Coronary angiography is an invasive diagnostic method in which a small amount of contrast is injected through the coronary arteries and visualized under x-ray. It is an invasive diagnostic method and generally carries certain risks. There is a risk of allergic reaction with the contrast agent, or bleeding from the puncture, and there is also a risk of vasovagal reflex, nausea, vomiting, low blood pressure, causing cardiac vascular plaque detachment, or causing some liver or kidney impairment, but these cases are generally rare. This is a very mature test that has been widely used in clinical practice. The risk of coronary angiography alone is very low, just like when you cross the road, there are usually very few dangerous situations.