The VSD is a defect in the septum that separates left and right ventricles. Blood from the left ventricle, which is at high pressure flows across the VSD, Right ventricle and then into the pulmonary artery. This results in blood reaching the lungs at high pressure. Over a period of time, the blood vessels of the lungs undergo changes and this is called pulmonary hypertension. It is to avoid this that we close the VSD.
How does it look when a surgeon opens the chest?
We see the heart situated between the diaphragm and the collar bones, and between the lungs on either side. The right border of the heart is formed by the right Atrium. The right ventricle forms the front of the heart. The left ventricle lies under the left half of the chest and the left atrium lies behind all these chambers.
To do open-heart surgery, we connect the major veins and arteries, and thereby the patient to the heart-lung machine which takes blood out of the venous system and give it back to the aorta. This is CPB, it ensures a supply of oxygenated blood to the whole body and hence keeps the patient alive, therefore, once we know that heart-lung machine is able to maintain the patient’s cardiac output, we stop the heart by giving potassium-rich solution into the blood vessels supplying the heart muscles. This is known as cardioplegia.
Open Heart Surgery
To close this VSD, we enter through the right Atrium surgically and place a patch on this defect and attach it using stitches. When we look through the oval orifice of the Tricuspid valve we are able to locate the defect in the interventricular septum, the VSD. Through which we can see the inside of the left ventricle. This is the ventricular septal defect that has got to be closed. It is closed by placing a patch and stitching along the edges with suture material, working in the motionless heart. This is VSD closure.
The heart is then closed, all the inside air is taken out and blood is returned to the heart. It is allowed to start beating and once the heart and lung function comes back to normal, we wean the patient off the heart-lung machine and remove the tubes inserted earlier. When the child is safe, we close the chest and shift them to the ICU for care under trained doctors and nurses.
During this entire time, the patient is under anaesthesia and is not aware of any of this activity.