We are doing this study to learn more about the cause of cardiac (heart) disease or sudden unexplained death, which is something that can run in families. Some conditions that we are looking at are:

• Cardiomyopathies (a disease of the heart muscle that makes it harder for your heart to pump blood to the rest of your body) like hypertrophic cardiomyopathy, dilated cardiomyopathy, or arrhythmogenic right ventricular cardiomyopathy
• Arrhythmia syndromes (a problem with the rate or rhythm of the heartbeat, either too slow or too fast) like long QT syndrome, Brugada syndrome, catecholaminergic polymorphic ventricular tachycardia, or short QT syndrome
• Sudden cardiac arrest or unexplained sudden death (heart stops suddenly), including sudden infant death syndrome (SIDS)