Generally speaking, if all other tests are normal and there are no obvious symptoms, then coronary angiography is not necessary. However, this is not absolute. If there is a high suspicion of coronary artery disease, then even if all other tests are normal, a coronary angiogram is still needed to confirm the diagnosis of the disease. Coronary angiography is a common test that can visualize the shape and distribution of the coronary arteries to diagnose and treat coronary heart disease, angina pectoris, and severe stenosis. Generally speaking, if all other tests are normal and there are no symptoms, then coronary angiography is not necessary. It is important to know that this is a minimally invasive procedure, which may affect the patient’s health and lead to some complications, such as contrast allergy, puncture injury, kidney damage and arrhythmia. However, this is not absolute. If there is a high suspicion of coronary artery disease and there are some abnormal symptoms, such as obvious chest tightness or chest pain after activity or abnormal electrocardiograms, then it is necessary to confirm the diagnosis of the disease through coronary angiography in a timely manner. In order to reduce the risk of coronary angiography, before the official coronary angiography examination, the patient should first carry out a detailed physical examination, promptly inform the doctor of their allergies, and carry out the procedure under the guidance of the doctor.