No RCTs were identified that specifically aimed to compare intravenous magnesium with sotalol as prophylaxis for AF in patients undergoing CABG. Such a comparison does not appear to be clinically meaningful. Intravenous magnesium, compared with placebo or control, is effective in preventing postoperative AF, as confirmed by a statistically significant intervention effect based on pooled analysis of 15 RCTs. It was also found that AF was less likely to occur when a longer duration of prophylaxis was used, and the earlier that prophylaxis is started; however, this finding was associated with two RCTs that had more favourable results than the other trials, but with no clear explanation as to why. No clear relationship between dose and AF was observed, although a lower constant dose rate was associated with the lowest odds of AF.
In the base-case analysis in the economic model, magnesium sulphate prophylaxis reduced the number of postoperative AF cases at a modest increase in cost. The results of the economic analysis are highly sensitive to variation in certain key parameters. Prophylaxis is less likely to be a cost-effective option if it requires changes in admission routines that result in longer preoperative stays than would be the case without prophylaxis.