Long QT Syndrome Clinical Trials 2026 — Find Recruiting Studies

About Long QT Syndrome

Long QT Syndrome is a cardiac channelopathy characterised by prolongation of the QT interval on the electrocardiogram, reflecting delayed myocardial repolarisation, which predisposes affected individuals to life-threatening ventricular arrhythmias, particularly torsades de pointes, syncope, and sudden cardiac death. The three most common genetic subtypes, LQT1 (KCNQ1), LQT2 (KCNH2), and LQT3 (SCN5A), account for approximately 75% of genotype-positive cases and have distinct arrhythmia triggers and pharmacological treatment implications. Jervell and Lange-Nielsen syndrome, the autosomal recessive form involving biallelic KCNQ1 or KCNE1 mutations, additionally causes congenital profound deafness.

Common Clinical Features

Syncopal episodes, often triggered by exercise or emotion Palpitations and awareness of rapid or irregular heartbeat Seizure-like episodes due to ventricular tachycardia Prolonged QTc interval greater than 450ms (males) or 470ms (females) Sudden cardiac arrest, particularly in young individuals Swimming-triggered events (characteristic of LQT1) Auditory-triggered events (characteristic of LQT2) Nocturnal events (characteristic of LQT3)

Clinical Trial Eligibility Tips

What to know before applying to Long QT Syndrome trials.

Genetic subtype (LQT1, LQT2, LQT3, etc.) determines eligibility for subtype-specific pharmacological trials; confirm your genotype with a cardiac genetics specialist.

Baseline QTc measurement under controlled conditions (off QT-prolonging medications) is a standard eligibility benchmark; bring a resting 12-lead ECG performed without confounding drugs.

A full list of current and recent medications is essential; QT-prolonging drugs commonly exclude participation or require washout periods before screening.