It is now three days since the angiogram, I’ve removed the dressing and I managed to clean up my wrist a little.
During the angiogram, they injected a special dye into the coronary artery in my wrist with via a catheter (special tube).
Most of the bruising came from the clamp they applied to the wrist to stop the artery from rupturing.
Angiography or arteriography is a medical imaging technique used to visualize the inside, or lumen, of blood vessels and organs of the body, with particular interest in the arteries, veins, and the heart chambers. (Wikipedia)