The<unk>  <unk>  is a heart condition associated with prolongation of polarization (recovery) following depolarization (excitation) of the cardiac ventricles.  It is associated with syncope (fainting) and sudden death due to ventricular arrhythmias.  Arrhythmias in individuals with<unk>  are often associated with exercise or excitement. <unk>  is also associated with torsade de pointes, a the rare ventricular arrhythmia which can deteriorate into ventricular fibrillation and ultimately death.
Individuals with<unk>  have a prolongation of the<unk>  interval on the EKG.  The Q wave on the EKG corresponds to ventricular depolarization while the T wave corresponds to ventricular repolarization.  The<unk>  interval is measured from the beginning of the Q wave to the end of the T wave.  While many individuals with<unk>  have persistent prolongation of the<unk>  interval, some individuals do not always show<unk>  prolongation; in these individuals, the<unk>  interval may prolong with the administration of certain medications.
Long QT Syndrome
Long QT syndrome
Short QT syndrome type 1
Short QT syndrome type 3
Short QT syndrome type 2
Short QT syndrome type 4
Short QT syndrome type 5
Familial atrial fibrillation