Many patients ask why they need to take lipid-lowering medication after having heart bypass surgery. The incidence of reoperation after bypass surgery is 10%, and the mortality rate of reoperation treatment is 2 to 3 times higher than that of the first surgery. Therefore, medication after CABG is very important. Drug therapy stops or alleviates the progression of atherosclerosis and prevents stenosis or occlusion of the bridge vessels. Statins can lower low-density lipoprotein (LDL-C) levels, resist atherosclerosis, and reduce clinical coronary events. In addition, statins have stabilizing and even reversing atherosclerotic plaques, inhibiting inflammation at the atherosclerotic site, modulating endothelial function, and antiplatelet effects, among others. Studies have shown that in patients with myocardial infarction who have undergone revascularization, statin use significantly reduces coronary death and the incidence of fatal or nonfatal myocardial infarction, and the benefit increases the longer the statin is taken. Therefore, long-term cholesterol-lowering therapy should be maintained even more after bypass surgery so that LDL-C levels are at least <70 mg/dL, thus controlling plaque progression.