An atrial septal defect (or “ASD”) is a hole between the two smaller pumping chambers of the heart. It allows blood to cross from the left chamber to the right leading to extra flow through the lung artery. Usually patients with ASD’s have very few symptoms but eventually, during later adult life breathlessness and electrical instability of the heart can develop.
There are three types of ASD’s:
Secundum ASD. This is the most common ASD, affecting around 90% of people with ASD’s. It is caused when part of the atrial septum does not close whilst the heart is developing. This results in a hole in the middle of the wall separating the two atria.
Sinus Venosus ASD. This defect occurs in the part of the atrial septum close to where a large vein enters the heart. As a result, the drainage of one or more veins may be abnormal in that the veins drain into the right atrium, rather than the left atrium.
Primum ASD. This defect occurs in the lower part of the atrial septum and often is associated with mitral and tricuspid heart valve problems.
We would generally recommend closure of all but the smallest of ASD’s, unless other problems are present that would make this unwise (for example damage to the lungs, which can occur in some patients with ASD’s). Your cardiologist will make an assessment of the hole in your heart and discuss treatment with you. If the best treatment option for you is surgery then you will meet the surgeon and nurse specialist in outpatients before your operation.
The operation is always performed under a general anaesthetic so you will be asleep. The surgeon makes an opening in the middle of the chest through the breast bone to get to the heart. During the operation, the function of the heart and lungs is taken over by a machine (“heart bypass”). The surgeon can then stop the heart and stitch the hole closed or cover it with a patch. After the operation the breastbone is closed using stainless steel wires and surgical drains (tubes) are positioned in the chest to allow any excess fluid to drain. These are normally taken out after about 24 hours. As a precaution, pacing wires are placed on the surface of the heart in case of a low heart rate (bradycardia) in the early post-operative stage, these are removed 4-5 days after the operation.
The procedure is very safe with a risk of dying of around 1 in 300. There is an even smaller risk of brain damage (stroke) related to the use of the heart bypass machine. Other minor problems can occur, such as bleeding, infection, fluid collecting around the heart or temporary electrical instability but these are rarely serious. After surgery a short stay on the intensive care unit (usually overnight) and then a period in hospital for observation (usually about 5-7 days) is required before going home. Opening the front of the chest leads to a scar and the chest wall will be sore whilst it heals. The time taken to get fully back to normal varies from person to person but can be up to 3 months.
After your operation you will be closely monitored by both the surgeon and cardiologist. A nurse specialist will visit you on the ward and provide you with discharge advice. The nurse will phone you at home in the week following discharge to check on your progress. You will be given a telephone number that you can contact should you have any concerns in between discharge and follow-up. The team’s physiotherapist can provide exercise plans. These are useful as it is important for your recovery to remain active after the operation.
In the 2 weeks leading up to your surgery, you will receive an appointment to come to see the nurse at the preadmission clinic. This is to make sure that you are fit for surgery and also to give you an opportunity to ask any questions or find out more about coming into hospital.
It is also important to make sure that all dental work has been completed within 3- 6 months prior to surgery.