Coronary artery bypass grafting (CABG) uses the body’s own arteries, veins or other vascular substitutes as bypasses to divert blood flow from the aorta to the ischemic myocardium far from the coronary stenosis, improving the blood supply to the myocardium, thereby improving angina symptoms, improving heart function, improving the patient’s quality of life and extending life expectancy. Indications for coronary artery bypass grafting: asymptomatic or mild angina, but coronary angiography shows significant left main stem lesions (stenosis greater than 50%); proximal stenosis of the anterior descending and gyral branches equivalent to left main stem lesions greater than or equal to 70%; or three vessel lesions, especially in patients with abnormal left ventricular function (ejection fraction? EF less than 50%).1 Patients with stable angina with coronary artery angiography shows significant left main lesion, or stenosis greater than or equal to 70% in the proximal anterior descending branch and the proximal left gyrus branch equivalent to left main lesion; three-branch lesion with left ventricular ejection fraction less than 50%; two-vessel lesion with proximal stenosis of the left anterior descending branch and left ventricular ejection fraction less than 50%; or non-invasive examination confirms myocardial ischemia or ineffective medical therapy.2 Unstable angina Patients with unstable angina or non-Q-wave infarction who have failed medical therapy; or coronary angiography showing significant left main lesion; or proximal stenosis of the left anterior descending and gyral branches greater than or equal to 70%3 Patients with coronary artery disease with subacute left heart function, coronary angiography showing significant left main lesion or proximal stenosis of the left anterior descending and gyral branches greater than or equal to 70%; or two or three vessel lesions with proximal lesion of the left anterior descending branch 4 Patients with severe ventricular rhythm disturbances with left main or triple vessel lesions 5 Patients with progressive angina or hemodynamic abnormalities after failed percutaneous transluminal coronary angioplasty (PTCA) 6 Patients with angina who have failed medical treatment after coronary artery bypass grafting Contraindications to surgery: Patients with predominantly heart failure, insignificant anginal symptoms, diffuse coronary artery disease, left ventricular ejection fraction less than 25 Patients with predominantly heart failure, with insignificant angina symptoms, diffuse coronary artery disease, left ventricular ejection fraction less than 25%, and extensive myocardial cell necrosis are not only high-risk but also poor surgical outcomes. Patients with other untreatable advanced diseases are not suitable for coronary artery bypass grafting. Bypass material: Vein: Saphenous vein of both lower extremities, or vein of both upper forearms. Arteries: The internal mammary artery is most commonly used, but the right gastroretinal artery, the radial artery, and the inferior abdominal wall artery can also be used as arterial bypass materials. Artificial vascular substitutes: rarely used in clinical practice.