ATRIAL SEPTAL DEFECT
 

What is ASD?
 

An ASD is a hole between the two upper chambers of the heart. Blood flows through this hole and creates a sort of short circuit of flow to the lungs. Normally, blood coming to the left sided chambers that is rich in oxygen is pumped to the whole body before it returns with less oxygen to the right sided chambers, and gets pumped to the lungs. With an ASD, some amount of blood (depending on the size of the hole) goes across the hole to cause extra flow to the lungs through the right sided chamber causing them to enlarge in size. The increased flow into the lung often causes a heart murmur from turbulence of extra flow across the lung artery outlet valve.
 

 

When does it need treatment?
 

There are different types of ASD based on the location of the hole in the upper chambers of the heart. Based on their location they are called by different names. The holes located in the centre of the wall between the two upper chambers is called a secundum ASD. These need treatment only of they are medium to large sized and cause significant extra flow to the lungs and increase the burden of work on the heart. Some holes located towards the edges of the wall between the chambers (sinus venosus ASD or primum ASD) invariably are more complex and involve the neighbouring structures such as the large veins or valves and need treatment. If the hole is in the centre and small, the lack of significant extra flow or work burden on the heart may not justify treatment and it may not negatively impact the quality of life. Tiny holes can be present in nearly 1 in 5 normal adults. These are called patent foramen ovale (PFO). Such holes are normal in babies inside the womb (foetuses) and may remain open in early childhood, and are not considered abnormal.

 

Symptoms of a medium or large sized ASD include rapid breathing, poor feeding and sweating whilst feeding, poor weight gain, recurrent lower chest infections, palpitations or breathlessness on exercise.

 

 

How is ASD treated?
 

Based on the size and location, these holes can be treated by catheterization by keyhole procedure done by Dr Khambadkone or open heart surgery that Dr Khambadkone will arrange in close partnership with cardiac surgeons. Catheterization involves insertion of a device, designed like a plug with two discs joined in the centre, made of a wire mesh woven into shape that can be delivered through a vein in the leg under general anaesthesia. Once deployed, the device stays in the heart for life, gets embedded and covered by inner layers of the heart. For a period of 6 months, patients have to take aspirin daily to reduce the risk of small clots forming on the device. Closure by an operation involves open heart surgery with the use of heart lung bypass where the surgeons close the hole by direct stitching or using a patch made of different materials. The recovery tends to take a little bit longer but the risk are acceptably low for the long term benefits of closing the hole.