Vagus Nerve Stimulation for Autonomic Modulation After Coronary Artery Bypass Graft Surgery

The objective of this randomized clinical trial is to investigate whether transcutaneous auricular vagus nerve stimulation (taVNS) can improve the recovery of patients undergoing coronary artery bypass grafting (CABG) through autonomic modulation, while also evaluating the safety of the intervention. The main questions this study aims to answer are: * Does taVNS improve autonomic modulation, as assessed by heart rate variability, in patients undergoing CABG? * Does taVNS reduce the inflammatory response and pain intensity while improving quality of life and functional capacity during the postoperative period? * Is taVNS a safe and well-tolerated intervention during recovery after CABG? The researchers will compare taVNS with a control group (sham stimulation/placebo) to determine whether the intervention leads to better clinical and functional outcomes in patients undergoing coronary artery bypass grafting. Participants will: * Receive sessions of transcutaneous auricular vagus nerve stimulation (taVNS) or sham stimulation (placebo), according to the study randomization. * Undergo assessments of autonomic modulation using heart rate variability before and after the intervention. * Be evaluated for inflammatory markers, pain intensity, quality of life, and functional capacity at different time points during the postoperative period.