Certain types of arrhythmias or heart diseases appear to have a genetic basis or run in families. This means that a family member with the disease can pass this on to his or her children. Furthermore, some family members may appear to be normal but still carry the gene for a disease and can pass this on to their children. Recently, abnormalities or defects in specific genes have been identified as the cause of certain heart diseases and arrhythmias. Although not commercially available, genetic testing for certain heart diseases is available at the University of Chicago through the laboratory of Dr. Elizabeth McNally.
Genetic counseling is also available for patients with the disease and their family members.
One such disease, the long QT syndrome, is of particular interest in this laboratory. Symptoms can be mild or severe. The normal heartbeat originates from a spot in the right upper chamber of the heart called the sinus node. The normal heart rate varies with age with faster rates occurring normally in younger children. This is especially common in younger children and is considered normal.