Class I Antiarrhythmics MOA

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Class I Antiarrhythmics – MOA including K⁺ effects
Primary action: Block fast Na⁺ channels → ↓ phase 0 depolarization → slower conduction.
Subclass effects on K⁺ channels (phase 3 repolarization):
Class IA: Also block K⁺ channels → prolong repolarization (↑ action potential duration & QT interval).
Class IB: Minimal/no K⁺ block → actually shorten AP duration.
Class IC: Strong Na⁺ block, little/no K⁺ effect → no significant change in AP duration.

Видео Class I Antiarrhythmics MOA канала Anant`s Pharmacology