PCI procedure, i.e. percutaneous coronary intervention, the main process includes local disinfection, anesthesia, puncture, examination, treatment, and post-procedure care. 1. Local disinfection: choose the puncture vessel, disinfect the surrounding area, which can be enlarged to about 15 cm, and lay a cavity towel after disinfection. 2. Anesthesia: local anesthesia can be chosen to treat the operation area. 3. Puncture: insert the guidewire through the puncture site, and then send it into the sheath tube through the guidewire, remove the guidewire and the inner sheath, and leave only the outer sheath to establish the access. 4. Examination: A contrast guidewire is placed through the sheath to examine the specific stenosis site. 5. Treatment: After confirming the specific stenosis site, balloon dilatation or stenting of the lesion is performed through the guidewire and catheter. 6. Postoperative care: After the operation, stop the bleeding of the wound site, avoid too much contact with water in the early stage, and avoid too strenuous exercise. If there is hematoma or obvious pain around the wound after PCI, it is necessary to consult a doctor in time and carry out standardized treatment under the guidance of the clinician.