Preoperative Oral Magnesium to Prevent Postoperative Atrial Fibrillation Following Coronary Surgery (POMAF-CS)

Post operative atrial fibrillation following coronary surgery (POAF) is a common complication that can affect 10-50% of patients. It is associated with many complications. POAF increases the postoperative length of stay and increases the cost of hospitalization.

Several studies and meta-analyzes have demonstrated the beneficial effect of intravenous magnesium (Mg), administered per-or post-operatively, in reducing the incidence of POAF. However, the effect of preoperative magnesium loading on the incidence of POAF is not yet studied.

The aim of this study is to study the effect of oral Mg, administered preoperatively, on the incidence of POAF.

Following IRB approval, 200 patients admitted for elective coronary surgery under Cardiopulmonary bypass will be included in this prospective randomized controlled trial. Patients will be allocated inn a 1: 1 ratio in 2 groups:

• Treatment group will receive preoperatively 8 tablets of Mg (3.2 g) per day, at day (-3), day (-2), and day (-1) before the day of planned coronary artery surgery.
• Control group will receive 8 tablets of placebo daily,at day (-3), day (-2), and day (-1) before the day of planned coronary artery surgery.

The anesthetic and surgical management protocols will be identical for both groups. The occurrence of POAF during the 7 postoperative days, the main outcome of the study, will be recorded, including the number of POAF episodes, their duration, recurrence, and the associated ventricular response rate. From a safety point, the occurrence of complications and the length of hospital stay will be noted.

Inclusion criteria

• Adult patients
• Coronary artery disease
• Planned coronary artery surgery
• signed informed consent

Exclusion criteria

• Preoperative supraventricular dysrhythmia including atrial fibrillation, either acute or chronic
• Left ventricular EF < 30%
• Urgent surgery
• Redo surgery
• Permanent preoperative pacemaker
• Preoperative anti arrythmia drugs classes I and III
• Post operative inotrope drugs
• Postoperative bradycardia necessitating electrosystolic pacing
• Preoperative heart rate less than 50 bpm
• documented preoperative dysthryroidism
• 2nd and 3rd degree atrioventricular bloc
• Renal failure with GFR < 30 ml/min/1.73 m²