Anti- Arrhythmic Drugs Flashcards
Name the 4 types of Anti-Arrhythmic drugs
Class I Class II Class III Class IV
Name the 3 types of Class I Anti-Arrhythmic drugs
IA IB IC
Give an example of a Class IA drug
Disopyramide
Give an example of a Class IB drug
Lignocaine
Give an example of a Class IC drug
Flecainide
Give an example of a Class II drug
Metoprolol
Give an example of a Class III drug
Amiodarone
Give an example of a Class IV drug
Verapamil
What is the mechanism of Class IA drugs
ALL CLASS 1 - Block Voltage – activated Na+ channels with preference to the most active ones (in tachyarrhythmic areas Target (T) – Voltage-activated (V/A) Na+ channel, Moderate rate of dissociation. Slow rate of rise of AP, prolonged refractory period
Variable action on action the His-Purkinje
system
What is the mechanism of Class IB drugs
ALL CLASS 1 - Block Voltage – activated Na+ channels with preference to the most active ones (in tachyarrhythmic areas T – V/A Na+ channel, Fast rate of dissociation. Prevents premature beats
Variable action on action the His-Purkinje
system
What is the mechanism of Class IC drugs
ALL CLASS 1 - Block Voltage – activated Na+ channels with preference to the most active ones (in tachyarrhythmic areas T – V/A Na+ channel, Slow rate of dissociation. Depress conduction
Variable action on action the His-Purkinje
system
What is the mechanism of Class II drugs
β-adrenoceptor (as antagonists) ↓rate of depolarisation in SA and AV nodes
Increase AV node refractory period
What is the mechanism of Class III drugs
T – V/A K+ channels Prolong AP duration, ↑ refractory period
Increase both AV node and His-Purkinje refractory period
What is the mechanism of Class IV drugs
T – V/A Ca2+ channels, ↓ force of cardiac contraction
Increase AV node refractory period
What part of the potentials do each of the classes of Anti-Arrhythmic drugs work on
