Smoking may lead to re-obstruction of the arteries and is not conducive to recovery. It is recommended to stop smoking. Cardiac bypass grafting is used in the treatment of myocardial infarction and partially unstable angina pectoris. The most important cause of atherosclerosis is smoking. The substances produced by burning tobacco enter the human body and damage the endothelium of blood vessels, leading to atherosclerosis. As the atherosclerotic plaque gradually increases in size, it can cause blood vessel obstruction leading to myocardial infarction. Coronary artery surgery can only solve the infarction that has occurred, but not prevent it. Smoking on the one hand may lead to new blood vessel narrowing or obstruction, resulting in recurrence of the disease; and due to the stimulation of nicotine, nicotine and other substances, it will have a certain impact on the heart function, which is not conducive to the recovery of the disease. Therefore, smoking is absolutely prohibited after a heart attack. Daily recommended heart bypass patients with coronary heart disease should quit smoking and drinking in time, under the guidance of the doctor for standardized treatment, so as to avoid delaying the condition.