(Cardiac Cath, Coronary Arteriogram, Coronary Angiogram)
What is cardiac catheterization?
Cardiac catheterization is performed to further diagnose coronary artery disease, valvular heart disease, congestive heart failure, and/or certain congenital (present at birth) heart conditions, such as atrial septal defect or ventricular septal defect, when other less invasive types of diagnostic tests indicate the presence of one of these conditions.
In cardiac catheterization (often called cardiac cath), 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 injected into the arteries.
The use of fluoroscopy (a special type of x-ray, similar to an x-ray "movie") assists the physician in the location of blockages in the coronary arteries as the contrast dye moves through the arteries. A small sample of heart tissue (called a biopsy) may be obtained during the procedure to be examined later under the microscope for abnormalities.
An additional technique called intravascular ultrasound (IVUS), a technique that uses a computer and a transducer that sends out ultrasonic sound waves to create images of the blood vessels, may be used during a cardiac cath. The use of IVUS provides direct visualization and measurement of the inside of the blood vessels and may assist the physician in selecting the appropriate treatment needed in each particular situation.
The person will remain awake during the procedure, although a small amount of sedating medication will be given prior to the procedure.
Other related procedures that may be used to assess the heart include resting or exercise electrocardiogram (ECG or EKG), Holter monitor, signal-averaged ECG, chest x-ray, computed tomography (CT scan) of the chest, echocardiography, electrophysiological studies, myocardial perfusion scans, radionuclide angiography, magnetic resonance imaging (MRI) of the heart, and ultrafast CT scan. Please see these procedures for additional information.
Reasons for the Procedure
A cardiac catheterization may be performed to assist in the diagnosis of the following heart conditions:
atherosclerosis - a gradual clogging of the arteries over many years by fatty materials and other substances in the blood stream
cardiomyopathy - an enlargement of the heart due to thickening or weakening of the heart muscle
congenital heart disease - defects in one or more heart structures that occur during formation of the fetus, such as a ventricular septal defect (hole in the wall between the two lower chambers of the heart)
congestive heart failure - a condition in which the heart muscle has become weakened to an extent that blood cannot be pumped efficiently, causing buildup (congestion) in the blood vessels and lungs, and edema (swelling) in the feet, ankles, and other parts of the body
valvular heart disease - malfunction of one or more of the heart valves that may cause an obstruction of the blood flow within the heart
A cardiac catheterization may also be performed if you have recently had an episode(s) of one or more of the following cardiac symptoms:
chest pain or angina
shortness of breath
If a screening examination such as an ECG or stress test suggests a possibility of some type of heart disease process that needs to be explored further, a cardiac cath may be ordered by your physician.
Other reasons for a cath procedure include evaluation of myocardial perfusion (blood flow to the heart muscle) if chest pain or angina occurs after the following:
heart bypass surgery
coronary angioplasty (the opening of a coronary artery using a balloon or other method) or placement of a stent (a tiny expandable metal coil placed inside an artery to keep the artery open)