Coronary CT is a non-invasive test that shows whether there is a lesion in the coronary arteries by taking CT pictures and simulating the coronary system through digital imaging, and it is a non-invasive test to determine whether there is a stenosis in the coronary arteries by CT scan. However, it is only a means of examination and cannot be treated even if a lesion is found. Coronary angiography can detect coronary artery lesions and is the gold standard for coronary artery disease examination. During the dynamic examination, the site and degree of stenosis of the heart vessels and the blood supply of the whole vessels can be clearly detected. It is an interventional examination, a surgical procedure with certain risks, but it is more accurate in determining the degree of coronary lesions and can eliminate coronary stenosis by intracoronary stent implantation after lesions are detected. If there is no obvious abnormality in coronary CT examination, there is no need to do coronary angiography again; if narrowing is found in coronary CT, coronary angiography needs to be performed again to clarify the degree and location of coronary stenosis.