Prevention Atrial Fibrillation by BOTulinum Toxin Injections (BOTAF)

Before the main stage of the surgery, botulinum toxin will be injected into the entire visible area of the 4 major epicardial fat pads, during extra corporal circulation and before aortic cross clamping in order to reduce the time of ischemia.

All patients from the control group will receive placebo. Before the main stage of the surgery, during extra corporal circulation and before aortic cross clamping, the placebo will be injected into the entire visible area of the 4 major epicardial fat pads as follows (1 mL at each fat pad).