You will be taken to a facility which is equipped with all the necessary machines and equipment. You will be made to lie down on a bed and will be given an intravenous sedative to keep you calm throughout the procedure. Your Doctor will insert a needle near your groin to reach an artery and that will be used to introduce a guide tube into the opening. Once the guide tube has entered into the artery, the needle will be removed and the tube will be made to travel the length of the artery to reach the arteries of the heart. All this is guided with the help of a fluoroscope, which is an imaging tool scanning your chest area continuously. After the guide tube has reached the heart, a catheter will be introduced into the tube in the same fashion. After the catheter has reached the heart, the guide tube will be taken out and the catheter will release an opaque dye in the blood vessel. It is at this time when the graphs will be examined more closely to check for any blockage in the arteries. The procedure is helpful as it helps to detect the blocked arteries, narrowed arteries etc.