What is a CT coronary angiogram scan?

Transcript

If you have been referred for or considering having a CT coronary angiogram, this video provides you with a detailed overview of the process, the benefits and the risks involved. A CT coronary angiogram is a detailed imaging modality that focuses on the blood vessel supplying your heart. We refer to these as the coronary arteries.

The coronary arteries supply the heart muscle with oxygen-rich blood. A CT coronary angiogram is particularly valuable in individuals who have been experiencing symptoms such as chest pain or breathlessness and in these particular individuals it is critical to rule out blockages in the heart arteries. However, more recently these scans are being used in individuals without any symptoms but in whom we suspect that there is an increased risk of cardiovascular disease.

This includes individuals who have a family history of heart disease, who have diabetes, who smoke, who have other cardiovascular risk factors such as high blood pressure and high cholesterol. There are two distinct phases in having a CT coronary angiogram. The first phase involves no contrast and detects calcified plaques.

These are fatty deposits that have become hardened over time. These calcium deposits serve as a marker of atherosclerosis and provide an individualised calcium score. Your calcium score is highly predictive of your future risk of cardiovascular disease.

We can use your score and compare it to individuals of the same age and gender and rank you using a percentile ranking. For example, a 50th percentile score indicates an average calcium level for your demographic, while a 99th percentile score suggests a significantly elevated risk of a future cardiovascular event. What a calcium score doesn't tell us is if there are any narrowings of the coronary arteries.

To do this, we inject contrast which is the second part of the scan. When we inject contrast, we can see if there are any narrowings of the coronary arteries and critically if there is any soft fatty plaque. Now it's important to know about this as it is the soft fatty plaques which are more prone to rupture and cause heart attacks.

Now let's talk about radiation. This is clearly a concern. However, we can reassure you that we use the latest generation scanners which have a fraction of the radiation exposure compared to the initial scanners we used to use.

For example, our scanners will acquire all the images needed in a single heartbeat. So how much radiation do we expose you to? Well, let's put this in perspective.

The radiation dose emitted by our latest generation CT coronary angiogram scanner is equivalent to the dose you would absorb if you lived in Cornwall for six months.