Ventricular septal defects (VSD) are located between the lower chambers or ventricles of the heart which pump blood to the body. Ventricular septal defects can be located in several different sections of the wall between the lower chambers of the heart. Some have a good chance of closing on their own (for example, those that are called muscular ventricular septal defects) whereas others do not close spontaneously. VSD vary from small holes, which may cause a heart murmur but no symptoms, to larger ones that cause symptoms early in life. These usually develop when an infant is between 6 and 8 weeks of age and include rapid breathing, difficulty feeding, sweating while eating, and slow weight gain. These symptoms are an indication of the child developing heart failure. If untreated, the child may have recurrent lung infections and increased pressure in the lung blood vessels that will eventually become permanent, leading to serious complications and possibly a shortened life span.