A Cardiac CT scan uses advanced CT technology along with intravenous radio-opaque dye (contrast) to obtain high resolution 3-dimensional images of the heart. Small electrode patches are placed on the patient’s chest which allows continuous ECG monitoring during the test.
This test is performed with the patient going into a metal dome, with your arms raised over your head. The patient will be required to lie still and hold their breath for 10 seconds to allow the pictures to be taken. At the same time,the dye is injected via a fine tube (cannula) placed in a vein in the back of your hand. Under certain conditions, a drug may be needed to slow your heart rate down for the test. The table that the patient will be resting on will automatically move into place within a donut-shaped scanner for imaging.
Within the scanner, X-ray tube will emit X-rays and circle the body for 5-8 seconds. The X-rays passes through the body and are picked up by detectors within the scanner, which are then used to generate real time images of the heart muscle, chambers, valves and coronary arteries. The radiation dose of the CT scan is equivalent to a coronary angiogram but is less invasive, with potentially less risk and less recovery time. Narrowings or blockages and the presence of calcium within the arteries can be detected and if significant may support the need for an invasive angiogram.
The procedure takes about 30 minutes and is performed as an outpatient procedure by a technologist with the result reviewed by the cardiologist. Normal activities and diet can generally be resumed immediately after the test.