CARDIAC IMAGING
Cardiac imaging covers a range of services which all capture images of your heart and heart valves.
Your doctor may refer you for cardiac imaging for one or more of the following reasons:
- Investigate chest pain
- Screen heart disease or a heart condition
- To examine the function and health of your heart and heart valves
- To assess the effects of a heart attack or stroke
Your referring doctor will discuss with you which scan is most appropriate for your condition.
CT Calcium Score
The coronary artery calcium score (also known as CT calcium score) is a measurement of the amount of calcium in the walls of the arteries that supply your heart muscle, using Computed Tomography (CT) technology.
Calcium scoring does not measure how narrow the arteries are, rather it is a way of looking at the overall amount of cardiac plaque present, which can help predict your risk of a future cardiac event.
Your doctor will use the calcium score to decide whether you are at low, normal or high risk of a future heart attack and give you guidance on how to reduce your risk.
Please continue your regular medication as normal. However please inform us if you are taking any diabetic medication, have kidney disease or have had a previous reaction to imaging contrast.
You will need to avoid any caffeine and smoking 24 hours prior to exam and cease exercise on the day of the examination. You will be given a beta-blocker drug upon presentation to our practice, to slow the heart and keep it at a steady beat, prior to imaging.
You may be asked to change into a gown and/or remove jewellery.
ECG leads will be placed onto the chest to allow monitoring of the heart rate during the examination.
You will lie on a table which is slowly moved into the doughnut shaped CT unit and scanning will take place at a time where optimal visualisation of the heart can be achieved. Detectors capture the x-rays passing through the examined area for the computer to interpret into images.
CT Coronary Angiogram
CT Coronary Angiogram (CTCA) is the most sensitive non-invasive test for detecting Coronary Artery Disease, using multi-slice Computed Tomography (CT) technology to examine the blood vessels that supply the heart muscle.
This examination provides valuable information for your doctor, detecting if plaque has developed in the coronary arteries that may result in blockages, potentially causing symptoms or increasing your risk of heart attack. It is especially useful in determining whether the coronary arteries are the cause of symptoms such as current chest discomfort or shortness of breath.
You are required to fast for 2 hours prior to your examination. Please do not have anything to eat, drink, smoke or chew during the fasting period.
Please continue your regular medication as normal. However please inform us if you are taking any diabetic medication, have kidney disease or have had a previous reaction to imaging contrast.
You will need to avoid any caffeine and smoking 24 hours prior to exam and cease exercise on the day of the examination. You will be given a beta-blocker drug upon presentation to our practice, to slow the heart and keep it at a steady beat, prior to imaging.
You will be required to remove all clothing from above the waist and asked to change into a gown.
ECG leads will be placed onto the chest to allow monitoring of the heart rate during the examination. A small plastic IV catheter is placed into a vein of your arm. A syringe filled with contrast is placed in a mechanical pressure injector and attached to the catheter. A spray of GTN (angina medication) will be delivered under the tongue to dilate the heart arteries.
You will lie on a table which is slowly moved into the doughnut shaped CT unit. Housed within the CT is an x-ray tube which rotates around you. Detectors capture the x-rays passing through the examined area for the computer to interpret into images. You may be asked to hold your breath for a few seconds during the scan.
The injection process will then start. Most people experience a temporary warming sensation when the contrast is administered. This dissipates quickly. Scanning takes place at a time where the optimal visualisation of the arteries can be achieved.
Myocardial Perfusion Scan
A Myocardial Perfusion scan evaluates coronary artery disease by assessing the blood flow to the heart muscle both at rest and at stress. It identifies major blockages to the blood supply of the heart and assesses the extent of damage to your heart caused by heart disease.
You are not required to fast for this procedure, however a light meal 2-3 hours prior to your examination is recommended. No caffeine for 24 hours prior to your appointment. This includes coffee, tea, green tea, chocolate, cola soft drink. Please advise us if you are a diabetic.
- Bring a list of your medications.
- Wear comfortable clothing and shoes.
- Bring a jumper or cardigan.
Feel free to bring along a book, iPad, headphones or similar as there are periods of waiting.
Upon arrival, an IV cannula will be inserted into your arm. This will remain in place for the entire duration of the examination.
Our Nuclear Medicine Technologist will administer an injection containing a slightly radioactive tracer, which is absorbed by your heart muscle. There are no side effects from this tracer and it contains only a small amount of radiation.
You will then be asked to sit and wait for 30-40 minutes while the tracer travels to the heart. After this time, imaging of your heart will commence for 20 minutes. For the next stage of examination, your heart rate is required to be raised so we can image your heart after it has been working harder than normal. To do this, we will ask you to walk on a treadmill. If you are unable to walk on the treadmill, we will issue a medicine that simulates you doing this exercise. Again, you will be asked to wait for 30-40 minutes before another 20 minutes of imaging commences.
