II. Indications
-
Atrial Fibrillation Chemical Cardioversion
- Consider in combination with Electrical Synchronized Cardioversion of Atrial Fibrillation
III. Contraindications
- QTc Prolongation (or QT >500 msec)
- Severe Left Ventricular Dysfunction
- Combination with Class 1a or Class III Antiarrhythmics
IV. Mechanism
- Class III Antiarrhythmic
V. Precautions
- Cardiac monitoring on starting Ibutilide
- Monitor for a minimum of 4 hours after drug administration
- Continue monitoring until QTc Interval normalizes
- Correct Electrolyte abnormalities before starting Ibutilide (and continue to monitor Electrolyte levels)
VI. Dosing
- Initial
- Weight <60 kg: 0.01 mg/kg IV over 10 min
- Weight >60 kg: 1 mg IV over 10 min
- Subsequent
- May repeat once after 10 min if not converted to sinus rhythm with first dose
- Stop infusion on conversion to sinus rhythm
VII. Adverse Effects
- Significantly proarrhythmic
- Ventricular Tachycardia or fibrillation risk: 1-2%
- Requires EKG monitoring for 4 hours after dose
-
Prolonged QTc
- Risk of Torsades de Pointes
- Observe in monitored setting
VIII. Efficacy
-
Atrial Fibrillation Cardioversion
- Time to Cardioversion: 1 hour
- Conversion Rate: 33-45% (60% in Atrial Flutter)
IX. Safety
- Unknown safety in Lactation
- Pregnancy Category C
X. Resources
- Ibutilide Injection Solution (DailyMed)
- Ibutilide (Stat Pearls)