People who are not allergic to contrast media, have normal liver and kidney function and have coronary heart disease such as myocardial infarction and angina pectoris need to undergo cardiography. A cardiogram is an X-ray examination of the arteries inside the heart. The procedure involves injecting a contrast medium into the aorta of the heart, distributing the medium through the bloodstream to all parts of the heart, and then irradiating the heart with X-rays to fully visualize the basic shape of the heart’s blood vessels. A cardiac angiogram is only appropriate when the direction of the heart’s blood vessels is determined to be blocked, and is most commonly used to detect coronary heart disease, such as angina pectoris, myocardial infarction, and asymptomatic coronary heart disease. Cardiac imaging is not suitable for everyone, as it carries certain risks. People who are allergic to the contrast agent cannot undergo this kind of examination. Meanwhile, the contrast agent needs to be metabolized by the liver and kidneys, so patients with liver and kidney diseases need to use it with caution, and for people with diabetes mellitus and high blood pressure, the contrast agent is likely to increase the risk of kidney disease. Cardiac imaging is prone to bleeding risk, after the catheter enters the coronary artery, there is a risk of rupture of the blood vessel and cause hematoma, so people with coagulation disorders, vasospasm, thrombosis need to be carefully considered.