II. Indications
- Ventricular Arrhythmia
-
Atrial Fibrillation Cardioversion (or Atrial Flutter)
- Time to Cardioversion: 3-6 hours
- Conversion Rate: 20-52%
- Chronic Efficacy: 50-60%
III. Mechanism
- Class III Antiarrhythmic
- Prolongs Action Potential duration
- Prolongs cardiac tissue refractory period throughout heart Muscle
- Class II Antiarrhythmic
- Non-selective Beta Blocker
IV. Precautions
- Proarrhythmic with risk of Torsades de Pointes
- Initiate in monitored setting capable of cardiac Resuscitation
- Monitoring
- Telemetry
- Renal Function (GFR)
V. Dosing
- Precautions
- Different formulations (Betapace, Betapace AF and Sotylize solution) are NOT equivalent
- Adjust dose in Renal Insufficiency
- Ventricular Arrhythmia (Betapace, Sotylize)
- Start 80 mg orally twice daily
- Target: 80-160 mg orally twice daily
- Maximum: 640 mg per day (Betapace), 320 mg/day (Sotylize)
-
Atrial Fibrillation Rhythm Control (Betapace AF, Sotylize)
- Start 80 mg orally twice daily
- Target: 80-160 mg orally twice daily
- Maximum: 640 mg per day (Betapace AF), 160 mg/day (Sotylize)
VI. Adverse Effects
- Hypotension
-
Torsades de Pointes
- Associated with doses over 320 mg per day
- Higher risk in Congestive Heart Failure and female gender
VII. Safety
- Pregnancy Category B
- Avoid in Lactation
VIII. Resources
IX. References
- Olson (2020) Clinical Pharmacology, Medmaster Miami, p. 78-9
- Hamilton (2020) Tarascon Pocket Pharmacopoeia