Typically, a CTA or coronary angiogram can be performed to determine if collateral circulation has been established in the heart. CTA, or CT angiography, is a non-invasive vascular imaging technique.CTA is performed by injecting a contrast agent into a vein and then using a CT device to image the blood vessels, thus determining whether collateral circulation has developed in the heart. Currently, CTA is a commonly used non-invasive method for screening for cardiovascular disease. In addition, coronary angiography is currently a common and accurate method of evaluating the alignment of blood vessels and is an accurate and effective invasive test. It can accurately determine whether there is side branch circulation formation in the heart, and also evaluate the cardiac function. Currently, CTA and coronary angiography are the most commonly used clinical methods for cardiovascular examination. These methods can be used to determine whether collateral circulation has been established on the advice of a physician.