Atrial Septal Defect (ASD)
OVERVIEW
An atrial septal defect is a hole in the wall between the two upper chambers of a patient’s heart. The condition is congenital and the defects may have started of their own during infancy or early childhood.
Large atrial septal defects which may have been standing for long can damage both - the heart and lungs, however, small defects may never cause a problem and have found incidentally. An undetected atrial septal defect for decades shortens life time of an adult, causing heart failure or high blood pressure, affecting the arteries in the lungs.
Symptoms
There are no associated signs or symptoms of atrial septal defects in many new born babies.The signs or symptoms usually started showing when they reach the age 30, but in some cases signs and symptoms may not occur until a few decades.
A few signs and symptoms of atrial septal defect are:
- Shortness of breath, especially when exercising
- Stroke
- Skipped beats or Heart palpitations
- Frequent lung infections
- Fatigue
- Swelling of legs, feet or abdomen
- Heart murmur
Causes
Congenital Heart defects arise from errors in the heart's development at the early stage, but often the clear cause is missing. Genetics and environmental factors may play a role.
When the atrial septal defect is large, extra blood volume can overfill the lungs and overwork the heart. Untreated for long, the right sides of the heart eventually gets enlarged and weakened. Chances are there that the blood pressure in lungs increases as well, leading to pulmonary hypertension.
Types:
Atrial septal defects can be several types:
- Secundum - Occurs in the middle of the wall between the atria.
- Primum - Occurs in the lower part of the atrial septum. This may occur with other congenital heart problems as well.
- Sinus venosus - Occurs in the upper part of the atrial septum.
- Coronary sinus – In this defect, part of the wall between the coronary sinus and the left atrium is missing.
Treatments
Generally, many atrial septal defects close on their own during childhood; some small atrial septal defects don't cause harm and may not require any treatment. But many persistent atrial septal defects eventually require surgery to be corrected.
Medical monitoring
A child cardiologist may recommend monitoring of the child with an atrial septal defect for a period of time, to see if it closes on its own. When the child needs treatment, the doctor will decide depending on child's condition.
Medications
Medications do not repair the hole, but they may be used to reduce some of the signs and symptoms of an atrial septal defect. To reduce the risk of complications after surgery, drugs are generally used. Medications may also be used to keep the heartbeat regular or to reduce the risk of blood clots.
Surgery
Any doctor recommending repairing of an atrial septal defect diagnosed during childhood means it is aimed at preventing complications as an adult. A surgery is oftenrecommended to repair medium- to large-sized atrial septal defects. However, in case of patient with pulmonary hypertension, a surgery is not recommended.
Atrial septal defects can be repaired using two methods:
Cardiac catheterization - Doctors insert a thin catheter into a blood vessel in the groin and guide it to the heart using imaging techniques. Through the catheter, doctors set a mesh patch or plug into place to close the hole. The heart tissue grows around the mesh, permanently sealing the hole.
Open-heart surgery – The surgery is done under general anesthesia and requires the use of a heart-lung machine. Through an incision in the chest, surgeons use patches to close the hole.
