Long QT syndrome

A heart rhythm disorder that can potentially cause fast, chaotic heartbeats.


Long QT syndrome can be inherited or caused by a medication or condition. It often goes undiagnosed or is misdiagnosed as a seizure disorder, such as epilepsy.


Heartbeats can be so fast and for so long that they trigger a sudden fainting spell, seizure, or even sudden death.


Treatment can involve medical devices, surgery, lifestyle changes, or medications, such as beta blockers.

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