Cardiac Imaging

Dr Wedderburn-Maxwell & Partners Inc have high performance comprehensive cardiovascular software applications including: coronary vessel analysis, cardiac functional analysis, calcium scoring and peripheral vessel probe. The software includes capabilities for viewing 2D, 3D and 4D cardiac images of the heart.

In the past CT imaging of the heart was almost impossible due to the coronary arteries and other cardiac structures that are moving rapidly during the cardiac cycle. In the last few years CT scanners (Computerised Tomography) has made such great advances that imaging a moving object, like the hear is easy. Our 64-slice scanner can acquire these images in approximately 9 seconds and with the help of the ECG monitoring the images are retrospectively reconstructed. These thin slices can then be used to examine all the coronary arteries as well as produce a movie of your heart beating and 3D images of your heart.

On arrival in the department we will check your heart rate. We will then give you a tablet (beta blocker) that will regulate and slow your heart rate slightly. This improves the image quality and helps ensure a diagnostic study. When the heart rate is stable, the CT examination can begin. An intravenous line will be placed in your arm so we can administer an x-ray dye.

The CT cardiac study will include a calcium score and a CT coronary angiogram.

The calcium score is used to calculate the amount of calcium within the coronary arteries and your risk of coronary artery disease. The amount of coronary calcium has been recognized as a powerful independent predictor of future cardiac events and may be used to guide lifestyle modifications and preventive medical therapies to reduce this risk.

Absence of calcium is considered a "negative" exam. However, since there are certain forms of coronary disease, such as "soft plaque" atherosclerosis, that escape detection during this CT scan, it is important to remember that a negative test indicates a low risk but does not absolutely exclude the possibility of a future cardiac event.

Once the calcium score is complete we will continue onto the CT coronary angiogram which allows us to visualise the inside of the coronary arteries as well as the wall. Up until recently this could only be examined using invasive catheterisation. A contrast media or x-ray dye will be administered in order for us to visualise soft plaques within the coronary artery.