the chambers.

It is also called endocardial cushion defect or atrioventricular septal defect. This condition is common in children with Down syndrome.

Defects can be corrected by surgery, which is usually conducted within first six months of life.

It is congenital and children with this defect have difficulty in breathing and restricted growth.

If left untreated, the defect may lead to heart failure and high blood pressure. 

2 Symptoms

It is important to be aware of symptoms of Atrioventricular Canal Defect, because they are similar to symptoms of other conditions.

Atrioventricular defect may be partial or complete.

Complete canal defect is more common than partial defect, and is characterized by a hole in the region where the upper and lower septum meet. Thus, blood may flow in all directions in the heart.

In partial defect, either the atrial septum or the ventricular septum is affected.

Both the conditions are characterized by extra flow of blood to the lungs.

Complete canal defect is characterized by symptoms like

  • Rapid breath rate
  • Difficulty in breathing
  • Lack of appetite
  • Reduced weight gain
  • Pale color of skin
  • Discoloration of lips and skin
  • Excessive sweating
  • Wheezing
  • Swelling in ankles and feet

Symptoms of complete canal defect appear in the first few weeks of life.

Symptoms of partial canal defect usually appear in adulthood and is mostly due to the complications associated with the defect.

Some common symptoms of partial defect include

3 Causes

The actual cause of Atrioventricular canal defect is not known. The defect develops before birth when the heart is developing in the fetus. In partial defect, there is a hole in the wall that separates the two upper chambers, atria. It is often associated with mitral valve defect or leakage of mitral valve that separates the atria from the ventricles.

In complete defect, there is a hole in the center of heart where the atrial and ventricular wall meets. This results in mixing of oxygen-rich and oxygen-poor blood. There is only one valve between the atria and ventricles. It results in enlargement of the heart and the organ works harder to pump blood.

The main risk factors for atrioventricular canal defect include

  • Down syndrome
  • Rubella infection
  • Alcohol use and smoking during pregnancy
  • Diabetes during pregnancy
  • Certain medications taken during pregnancy
  • Parent with a history of congenital heart defect

4 Making a Diagnosis

Atrioventricular canal defect is diagnosed in the fetus during pregnancy using ultrasound and other imaging techniques.

Abnormal whooshing sound of the heart beat in the childs heart during the first few weeks of life indicates abnormality in the functioning of heart as in atrioventricular canal defect.

ECG traces the electrical activity of the heart, while echocardiogram produces visuals of the heart while it is functioning. It helps to locate hole, an abnormality in the heart valves, and the difference in the blood flow in the heart.

Chest x-ray obtains images of the heart and helps in the identification of heart enlargement.

Cardiac catheterization is a procedure in which a small tube is inserted into the blood vessel and guided to the heart. A dye injected into the blood vessel helps to visualize the different structures of the heart and the blood vessels.

5 Treatment

Surgery is the most common treatment suggested for Atrioventricular canal defect. In this surgical procedure, the hole is closed with a patch. The lining of the heart start growing over the patch and becomes a part of the organ.

In surgical repair of partial atrioventricular septal defect, the mitral valve is repaired. If the valve is beyond repair, it is replaced with a new one.

In the treatment of complete atrioventricular septal defect, the single valve between the atria and ventricles is separated into two halves. The separated valves are then present on either side of the repaired septum. Replacement of valve is recommended if the valves cannot be separated into two halves.

Lifelong follow-up is needed after a surgical repair of the septal defect. Follow-ups are generally recommended once a year or more frequently depending on the problem.

Preventive antibiotics are suggested if the child has persistent heart defects after the surgery, or has received an artificial heart valve.

Some complication of the defect like heart valve leaks may require additional surgery to treat the condition.

6 Prevention

Atrioventricular canal defect is a congenital defect and there are no standard preventive measures for the same.

If there a family history of congenital heart defects, it is better to the counselor to understand the risk of having a child with this condition.

Rubella vaccination during pregnancy reduces the risk of atrioventricular septal defect. 

7 Alternative and Homeopathic Remedies

Consult with your doctor before starting any alternative and homeopathic remedies for Atrioventricular canal defect.

Surgery is the standard treatment for atrioventricular septal defect.

Children with this defect are prone to have inadequate nutrition as they become tired while feeding.

High-calorie formula or breast milk may help to increase the calories in each ounce. 

8 Lifestyle and Coping

It is challenging for a parent to cope with a child with Atrioventricular canal defect.

Support from family and friends help to cope with the situation better.

Be familiar with

  • the diagnosis,
  • medications,
  • surgery,
  • other procedures

of the child.

Encourage the child to do what he/she is best in.

9 Risk and Complications

Common complications of Atrioventricular canal defect are:

Some children may develop complication even after the surgical procedure.

This includes

  • valve leakage,
  • narrowing of valves,
  • arrhythmia,
  • breathing difficulties. 

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