Coronary artery bypass graft (CABG) surgery performed via sternotomy (incision of the breastbone) can cause severe pain after surgery; this can slow recovery and increase the need for opioid pain relievers. This study investigates whether placing a catheter to deliver a local anesthetic to the superficial parasternal intercostal plane reduces pain following this type of heart surgery. Patients undergoing CABG via sternotomy will be randomly assigned to either the catheter-based analgesia group or the standard pain management group. The researchers will compare postoperative pain levels and analgesic medication requirements between the two groups to determine whether this technique improves postoperative pain control.