Ventricular Septal Defect - Treatment

Dateline: 02/15/98

Over the past month, we have discussed the concept of minimally invasive heart surgery, and the use of this novel technique in treating coronary artery disease , heart valve disease and birth defects of the heart. This week, we will go on to something different, the birth defect called Ventricular Septal Defect (VSD).

If you missed last week's article on VSD, you can read it first and come back here.

For more information on minimally invasive surgery, visit the MICAS website. And there's a lot on congenital heart disease at Heart Disease Online.

When should a VSD be repaired ?

This is yet another area where decision making is very complex. Factors to be considered are the age of the patient, size and location of the VSD, severity of lung vessel blood pressure and the degree of symptoms of heart disease.

In very small babies with severe heart failure, usually with large VSD, immediate repair usually cannot be avoided. If there is no heart failure, however, repair is postponed until six months of age. The reason for this is that a certain number of VSD's will close naturally by this time. Beyond six months, the decision to close a VSD is based on measurement of PULMONARY VASCULAR RESISTANCE - that is, the degree of damage to lung blood vessels. If the damage is less, closure is strongly recommended. If the damage is severe, repair of the VSD may actually be more harmful than not doing anything at all ! These patients have crossed the boundary of "operability".

With medium-sized VSD's, a longer waiting period is possible. If even after five to ten years the VSD has not closed, repair is justified. A special group is the VSD's that are just below the aortic valve. Because of the risk of the valve becoming "leaky" in these patients, earlier repair - before five years - is better.

NOTE: A lot of controversy still surrounds issues related to closure of VSD. The facts I have mentioned above are only currently "accepted guidelines". The decision about which treatment option is best for a particular case is best made by the physician who analyzes all the factors.

What are the ways to close VSD's ?

As always, surgical closure by an open heart operation is the "tried and tested" approach for VSD. VSD closure is by an open heart operation.Once the patient is hooked up on to the heart-lung machine, the surgeon may close the VSD by opening the right atrium or ventricle, or maybe the pulmonary artery or aorta. Rarely, when multiple VSD's are present - the so-called Swiss Cheese ventricular septum - an access through the left ventricle is preferred.

In small VSD, simple stitching of the hole with thread made of polypropylene or similar material is enough. When the defect is large, a synthetic "patch" made of a fabric like dacron or Gore-tex is used to close it. The patch is held in place using multiple sutures that pass through the rim of the VSD and then into the patch, holding it securely against the defect edges and closing it off.

Is VSD repair absolutely safe ?

Not absolutely, but yes, it is reasonably safe. Life isn't perfect after all ! Most complications are not serious. There may be excessive bleeding requiring a blood transfusion. Infection may occur and be treated by medicines. The risk of death due to operation is very low, and in most hospitals will be below 2%, except in very sick patients with a large VSD and other defects, when it is a little higher. There is however one problem that used to be seen often in older times, but which still may happen. This is an arrhythmia called HEART BLOCK.

What is heart block ? As we have seen earlier, the weak electrical current inside the heart follows a definite path. This part is marked out by CONDUCTION TISSUE - a special kind of cell designed to "conduct" or carry current. The conduction tissue of the heart passes very CLOSE to the margins of some VSD's. When stitches to repair the VSD are applied, they may injure this conduction tissue. As a result, electric impulses will not be carried normally, and will get "blocked". This is called heart block. In some cases, it will recover naturally within a week or two. But in some it does not, and needs implantation of an ARTIFICIAL PACEMAKER - a device that delivers an electric current and sets the "pace" of the heart !

How does the "VSD-repaired" patient do in the long run ?

Fortunately, very well. Most children lead normal lifestyles. Very few restrictions apply. For instance, if they have had surgery through an incision through the middle of the chest, that has split the breast-bone, they are limited from playing rough contact sports for fear of breaking the weak bone. If a synthetic "patch" has been used to close the VSD, some medicines may need to be taken for the first few weeks after operation to prevent blood clotting on the patch. Even later on, before some minor operations or medical tests - like before having a tooth removed - some medicines called ANTIBIOTICS may need to be taken for a day or two, to decrease the risk of infection on the patch. During any illness in the future, don't forget to mention to the doctor that a patient has had operation for a VSD ! Other than this, VSD-repaired patients have an almost normal life.

For more information on minimally invasive surgery, visit the MICAS website. And there's a lot more on congenital heart disease at Heart Disease Online.