Anti-arrhythmics

Question 1

Mechanism of class I anti-arrhythmias: Na+ Channel Blockers?

Answer 1

Local aesthetics

IA: Mod.block Ph.0; slow conduction; increase APD, e.g. procainamide.

IB: Min.block Ph.0; slow conduction; shorten Ph.3 repolarization, e.g. Lidocaine

Question 2

Mechanism of Lidocaine

Answer 2

sodium channel blocker

Min.block Ph.0; slow conduction; shorten Ph.3 repolarization