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Antiarrhythmic

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Antiarrhythmic, Vaughn Williams Classification, Class I Antiarrhythmic Drug, Class 1 Antiarrhythmic, Class Ia Antiarrhythmic Drug, Class Ib Antiarrhythmic Drug, Class Ic Antiarrhythmic Drug, Class II Antiarrhythmic Drug, Class 2 Antiarrhythmic, Class III Antiarrhythmic Drug, Class 3 Antiarrhythmic, Class IV Antiarrhythmic Drug, Class 4 Antiarrhythmic, Sodium Channel Blockade Antiarrhythmic, Sodium Channel Blocker Antiarrhythmic, Potassium Channel Blockade Antiarrhythmic, Potassium Channel Blocker

  • See Also
  1. Sodium Channel Blocker
  • Mechanism
  1. See Cardiac Action Potential
  2. Images
    1. CardiacActionPotential.png
  • Medications
  • Class I - Sodium Channel Blockade
  1. Background
    1. Unlike other Antiarrhythmic classes, Class I agents have minimal effect on SA Node automaticity
  2. Class Ia: Lengthens Action Potential duration
    1. Quinidine
    2. Procainamide (Pronestyl)
    3. Disopyramide (Norpace)
    4. Amiodarone (also Class II, III, IV)
    5. Several non-classic Antiarrhythmics have Class Ia activity (e.g. Imipramine, a Tricyclic Antidepressant)
  3. Class Ib: Shortens Action Potential duration
    1. Lidocaine (Xylocaine)
    2. Tocainide (Tonocard)
    3. Mexiletine (Mexitil)
    4. Phenytoin (Dilantin)
  4. Class Ic: Slows conduction
    1. Precautions
      1. Increased proarrhythmia risk and risk of Sudden Cardiac Death
      2. Avoid in structural heart disease, Coronary Artery Disease and Left Ventricular Hypertrophy
      3. Must use with concurrent AV Nodal Blocking agent (e.g. Beta Blocker)
    2. Flecainide (Tambocor)
    3. Encainide (Enkaid)
    4. Propafenone (Rythmol)
  1. Propranolol
  2. Metoprolol
  3. Atenolol
  4. Carvedilol (Coreg)
  5. Esmolol (Brevibloc)
  6. Sotalol (also Class III)
  7. Amiodarone (also Class Ia, III, IV)
  • Medications
  • Class III - Blocks potassiun channels, prolongs repolarization
  1. Bretylium (Bretylol)
  2. Sotalol
  3. Amiodarone (also Class Ia, II, IV)
  4. Dofetilide (Tikosyn)
  5. Dronedarone (Multaq)
  1. Verapamil (Calan)
  2. Diltiazem (Cardizem)
  3. Nifedipine
  4. Amiodarone (also Class Ia, II, III)
  • References
  1. Olson (2020) Clinical Pharmacology, Medmaster Miami, p. 83
  2. Helton (2015) Am Fam Physician 92(9): 793-800 [PubMed]