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Updated: Jun 30, 2026
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Methods for ECG Evaluation of Indicators of Cardiac Risk, and Susceptibility to Aconitine-induced Arrhythmias in Rats Following Status Epilepticus
Published on: April 5, 2011
[Long QT syndrome]
Atsuyuki Watanabe1, Kazufumi Nakamura, Hiroshi Morita
1Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine.
Nihon Rinsho. Japanese Journal of Clinical Medicine
|July 9, 2005
Summary
Long QT syndrome (LQTS) involves a prolonged QT interval, leading to dangerous heart rhythms and sudden cardiac death. It has congenital and acquired forms, influenced by genetics, drugs, and electrolyte imbalances.
Area of Science:
- Cardiology
- Genetics
- Pharmacology
Context:
- Long QT syndrome (LQTS) is a critical condition defined by QT interval prolongation.
- LQTS increases the risk of torsade de pointes and sudden cardiac death.
- It presents as either idiopathic (congenital) or acquired forms.
Purpose:
- To delineate the diverse etiologies and classifications of Long QT syndrome.
- To highlight the genetic basis of congenital LQTS, including Jervell and Lange--Nielsen and Romano--Ward syndromes.
- To identify factors contributing to acquired LQTS, such as medications and electrolyte disturbances.
Summary:
- Congenital LQTS involves genetic mutations, with subtypes linked to deafness or normal hearing.
- Acquired LQTS results from drug interactions (e.g., quinidine, sotalol, dofetilide, antihistamines, antibiotics) and physiological factors.
- Electrolyte imbalances (hypokalemia, hypomagnesemia), CNS lesions, bradyarrhythmias, and other conditions can also prolong the QT interval.
Impact:
- Understanding LQTS subtypes and triggers is crucial for accurate diagnosis and risk stratification.
- Identifying predisposing DNA variants in acquired LQTS aids in personalized risk assessment.
- This knowledge supports the development of targeted prevention and management strategies for patients at risk of sudden cardiac death.
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