Cardiovascular Diagnostic Procedures
A coronary calcium scan (CCS) is a noninvasive exam which looks for specks of calcium (called calcifications) in the walls of the coronary arteries. The coronary arteries are the vessels that supply oxygen-containing blood to the heart wall. Calcium is an early sign of coronary artery disease. The calcium score gives an idea of whether coronary artery disease is present despite a lack of symptoms or is likely to develop in the next few years.
A coronary calcium scan is simple and easy for the patient, who lies quietly in the scanner machine. There is no injection. The test involves two breath holds and takes only about five minutes. To measure how much calcium has accumulated in the coronary arteries, we use a state-of-the-art 64-slice dual-source CT scanner which is many times faster than a conventional CT scanner.
- Before, during and after a coronary calcium scan
- Why choose the S. Mark Taper Foundation Imaging Center for a CT study?
- The SHAPE Program—dedicated to heart attack prevention
Technetium Pyrophosphate Scan
This scan uses the radioactive isotope Tc-99m pyrophosphate to evaluate whether an unusual type of abnormal heart muscle function (cardiomyopathy) is present. An intravenous injection of pyrophosphate is made at rest, followed about an hour later by a set of images taken while you lie down under a camera.
These images are recorded on a computer for analysis.
The images take about 15 minutes. The entire procedure, from injection to end of imaging, takes about two hours.
In this common type of scan, the radioactive isotope thallium is injected into your vein at rest and at the end of an exercise or pharmacologic stress test. Images are taken after each injection that show how the blood is flowing through your the arteries in your heart. If the arteries have blockages, there is not enough blood flowing through them during stress, resulting in an abnormality on the scan.
This test can also identify regions of damage or scarring of the heart muscle due to previous heart attack. scarring of the heart muscle due to blocked coronary arteries or a previous heart attack.
The S. Mark Taper Foundation Imaging Center has more information about thallium scans, including how to prepare and what to expect.
Like the thallium scan, the sestamibi or tetrofosmin scan shows how well supplied with blood and your heart is. Sestamibi (Cardiolite) and tetrofosmin (Myoview) refer to the type of radioactive isotope (Tc-99m sestamibi or Tc-99m-tetrofosmin) used in this test to make the flow of blood visible. Thallium, sestamibi and tetrofosmin stress tests are more accurate and informative than a standard exercise stress test.
The S. Mark Taper Foundation Imaging Center has more information about the sestambi scan, what to expect and how to prepare.
Wall Motion Tests
This test generates a moving picture of your beating heart and allows your doctor to see how well your heart is pumping. As with other diagnostic tests, you will be connected to an electrocardiograph monitor so that your heart can be watched throughout the procedure.
A small needle will be put into your vein. You will then receive two injections.
The first sticks to your red blood cells for a short time. The second, given about 20 minutes later, is a radioactive substance. Without the first injection, the radioactive substance would not attach to the red blood cells, and it would not be possible to track the flow of blood through your heart's chambers.
After the second injection, you will lie on a special table under a camera for about 15 minutes, during which time images of your heart are obtained. Doctors will use these images to measure the pumping function of the heart (ejection fraction—the fraction of blood pumped out of the heart during each beat).
Depending on the type of wall motion study, additional briefer images in different positions may also be obtained.