CT coronary angiogram vs invasive angiogram: what is the difference?

Transcript

So when we talk about a CT coronary angiogram and an angiogram or an invasive angiogram, we're actually talking about two tests that do the same thing. They're imaging tests of the coronary arteries, the blood vessels that supply your heart. The key difference is that a CT scan is a non-invasive scan, so there is no risk to you in terms of complications such as heart attack strokes, the need for emergency surgery or death.

A CT scan tells us whether there are narrowings in the heart arteries, but we'll also look at the vessel wall to see if there's any buildup of plaque, be that calcified hardened plaque or non-calcified soft lipid. An invasive angiogram shows you whether there are blockages in the heart arteries, but doesn't show you whether there is any plaque as such. It shows you whether there is a narrowing.

That's the key difference. Now, the advantage of an invasive coronary angiogram is that if we see a blockage, we can actually measure how significant that is clinically, does it cause a reduction in blood supply to the heart muscle, and at the very same sitting, if we establish that using something called a pressure wire study, we can actually unblock that vessel for you with something called coronary angioplasty, and typically that involves deploying a stent, which is a cylindrical metal scaffolding that keeps that narrowing from recurring.