Intravenous Magnesium Infusion in Patients Undergoing Cardioversion of Atrial Fibrillation Trial

Not Applicable

Completed

Conditions: Atrial Fibrillation

Interventions: Other: Placebo
Drug: Magnesium Sulfate

Registration Number: NCT01597557

Lead Sponsor: State University of New York at Buffalo

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

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 261

Inclusion Criteria

Patient with new onset Atrial fibrillation less than 48 hours after onset undergoing electrical cardioversion.
Patients with atrial fibrillation longer than 48 hours on warfarin with documented therapeutic INR levels >2 for at least 3 weeks prior to the cardioversion, or been on dabigatran for 3 weeks, or a transesophageal echocardiogram on the day of the procedure that excludes intracardiac thrombi, undergoing electrical cardioversion.

Exclusion Criteria

Creatinine >2.0 mg/dl
Potassium level less than 3.5 mmol/dl
TSH < 0.5
Magnesium levels >3.0 mg/dl
Urgent need for cardioversion (e.g., hemodynamic instability, unstable angina, pulmonary edema)
Patients with recent (less than 6 weeks) acute myocardial infarction
Patients post-cardiac surgery
Pregnant women
Patients who are being treated with antiarrhythmic drugs who have received less than five doses of the drug. For amiodarone, patients who have received less than three weeks prior to cardioversion are excluded.

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Placebo	Placebo	Patients in this arm receive normal saline drip intravenously before the cardioversion procedure
Magnesium Sulfate	Magnesium Sulfate	Patients in this arm are give magnesium sulfate 2 grams intravenous drip before the cardioversion procedure

Primary Outcome Measures

Name	Time	Method
Number of Participants With Successful Cardioversion of Atrial Fibrillation to Sinus Rhythm	One hour after cardioversion	Successful cardioversion involves conversion of atrial fibrillation to sinus rhythm and maintenance of sinus rhythm for one hour

Secondary Outcome Measures

Name	Time	Method
Total Amount of Energy Required for Successful Cardioversion of the Atrial Fibrillation to Sinus Rhythm	One hour
Number of Participants Who Experienced Severe Hypotensive Episodes After Infusion of Magnesium Sulfate or Placebo	30 minutes	Severe hypotensive episode with a Systolic BP \< 90mm hg with \> 20 mm Hg drop after infusion of the study drug or placebo