Effect of Preoperative Stellate Ganglion Block on Postoperative Atrial Fibrillation After Coronary Artery Bypass Grafting

Who May Qualify: - more than 18 years old - undergoing CABG - Provide willing to sign a consent form Who Should NOT Join This Trial: - History of prior cardiac surgery or atrial fibrillation ablation; - Emergency coronary artery bypass grafting (CABG); - Concomitant cardiac procedures (e.g., congenital heart disease repair, left ventricular reconstruction, valve surgery, or aortic surgery); - Critical preoperative status requiring mechanical or pharmacological support before CABG; - Left ventricular ejection fraction (LVEF) \<35%; - History of atrial fibrillation (defined as a supraventricular tachyarrhythmia characterized by rapid and irregular atrial electrical activity); - Significant mitral valve disease (mitral valve area \<1.5 cm² or regurgitant jet area \<4 cm²), significant aortic valve disease (valve area \<1.5 cm² or regurgitant jet-to-left ventricular outflow tract ratio \>25%); - Severe left atrial enlargement (left atrial anteroposterior diameter \>55 mm); - Poorly controlled hyperthyroidism; - Conditions requiring radiotherapy, chemotherapy, or long-term hormonal therapy; - Patients with known clinical contraindications to stellate ganglion block (SGB). Always talk to your doctor about whether this trial is right for you.