There is imaging but not from a camera in the body (blood is not exactly transparent). It's a form of x-ray video with a tracer in the blood, so they can obser

There is imaging but not from a camera in the body (blood is not exactly transparent). It's a form of x-ray video with a tracer in the blood, so they can observe both the guide and the blood irrigation. The doctor will use live x-ray pictures to carefully guide the catheter up into your heart and arteries. Dye will be injected into your body to highlight blood flow through the arteries. This helps the doctor see any blockages in the blood vessels that lead to your heart. A guide wire is moved into and across the blockage. A balloon catheter is pushed over the guide wire and into the blockage. The balloon on the end is blown up (inflated). This opens the blocked vessel and restores proper blood flow to the heart. Source: https://medlineplus.gov/ency/article/007473.htm https://medlineplus.gov/ency/article/007473.htm