Cardio Exam 2: Anti-Arrhythmics Elsaid WRITTEN NOTES

What meds worsen AV block?

BBs and Non-DHPs

Class I Drugs MOA

V-G Sodium channel blocker in fast tissues

Class I Drugs ECG Effect

QRS prolongation

What are the Class IA drugs?

Quinidine and Procainamide

Quinidine is a _____ drug

Class IA

Procainamide is a _____ drug

Class IA

Class IA MOA?

Intermediate Sodium and Potassium blockade

Class IA ECG effects?

Increases QRS and QT

Drugs that cause Torsades De Pointes?

Class IA and Class III

What are the Class IB drugs?

Lidocaine and Mexiletine

Class IB MOA?

Fast sodium channel blockade of inactivated channels

Class IB ECG effects?

Decreases QT and no significant change to QRS

Lidocaine is a _____ drug

Class IB

Mexiletine is a _____ drug

Class IB

Class IB other info

selective for Ischemic myocardium and safe in long QT syndrome

What are the Class IC drugs?

Flecainamide and Propafenone

Flecainamide is a ______ drug.

Class IC

Propafenone is a ______ drug.

Class IC

Class IC MOA?

Strong Sodium blockade with prolonged binding (slowest dissociation speed)

Class IC ECG Effect?

Greatly increases QRS

Class IC other info?

Use for SVT and A. fib.

What are the Class II drugs?

Esmolol and Sotalol

Esmolol is a _____ drug.

Class II

Sotalol is a _____ drug.

Class II and III

Class II MOA?

Beta-1 receptor blockade and decreases HR and AV conduction

Class II ECG effects?

Increases PR interval

Class II Other Info?

Use for A. fib. and Re-Entry Tachycardia

Esmolol MOA?

beta-1 selective with ultra short half-life

Esmolol Uses?

Surgical/Post-Op Arrhythmia and HTN

Sotalol MOA?

Non-Selective BB and Potassium blocker

Sotalol Effects?

Decreases HR and Increases ERP, PR, and QT

What are the Class III drugs?

Amiodarone, Dronedarone, Sotalol, Ibutilide, Dofetilide, and Bretylium

Class III MOA?

Potassium channel blocker

Amiodarone and Dronedarone are ______ drugs.

Class III

Ibutilide and Dofetilide are ______ drugs.

Class III

Bretylium is a ______ drugs.

Class III

Class III ECG effects?

Increases AP duration, ERP, and QT interval

Amiodarone MOA?

Potassium blocker with Class I, II, and IV effects

Amiodarone Other info?

Very long half-life

Amiodarone Toxicity?

Pulmonary fibrosis, iodine = hypo/hyperThyroidism (T3/T4), and Coronary microdeposits

Dronedarone differences with Amiodarone?

Non-iodinated, shorter half-life, and less toxic

What are the Class IV Drugs?

Diltiazem and Verapamil

Diltiazem is a _____ drug.

Class IV

Verapamil is a _____ drug.

Class IV

Class IV MOA?

Non-DHPs = L-Type Calcium Blocker

Class IV targets what?

SA/AV node tissues

Class IV ECG effects?

Increases PR interval

Class IV Other info?

Used for A. Fib and Re-entry SVT

What drugs are used for SVT?

Class IC and adenosine (Acute)

What drugs are used for A. FIb?

Class IC, II, and IV

What is used for Re-Entry?

Class II (tachycardia) and IV (SVT)

Magnesium MOA?

Slows SA/AV node conduction

Magnesium ECG effects?

Minimal effect on CO

Magnesium Other Info?

Used for Torsades de Pointes

Atropine Sulfate MOA?

Anticholinergic and M2 Muscarinic Receptor Antagonist

Atropine Sulfate Other Info

Used for symptomatic bradycardia by increasing HR

Bretylium MOA?

Increases AP duration and ERP by affecting potassium currents

Bretylium Other Info?

Used for Refractory Ventricular Arrhythmias (rarely used today)

Adenosine MOA?

SA/AV node inhibitor

Adenosine Effects?

Very rapid onset, negative chronotropy (decreases HR) and dromotropy (decreases AV conduction), and vasodilation

Adenosine Other Info?

Used for Acute SVT

Digoxin MOA?

Na/K ATPase inhibitor

Digoxin Mechanism?

Na/K ATPase inhibited, then increases sodium, then decreases Na/Ca exchange, then increases calcium (SR Calcium release), then increases contractility

Digoxin effects?

Positive Inotropy (increases contractility), negative chronotropy (decreases HR), and increases vagal tone

Digoxin other info?

Most effective HR control at rest

REMEMBER

• ____ = Class IA drugs

• ____ = Class IB drugs

• ____ = Class IC drugs

• ____ = Class II drugs

• ____ = Class III drugs

• ____ = Class IV drugs

• ____ = Torsades de Pointes Treatment

• ____ = For Bradycardia

• ____ = Affects Potassium Currents

• ____ = Na/K ATPase Inhibitor + Cardiac Glycoside

• ____ = SA/AV Inhibitor for Acute SVT

QP, LM, FP, ES, -darone, Sotalol, -tilide, and Bretylium, Non-DHPs, Magnesium, Atropine Sulfate, Bretylium, Digoxin, Adenosine

REMEMBER EFFECTS

• ____ = Increases QRS

• ____ = Increases QT

• ____ = Decreases QT

• ____ = Increases PR interval

• ____ = Increases AP Duration

• ____ = Increases ERP

Class I
Class IA, IC, Sotalol, and III
Class IB

Class II and IV

Class III

Sotalol and Class III