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Glossary · Tier 2

Long QT Syndrome

Also known as: LQTS, QT Prolongation, Prolonged QT Interval

Verified from StatPearls on 06-02-2026
Quick answer

Long QT Syndrome refers to a measurable lengthening of the QT interval on an electrocardiogram, a marker tied to ventricular depolarization and repolarization. The condition can arise congenitally or through acquired triggers, and it is relevant to drug safety because certain medications are known to influence QT duration. The verbatim source definition follows below, drawn from the National Library of Medicine (NCBI Bookshelf).

MedivaScan summary. The authoritative source quote follows below.

StatPearls definition

The QT interval on an electrocardiogram (ECG) represents the duration of the ventricular action potential, and this physiologically correlates with the duration of the ventricular depolarization and repolarization. Cardiac events and fatal arrhythmias may occur when the QT interval is prolonged either congenitally or through acquired causes. This activity reviews the causes of QT prolongation and highlights the role of the interprofessional team in its management.

National Library of Medicine (NCBI Bookshelf)View on source ›Verbatim quote. Last verified 06-02-2026.
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