Effect of single dose magnesium on arrhythmias in patients undergoing coronary artery bypass surgery

Area of Science:

• Cardiology
• Anesthesiology
• Pharmacology

Background:

• Arrhythmias are a common complication after coronary artery bypass surgery (CABG).
• Magnesium plays a crucial role in cardiac electrophysiology and may help prevent arrhythmias.
• Hypomagnesemia is frequently observed post-cardiopulmonary bypass.

Purpose of the Study:

• To assess the safety and efficacy of prophylactic magnesium sulfate in preventing arrhythmias in CABG patients.
• To evaluate the impact of magnesium on serum magnesium levels during the perioperative period.

Main Methods:

• A double-blind, randomized, placebo-controlled trial involving 104 CABG patients.
• Patients received either 2 grams of magnesium or normal saline post-intubation.
• Continuous Holter monitoring for 24 hours and serial serum magnesium level measurements were performed.

Main Results:

• Two patients (3.77%) in the magnesium group and five (9.8%) in the placebo group developed atrial fibrillation.
• The incidence of ventricular and supraventricular tachycardia was slightly higher in the placebo group.
• Post-ICU admission, mean serum magnesium levels were 2.1 in the magnesium group and 1.6 in the placebo group (p=0.6).

Conclusions:

• Prophylactic magnesium sulfate is relatively safe in CABG patients.
• Low magnesium levels were observed in the placebo group after cardiopulmonary bypass.
• Significant benefit of prophylactic magnesium in preventing arrhythmias could not be demonstrated in this study.