A randomized controlled trial of intravenous magnesium sulphate as an adjunct to standard therapy in atrial fibrillation

Abstract Background Magnesium sulphate (MgSO4) has been proven as an analgesic, neuromuscular blocker agent, and treatment of acute asthma. Objective The study aimed to assess the safety and efficacy of magnesium sulphate infusion for the treatment of patients with atrial fibrillation. Methods A prospective, randomized, double-blind, placebo-controlled study was conducted on 55 atrial fibrillation patients at the Emergency Department. The treatment group consisting of 41 patients received 20 mEq (2.5 g, 10 mmol) magnesium sulphate over a 20-minute period, followed by 20 mEq (2.5 g, 10 mmol) over a 2-hour period intravenously in addition to the standard treatment, and the control group consisting of 14 patients received placebo with a standard treatment. ECG was repeated and monitored upto 24 hours after the infusion. Results 41 patients received magnesium sulphate and 14 patients received a placebo. The heart rate was 127 bpm – 210 bpm at the presentation to the emergency department and it was reached <100bpm in 70%(n=31) patients after 150 minutes of MgSO4 infusion. Two patients attained a heart rate of <100bpm in Placebo infusion. In the treatment group, 65% of subjects attained normal sinus rhythm at the end of 24 hours of infusion. Magnesium sulphate was more likely than placebo to achieve a heart rate of <100bpm and more likely to convert to sinus rhythm. ECG report reverted to normal in 74.5% in the treatment group and 25.5 % in the Placebo group within 24 hours. The patients in the treatment group stay a mean of 2.25 days in ICU, while the patients in the Placebo group stayed 4.25 days in ICU. Seven patients in the treatment group had minor side effects like flushing, headache, and nausea, which came to normal after 48hrs. Conclusions Magnesium sulphate has been shown a better efficacy to control the heart rate and conversion to sinus rhythm when used along with the standard management of Atrial fibrillation.