A coronary angiogram is an invasive test to directly visualise the arteries that supply blood to the heart. It is an invasive test, performed in a cardiac catheterisation laboratory (similar to an operating theatre). I would perform the procedure alongside a nurse, cardiac physiologist and radiographer. It is typically performed using local anaesthetic, and sedation is commonly used to ensure patients feel more comfortable. It is usually performed by inserting a small tube into an artery at the wrist, although the artery at the top of the leg can also be used. This tube is fed up to the heart, and dye (which shows up under x-rays) is injected to determine if there are any narrowings or blockages. Whilst extremely safe, this is an invasive test which does carry risk of complications, which would be discussed in detail before any proposed procedure.