Q: Which one intervention may decrease the risk of torsades de pointes with ibutilide?
Answer: Pretreatment with intravenous (IV) magnesium
Ibutilide is not very popular for use as chemical agent for cardioversion in acute atrial fibrillation. This is due to it's risk to cause torsades de pointes. A less known fact is that it is more effective to convert atrial flutter to sinus rhythm. Pretreatment with IV magnesium decreases the risk of ibutilide-induced torsades de pointes. Risk factors for ibutilide-induced torsades de pointes are heart failure, baseline prolong QTc interval, hypokalemia or hypomagnesemia.
The dose of Ibutilide in average adult patient is 1 mg over 10 minutes. If no or partial response, a second bolus of 1 mg over 10 minutes can be used.
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