Diagnostic procedure to clearly visualize the renal artery anatomy. A catheter is inserted into the arterial system and advanced to the kidney(s). The tip of the catheter is placed in front of the left and then the right renal arteries. Contrast "dye" is injected into the artery as X-ray motion pictures are recorded. Recordings are done at various angles to the kidneys, to clearly define each vessel. Procedure length of time is approximately 30 minutes. Usually you may eat and drink after the procedure, when awake. For those patients that have significant renal stenosis (>70%), an renal stent can be placed in the blocked renal artery. This procedure may or may not take place at the time of the renal arteriogram based upon different variables. Your physician will make this decision after completion of the diagnostic arteriogram. Those patients that do have an renal stent placed, they will be admitted to the hospital for overnight observation.