Stenting is done in two stages, possibly due to the complexity of the lesion site, which makes the procedure more risky when performed in one go, or because of severe stenosis in both the right and left coronary arteries, which makes the risk of in-stent thrombosis in the short term higher when performed in one go. Cardiac stenting is generally indicated for people with more than 50% stenosis in major branches of the coronary arteries, such as the left main stem, and more than 70% stenosis in other branches, such as the proximal segment of the left anterior descending branch. In general, the coronary artery lesions can be clearly visualized by coronary angiography, and stenting can be performed in a single procedure to recanalize the blood vessels without the need for two separate procedures. However, the following cases may require multiple stenting. 1. Complex lesion site: When the patient’s lesion site is complex and the lesion branches are many, stent implantation in one go is risky, so the doctor usually improves the main blood vessel first, and then improves the lesions of other branches after the condition is stabilized. 2. Severe stenosis in both left and right coronary arteries: When both left and right coronary arteries have severe stenosis, if stent implantation is carried out at the same time, the risk of in-stent thrombosis will increase in the short term. In addition, if the operation time is too long, too many rays are given, and too much contrast agent is used, all of them can lead to corresponding damage. 3. Inappropriate stent size: When the hospital does not have the right type of stent for the patient, if implantation is performed, complications such as stent displacement may occur due to inappropriate size. Therefore, when you are told that the stent is done in two stages, you should trust the judgment of your professional doctor and follow the doctor’s instructions to avoid complications.