Long QT syndrome

Last updated: December 1, 2022

Summarytoggle arrow icon

Long QT syndrome (LQTS) is a congenital or acquired heart condition in which the QT interval (i.e., ventricular depolarization and repolarization) is prolonged. Most patients with LQTS are asymptomatic, but some present with seizures, syncope, or even life-threatening arrhythmias and sudden death. Treatment depends on the underlying cause: Beta blockers and implantable cardioverter defibrillator (ICD) insertion are commonly used for congenital LQTS, whereas treatment of the underlying cause (drug, electrolyte abnormality, etc.) is the first-line therapy for acquired LQTS.

Etiologytoggle arrow icon

A prolonged QT interval may be congenital or acquired.

Congenital LQTS

Acquired LQTS [7][8][9][10]

Compared to other class III antiarrhythmics, amiodarone uncommonly causes torsades de pointes.

Clinical featurestoggle arrow icon

Diagnosticstoggle arrow icon

Treatmenttoggle arrow icon

All treatment modalities aim to reduce the risk and severity of cardiac events.

Complicationstoggle arrow icon

We list the most important complications. The selection is not exhaustive.

Referencestoggle arrow icon

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