What medications are known to potentially cause torsades de pointes?

What medications are known to potentially cause torsades de pointes?

• A. Beta-blockers
• B. Antihypertensives
• C. Medications that block potassium channels
• D. ACE inhibitors

Answer: (C)

Torsades de pointes is a type of polymorphic ventricular tachycardia that is often associated with a prolonged QT interval. Medications that block potassium channels are particularly significant in this context because they interfere with the normal repolarization phase of the cardiac action potential. This disruption can lead to an increased risk of developing a prolonged QT interval, which is a known precursor to torsades de pointes.

Many antiarrhythmic drugs, certain antidepressants, and some antipsychotics are examples of medications that block potassium channels. By inhibiting the repolarization process, these drugs create an environment conducive to the development of reentrant arrhythmias, including torsades de pointes. Therefore, recognizing the role of potassium channel blockers in this potentially life-threatening arrhythmia is crucial for appropriate patient management and risk assessment.