Atrial Septal Defect (ASD), more commonly known as ‘Hole in the Heart’ is a Congenital Heart Disease present at birth. Atrial Septal Defect is a hole in the wall (septum) that separates the upper chambers (atria) of the heart into right and left atrium. This hole (defect) can be between 0.5 – 2 cm in diameter. Some of the oxygenated blood flows from the left atrium to the right atrium which contains blood that is poor in oxygen. This mixing increases the volume of blood in the right atrium that will be carried to the lungs for oxygenation, thus increasing the burden on the lungs to perform it’s function. Atrial Septal Defect is a common Congenital Heart Disease that can sometimes be asymptomatic in children. Atrial Septal Defect is the second most common Congenital Heart Disease (about 6 – 8% of all Congenital Heart Disease) and is more common in girls.
What are the types of Atrial Septal Defect?
Depending on the location of hole in the atrial wall, Atrial Septal Defect can be of 3 types:
- Ostium Secundum Atrial Septal Defect – In this type of Congenital Heart Disease, the Atrial Septal Defect is present in the center of the septum.
- Ostium Primum Atrial Septal Defect – This type of defect is present in the lower portion of the atrial septum.
- Slow Growth and Development – Your child might have slow mental and physical growth and development as the body’s increased demand for oxygenated blood is not met.
- Reduced Activity level – Your child’s activity level will have to be monitored as symptoms like dizziness and breathlessness with increased activity may be a problem. However, after the surgery for the closure of Atrial Septal Defect, this is not a problem any more.
- Enlargement of the right side of Heart – Due to shunting of blood from the left to the right side of the atrium, the right side of heart may enlarge over time due to increased workload.
- Pulmonary hypertension – Due to increased flow and pressure of blood in the lungs and pulmonary blood vessels, the pulmonary arteries may get diseased resulting in pulmonary hypertension.
- Tricuspid valve regurgitation – The tricuspid valve, which is the valve between the right atrium and the right ventricle stretches and does not close properly, allowing some of the blood to leak back from the ventricle to the atrium instead of allowing it to move forward.
- Irregular heart beats – Also called arrhythmias, this is a very serious problem associated with untreated Atrial Septal Defect.
- Risk of Stroke – In people with Atrial Septal Defect, a blood clot or air bubble may develop that may travel to the brain and cause stroke.Sinus Venosus Atrial Septal Defect – This type of Atrial Septal Defect is present in the upper portion of the septum.
Small Atrial Septal Defects usually close on their own as your child grows up and do not require any medical or surgical intervention as there are no symptoms. However, children who have a large Atrial Septal Defect need surgical intervention so that they can lead normal and healthy lives after the surgery. If the option of timely surgery for the closure of Atrial Septal Defect is not considered for some reason, then unfortunately your child might have to deal with some of the following consequences:
What does the surgical repair for Atrial Septal Defect involve?
Atrial Septal Defect is most commonly closed by Open Heart Surgery. Due to worsening of symptoms with age, children suffering from Atrial Septal Defect should be operated upon between 3 – 6 years of age. The term Open Heart Surgery is used for surgical procedures performed on the heart where the heart is stopped and is connected to a heart-lung machine which oxygenates the blood and circulates it throughout the body. The surgeon makes an incision in the middle of the chest through the breast bone (sternotomy) to expose the heart. The heart is stopped and it’s function is completely taken over by the heart-lung machine. The Atrial Septal Defect is either stitched (if small) or patched with a special mesh to close the hole. Once the procedure is complete, the heart is re-started and the chest incision is sutured. The Open Heart Surgery to correct Atrial Septal Defect is considered a major surgery and is performed under general anesthesia.