NRS 440 Exam-Antiarrhythmics

  1. Procainamide (procan SR):
    • Class I-A (fast sodium channel blockers)
    • -Slows rate of impulse conduction in atria and ventricles. Depresses myocardial contractility, excitability and prolonging the refractory period. Widens QRS >25%. Can be given IV, IM, or PO for Vent tachycardia & Vent Fibrillation.

    Adverse effects:
    Severe immunologic reactions-lupus, neutropenia, cardiotoxicity, GI symptoms, hypotension
  2. Lidocaine (xylocaine)
    Class I-B

    • -Increases electrical threshold of ventricle during diastole, suppresses automaticity in the Bundle of His Purkinje system. Used for Ventricular arrhythmias. Bolus first, then infusion. Monitor for: prolonged PR interval and widened QRS.
    • Adverse effects: drowsiness, confusion, paresthesia. [toxic effects: convulsions, resp arrest]
  3. Beta-blockers
    Class II

    -Usually used to control excessive sympathetic stimulation (decreased automaticity of SA node, decreased velocity of conduction through AV node)
  4. Amiodorone (cordurone)
    Class III (potassium channel blockers)

    • -Used for life-threatening arrhythmias, ventricular fibrillation and tachycardia.
    • Used to convert an atrial fibrillation to normal sinus. Half life 25-110 days!!! MOST TOXIC of all arrhythmias (lung/heart toxicity, vision problems)
  5. Calcium Channel Blockers
    Class IV

    -Slows SA and AV conduction. Used to slow rate in atrial flutter/fibrillation
  6. Cardiac Glycosides
    • -decreases conduction in AV node, prolongs PR interval
    • *ONLY good for A-Fib or A-Flutter and supraventricular tachycardia
  7. Cardioversion
    synchronized electrical current delivered at levels as low as 50 joules. (usually for a-fib)

    -chemical cardioversion: usually amiodorone
  8. Cardiac Ablation
    tissue is identified causing the dysrrhythmia by a catheter and it's destroyed. It is often permamant.
Card Set
NRS 440 Exam-Antiarrhythmics
Antiarrhythmic Drug classes