Antiarrhythmics: Difference between revisions

Latest revision as of 18:13, 14 August 2017

Table

Class	Known as	Examples	Mechanism	Clinical uses
Ia	fast-channel blockers-Affect QRS complex	Quinidine Procainamide Disopyramide	(Na⁺) channel block (intermediate association/dissociation)	Ventricular arrhythmias prevention of paroxysmal Recurrent atrial fibrillation (triggered by Vagus nerve overactivity) procainamide in Wolf Parkinson White (WPW)
Ib- Do not affect QRS complex		Lidocaine Phenytoin Mexiletine Tocainide	(Na⁺) channel block (fast association/dissociation)	treatment and prevention during and immediately after Myocardial infarction, though this practice is now discouraged given the increased risk of Asystole Ventricular tachycardia Atrial fibrillation
Ic		Flecainide Propafenone Moricizine	(Na⁺) channel block (slow association/dissociation)	prevents Paroxysmal atrial fibrillation treats Recurrent tachyarrhythmias of abnormal conduction system. contraindicated immediately post-myocardial infarction.
II	Beta-blockers	Propranolol Esmolol Timolol Metoprolol Atenolol Bisoprolol Labetalol	beta blocking Propranolol also shows some class I action	decrease Myocardial infarction mortality prevent recurrence of Tachyarrhythmias
III		Amiodarone Sotalol Ibutilide Dofetilide Dronedarone E-4031	K⁺ channel blocker Sotalol is also a β-blocker Amiodarone has Class I, II, and III activity	In Wolf Parkinson White (WPW) (sotalol:) Ventricular tachycardias and Atrial fibrillation (Ibutilide:) Atrial flutter and Atrial fibrillation
IV	slow-channel blockers	Verapamil Diltiazem	Ca²⁺ channel blocker	prevent recurrence of Paroxysmal supraventricular tachycardia reduce Ventricular rate in patients with Atrial fibrillation
V		Adenosine Digoxin Magnesium sulfate	Work by other or unknown mechanisms (Direct nodal inhibition).	Used in supraventricular arrhythmias, Or in the case of magnesium sulfate, used in torsade de pointes.

References

Katzung & Trevor's Pharmacology

Authors:

@@ Line 1: / Line 1: @@
-==Lidocaine==
+==Table==
-=== Adult Dosing ===
-*Loading dose = 1-1.5 mg/kg
+{| class="wikitable" style="width: 641px; height: 711px;"
-**Additional boluses of 0.5-0.75 mg/kg q5-10min up to max of 3mg/kg
+|-
-**If effective start infusion of 2mg/min
+! Class
+! Known as
+! Examples
+! Mechanism
+! Clinical uses
+|-
+! Ia
+| fast-channel blockers-Affect QRS complex
+|
+*Quinidine
+*[[Procainamide]]
+*Disopyramide
-=== Contraindications ===
+| (Na<sup>+</sup>) channel block (intermediate association/dissociation)
+|
+*Ventricular arrhythmias
+*prevention of paroxysmal Recurrent atrial fibrillation (triggered by Vagus nerve overactivity)
+*procainamide in [[Wolf Parkinson White (WPW)]]
-*High SA or AV block
+|-
+! Ib- Do not affect QRS complex
+|
+|
+*[[Lidocaine]]
+*Phenytoin
+*Mexiletine
+*Tocainide
-=== Indications ===
+| (Na<sup>+</sup>) channel block (fast association/dissociation)
+|
+*treatment and prevention during and immediately after Myocardial infarction, though this practice is now discouraged given the increased risk of Asystole
+*Ventricular tachycardia
+*[[Atrial Fibrillation (Main)|Atrial fibrillation]]
-*Treatment of ventricular arrhythmias and ectopy
+|-
-**Considered 2nd-line to amiodarone for tx of V-fib and pulseless v-tach
+! Ic
+|
+|
+*[[Flecainide]]
+*Propafenone
+*Moricizine
-=== Mechanism of Action ===
+| (Na<sup>+</sup>) channel block (slow association/dissociation)
+|
+*prevents Paroxysmal atrial fibrillation
+*treats Recurrent tachyarrhythmias of abnormal conduction system.
+*contraindicated immediately post-myocardial infarction.
-*Class Ib
+|-
-**Binds to fast Na channels in inactive state thereby inhibiting recovery after repolarization
+! II
-**Acts preferentially on ischemic tissue
+| [[Beta-blockers]]
-***Elevates V-fib threshold
+|
-***Suppresses ventricular ectopy
+*Propranolol
-*Little effect on vascular tone, contractility or cardiac output
+*[[Esmolol]]
+*Timolol
+*[[Metoprolol]]
+*[[Atenolol]]
+*Bisoprolol
+*[[Labetalol]]
-=== Adverse Drug Rxns ===
+| beta blocking<br>Propranolol also shows some class I action
+|
+*decrease Myocardial infarction mortality
+*prevent recurrence of Tachyarrhythmias
-*CNS
+|-
-**Abrupt change in MS, drowsiness, confusion, sz
+! III
+|
+|
+*[[Amiodarone]]
+*[[Sotalol]]
+*[[Ibutilide]]
+*Dofetilide
+*Dronedarone
+*E-4031
-=== Kinetics ===
+|
+K<sup>+</sup> channel blocker
-*Onset of action = 45-90s
+Sotalol is also a β-blocker
-*Duration of action = 10-20min
-== [[Procainamide]] ==
+Amiodarone has Class I, II, and III activity
+|
+*In [[Wolf Parkinson White (WPW)]]
+*(sotalol:) Ventricular tachycardias and Atrial fibrillation
+*(Ibutilide:) Atrial flutter and [[Atrial Fibrillation (Main)|Atrial fibrillation]]
-== [[Esmolol]] ==
+|-
+! IV
+| slow-channel blockers
+|
+*Verapamil
+*[[Diltiazem]]
-== [[Labetalol]] ==
+| Ca<sup>2+</sup> channel blocker
+|
+*prevent recurrence of Paroxysmal supraventricular tachycardia
+*reduce Ventricular rate in patients with [[Atrial Fibrillation (Main)|Atrial fibrillation]]
-== [[Sotalol]] ==
+|-
+! V
+|
+|
+*[[Adenosine]]
+*[[Digoxin]]
+*[[Magnesium sulfate]]
-== [[Amiodarone]] ==
+| Work by other or unknown mechanisms (Direct nodal inhibition).
+|
+Used in supraventricular arrhythmias,
-== [[Ibutilide]] ==
+Or in the case of [[magnesium sulfate]], used in [[torsade de pointes]].
-== [[Diltiazem]] ==
+|}
-== [[Atropine]] ==
+==See Also==
+*[[Arrhythmias (DDX)]]
+*[[Atropine]]
+*[[Isoproterenol]]
-== [[Adenosine]] ==
+==References==
+<references/>
+*Katzung &amp; Trevor's Pharmacology
-== [[Digoxin]] ==
+[[Category:Pharmacology]] [[Category:Cardiology]]
-== [[Isoproterenol]] ==
-== [[Magnesium]] ==
-=== Source ===
-Tintinalli
-<br/>[[Category:Drugs]] <br/>[[Category:Cards]]