Index
Ep Defined | Getting Started | Working in the EP Lab
Right Atrium | Right Ventricle | Left Atrium | Left Ventricule | Cardiac Conduction | Cardiac Cell Properties | Action Potential | Sympathetic or Not | Med Page
Electrograms Defined | Recording Modes | Electrode Spacing | Filters | EGM Interpretation | Arrhythmia Analysis
The Physical Lab | Tools of the Trade
Setting Up | Catheter Placement | Baseline Measurement | SNRT | Conduction Study | Arrhythmia Induction | Pacing Protocols | Ablation | Tilt Table | Secrets to Success
Bradycardia | Atrial Tach | Atrial Flutter | Atrial Fibrillation | AVNRT | AVRT | Ventricular Tachycardia
Surface ECG's | Intracardiac Questions | Med Challenge | Advanced

Study Area - Medications

  Class I: Bind to sodium channel, decrease speed of depolarization.
  Class Ia: Slow Upstroke of action potential, prolong duration of action potential, decrease conductivity, increases refractoriness.
Quinidine, Procainamide, Disopyramide
    Class Ib: Minimal effect on upstroke of action potential, shorten duration of action potential, decreases refractoriness.
Lidocaine, Phenytoin, Tocainide, Mexiletine
    Class Ic: Marked slowing of upstroke of action potential, minimal effect on action  potential duration, marked decrease in conductivity, little effect on refractoriness.
Flecanide, Encainide, Propafenone
 
 

Class II:

 

Beta blocking drugs, decrease sympathetic tone, affects mainly SA and AV nodes, affect  is indirect by blocking beta receptors.
Atenolol, Labetolol, Metropolol, Nadolol, Propranolol, Timolol

 
  Class III: Increase action potential duration.
Amiodarone, Bretylium, Sotalol, Procainamide
 
  Class IV: Calcium channel blockers, affects mainly SA and AV nodes, affect is direct because SA and AV node depolarization is controlled by slow calcium channels.
Diltiazem, Verapamil
 
  Class V: Digitalis Agents, increased parasympathetic activity
Digoxin, Digitalis
Source; Richard Fogoros, Electrophysiology Testing
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