CAS is the medical abbreviation for a disease and a treatment method, the English name of coronary artery spasm is Coronary Artery Spasm, and the English name of carotid artery stenting is Carotid Artery Stenting, both are medical terms, coronary artery spasm is a heart disease, and carotid artery stenting is a common treatment for carotid artery stenosis. 1, coronary artery spasm: refers to the body at rest, due to spontaneous spasm of the coronary arteries, resulting in insufficient blood supply to the heart and thus a series of clinical symptoms of the general term, the symptoms of the less severe symptoms are mostly no obvious symptoms or only weakness, mild chest tightness, if the symptoms are more serious, may appear persistent pain, dyspnea, dizziness, syncope and other symptoms, can be treated by nitrate drugs or calcium channel blockers Carotid artery stenting: If symptoms such as carotid artery sclerosis or stenosis exist, surgical or interventional treatment is usually performed clinically. Carotid artery stenting is an interventional treatment method. For patients with carotid artery stenosis over 70%, carotid artery stenting can be implanted at the stenosis site to reduce carotid artery stenosis and thrombosis and improve blood flow perfusion to organs in the carotid vascular supply area, which has a better therapeutic effect, and carotid artery stenting is a minimally invasive interventional method, which is suitable for patients of advanced age and physical condition who cannot tolerate major surgery. It is a minimally invasive interventional method for patients who are too old and physically unable to tolerate major surgery, and has a low impact on patients and a short postoperative recovery time. Therefore, CAS usually stands for the abbreviation of two medical terms, and it is necessary to determine the specific meaning of CAS according to your own situation. The presence of CAS in the test results generally indicates coronary artery spasm, while the presence of CAS in patients with carotid artery sclerosis and arterial stenosis disease usually means that carotid artery stenting is required.