This study aims to evaluate whether daily low-dose colchicine (0.5 mg), administered in addition to the standard secondary prevention regimen recommended in clinical guidelines after coronary artery bypass grafting (CABG), can further prevent graft failure after CABG through a prospective, randomized, double-blind, placebo-controlled clinical trial.

Inclusion Criteria:

1. Be male or female, aged 18 years or older;
2. Within 3 days after successful isolated coronary artery bypass grafting (CABG);
3. Sign informed consent;

Exclusion Criteria:

1. Severe valvular heart disease requiring concomitant or staged valvular surgery;
2. History of non-skin cancer in the past 3 years;
3. Inflammatory bowel disease or chronic diarrhea;
4. Neuromuscular diseases or non-transient creatine kinase levels greater than 3 times the upper limit of the normal range (except those associated with myocardial infarction);
5. Clinically significant non-transient (At least 2 laboratory tests) blood abnormalities (Hemoglobin <100g/L or hematocrit < 30% or > 52% or white blood cell count < 3×109/L or platelet count < 100×109/L);
6. Estimated glomerular filtration rate (eGFR) < 30 mL/min/1.73 m² (based on the CKDEPI formula);
7. Serum alanine aminotransferase and/or aspartate aminotransferase levels greater than 2 times the upper limit of the normal range, accompanied by serum total bilirubin levels greater than 2 times the upper limit of the normal range or severe liver disease with coagulation disorders (INR>1.5) (except for elevated glutamic oxalacetic transaminase associated with myocardial infarction);
8. Decline in cognitive function due to inability to perform basic activities of daily living independently;
9. Drug or alcohol abuse;
10. Other immunosuppressive therapies already in existence or planned;
11. Other causes require long-term colchicine treatment;
12. History of clear or suspected colchicine allergy;
13. Strong CYP3A4 or P-glycoprotein inhibitors (such as cyclosporine, antiretrovirals, antifungals, erythromycin and clarithromycin) have been used and no other alternative drugs can be used.