Related Experiment Video
Updated: Jul 19, 2026

Determining the Likelihood of Variant Pathogenicity Using Amino Acid-level Signal-to-Noise Analysis of Genetic Variation
Published on: January 16, 2019
Congenital long QT syndrome
Najeeb Ahmed1, Kamran Riaz, Ripudeep Rai
1Department of Internal Medicine, Wright State University Boonshoft School of Medicine, Section of Electrophysiology, Good Samaritan Hospital, Dayton, Ohio, USA.
Abstract:
Long QT syndrome (LQTS) can be asymptomatic-identifiable as an incidental finding on electrocardiogram-or it can present with palpitation, syncope, seizures, or sudden cardiac death. LQTS is characterized by a prolonged QT interval, which can be associated with a specific form of polymorphic ventricular tachycardia known as torsade de pointes. Other electrocardiogram changes in LQTS include T-wave abnormalities, particularly bifid T waves, U waves, and T-wave alternans. The precipitating factors of LQTS include electrolyte abnormalities, bradyarrhythmias, medications (such as antiarrhythmic drugs, antibiotics, antipsychotics, and antihistamines), and myocardial ischemia. The authors report a case of LQTS in a 47-year-old woman with no other significant cardiac history.
Related Concept Videos
Dysrhythmias IV: Characteristics of Bradyarrhythmias
ECG Interpretation of Arrhythmias II: Atrial, Junctional and Ventricular Arrhythmias
Mechanism of Cardiac Arrhythmias
Cardiomyopathy III: Hypertrophic Cardiomyopathy
Inborn Errors of Metabolism
Dysrhythmias I: Introduction

