Prolonged QT syndrome and sedation: a case report and a review of the literature.

Prolonged QT syndrome is the most common genetic arrhythmia syndrome, and the majority of patients are undiagnosed. The syndrome is characterized by abnormally long ventricular repolarization (QT interval) on electrocardiogram, which may manifest as syncopal episodes, arrhythmias, or sudden death. Arrhythmias may be precipitated by stress or medications.