Long QT syndrome (LQTS) is a rare congenital and inherited or acquired heart condition in which electrical abnormality of the heart increases the risk of episodes of torsades de pointes (TdP, a form of irregular heartbeat that originates from the ventricles). These episodes may lead to fainting and sudden death due to ventricular fibrillation. Episodes may be provoked by various stimuli, depending on the subtype of the condition.
The QT interval on an ECG indicates the time the heart takes to recharge before beginning its next contraction. In LQTS, the QT interval is prolonged as the electrical system controlling the heart’s rhythms takes longer to recharge. The delay may result in dangerous heart rhythms.
Victims develop sudden, uncontrollable and chaotic heart rhythms during a triggered situation. It is a known cause of collapse and sudden death in young athletes running marathons. If not corrected within a couple of minutes, these erratic heart rhythms can cause death.
