Metabolic and electrolyte abnormalities as risk factors in drug-induced long QT syndrome

Area of Science:

• Cardiology
• Pharmacology
• Molecular Biology

Background:

• Drug-induced long QT syndrome (diLQTS) is a critical adverse drug reaction.
• It is characterized by cardiac repolarisation prolongation and torsades de pointes (TdP) risk.
• The human ether-à-go-go-related gene (hERG) potassium channel is a primary target.

Purpose of the Study:

• To review the clinical occurrence of diLQTS.
• To discuss factors modifying hERG channel potency and proarrhythmic risk.
• To elucidate the mechanisms of these modifications.

Main Methods:

• Literature review of drug-induced long QT syndrome.
• Analysis of environmental and disease-related modifying factors.
• Examination of molecular mechanisms affecting hERG channel function.

Main Results:

• hERG channel blockade is central to diLQTS.
• Febrile temperatures, pH changes, and electrolyte imbalances (hypokalemia, hypomagnesemia) alter risk.
• Drug-drug interactions can synergistically increase proarrhythmic potential.

Conclusions:

• Understanding modifying factors is crucial for managing diLQTS.
• These factors influence hERG channel function and patient susceptibility.
• Personalized risk assessment is needed to mitigate TdP events.