Diagnostic procedure to clearly visualize the coronary artery anatomy. A catheter is inserted into the arterial system and advanced up to the heart. The tip of the catheter is placed in front of the left and then the right coronary arteries. Contrast "dye" is injected into the artery as X-ray motion pictures are recorded. Recordings are done at various angles to the heart, to clearly define each vessel. Procedure length of time is approximately 10-20 minutes. Usually you may eat and drink after the procedure, when awake. Procedure is usually done in conjunction with a Left Ventriculogram. Patient is restricted to bed rest for approximately 1-6 hours after the procedure. **Length of time on bed rest will vary depending on physician and if a "closure device" was used to seal the puncture site in the artery. If no closure device is used, the catheter is then removed and manual pressure is held until the bleeding has stopped. A tight pressure dressing is placed over the puncture site and will remain for several hours - approximately 6 hours and the patient will remain on bed rest during this time.