Ventricular Septal Defects
A ventricular septal defect (VSD) is a hole between the two pumping chambers of the heart. The result of such a hole is that some of the blood returning from the lungs, which should be pumped to the body, is instead pumped back to the lungs. The effects of a VSD depend quite a lot on the type of VSD, how large the hole is, and whether there are any other problems with the heart.
If a hole is large enough, it can cause shortness of breath and poor growth in childhood, and over time it can result in permanent injury to the lungs (pulmonary vascular occlusive disease). Doctors may use medications and high-calorie formula to help children cope with these problems in infancy, but most large VSDs require surgical repair (or, rarely, repair using a catheter device without surgery) within the first year or two of life.
If the hole is small and there are no other significant heart problems, it is usually unnecessary to do anything about a VSD. One exception is the supracristal type of VSD (discussed below).
With or without surgery, the prognosis for a VSD is quite good. I believe that most children with common types of VSDs who have no other heart problems and are diagnosed and treated appropriately can expect to live normal lives.
There are a number of differently types of VSDs:
The most common type of VSD in babies is the "muscular VSD". The vast majority of these holes are very small and do not significantly effect the functioning of the heart. About 90% close up by themselves over the first year of life, and many close thereafter.
The next most common type of VSD is the "perimembranous VSD" or "membranous VSD" (they mean the same thing). This type of VSD can be small or large. Probably about half of perimembranous VSDs close by themselves over time or are too small to require repair. Even large perimembranous VSDs can close over time, but most large defects wind up requiring surgical repair. Small perimembranous VSDs may not ever require surgical repair, but a small fraction of children with this type of VSD may develop some narrowing under one or both of the valves leading out of the heart (double chamber right ventricle or sub-aortic stenosis), so even children with small VSDs, or VSDs that have already closed on their own, need to be evaluated from time to time.
The third type of VSD is the "supracristal VSD" or "intraconal VSD" (they mean the same thing). This type of VSD is very common in children of Asian descent. Again, it can be small or large, but very often even the small holes must be surgical repaired because one of the valves of the heart can be seriously damaged by this type of VSD over time (aortic valve prolapse).
There are several other types of VSD, but they are generally associated with multiple other heart abnormalities. Examples include an inlet VSD (generally part of an atrioventricular canal defect), anterior malalignment VSD (generally part of tetralogy of Fallot) and a posterior malalignment VSD (generally associated with coarctation or interruption of the aorta and aortic valve abnormalities).
For more information about VSDs, try some of the web links below. I cannot vouch for the contents, but with the Internet it's always a case of "browser beware".
American Heart Association - http://188.8.131.52/presenter.jhtml?identifier=1306
A good site to see a brief description of the different types of heart disease and the treatments available
Boston Children's Hospital -
Overview of ventricular septal defects
The Congenital Heart Disease Resource Page - http://www.csun.edu/~hcmth011/heart/
This site is maintained by Sheri Berger, and is a good source of many links, including the congenital heart disease "link ring" (a series of sites on a common topic).
Hendrick Health - http://www.hendrickhealth.org/healthy/00070160.html
Health Square - http://www.healthsquare.com/mc/fgmc0113.htm
Congenital Heart Disease Online Handbook
This web page contains a list of Congenital Heart Diseases. Each CHD has the medically accepted abbreviation as well as a short description and a link to detailed definitions of the disease. Some of the CHD's listed have a link to a diagram that graphically shows the disease or defect. There is also a section on surgeries used to correct some of the CHD's listed at this web site, and a section on medications used to treat CHD's.