Conditions: Atrial Fibrillation
Keywords: Atrial Fibrillation Electrical Cardioversion Magnesium Sulfate
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 261
Healthy volunteers: no

Brief summary:
The proposed study is designed to evaluate the effect of an intravenous infusion of magnesium sulfate in facilitating successful cardioversion of atrial fibrillation and in decreasing the energy threshold (in J) required for successful cardioversion of atrial fibrillation into sinus rhythm.

Detailed description:
Patients with atrial fibrillation may suffer from disabling symptoms such as palpitations, shortness of breath or worsening heart failure. In such patients, it may be beneficial to convert their rhythm to sinus rhythm. Cardioversion can be achieved either pharmacologically or electrically. Pharmacological cardioversion is less successful acutely than electrical cardioversion and may be associated with complications such as prolongation of the QT interval and torsades de pointes (polymorphic ventricular tachycardia). Thus, cardioversion is most often accomplished electrically, using biphasic synchronized shocks of 75-200 Joules. Biphasic electrical cardioversion in atrial fibrillation has shown to be successful (i.e., converting to sinus rhythm) about 88% of the time, on average. The success rate appears to largely depend upon the duration of the arrhythmia and the presence and severity of structural heart disease.

In this study, we will evaluate the effect of intravenous magnesium sulfate on the success rate of electrical cardioversion, and also assess its effect in decreasing the energy levels needed for successful cardioversion. If the study is successful, we will have shown that a simple and inexpensive intervention can increase the success rate of electrical cardioversion, increasing the proportion of patients who can be restored to sinus rhythm. In addition, success with lower energy levels may improve the safety of cardioversion, as high energy levels are more likely to be associated with side effects

Arms:
arm 1: Patients in this arm are give magnesium sulfate 2 grams intravenous drip before the cardioversion procedure arm 2: Patients in this arm receive normal saline drip intravenously before the cardioversion procedure

Interventions: intervention 1: Magnesium Sulfate intervention 2: Placebo
Intervention descriptions: intervention 1: 2 grams intravenous drip over 30 minutes intervention 2: Normal Saline 50 ml intravenous drip over 30 minutes

Protocol document: