In cardiac catheterization a very small hollow tube, or catheter, is advanced from a blood vessel in the groin or arm through the aorta into the heart. Once the catheter is in place, several diagnostic techniques may be used. The tip of the catheter can be placed into various parts of the heart to measure the pressures within the chambers.
The catheter can be advanced into the coronary arteries and a contrast dye is then injected and is photographed with X-ray to guide the catheter to the affected area to be examined. From the digital pictures of the contrast material, the doctors can tell the location and severity of the occlusion (blockage).
Angioplasty, percutaneous (through the skin) coronary intervention, and stenting may be done as part of, or following, a catheterization. The patient remains awake during the procedure, although a small amount of sedating medication is given prior to the procedure to ensure the patient remains comfortable. Cardiac catheterization rarely causes serious complications.
Watch this video on cardiac catheterization.