Doctors need to practise for years to get good at performing often very tricky procedures. But rather than make mistakes on real patients, modern technology means it’s now possible to rehearse complicated procedures using simulators first. And it can be very realistic, and very stressful, as Tom Crawford found out when Gareth Wills from Vascular Perspectives got him threading a tube into a pretend coronary artery, one of the blood vessels that can become blocked and cause a heart attack...
Gareth - What we’re going to do in a couple of minutes is insert an 035 wire into the radial artery. It’s called an 035 wire because it’s 35 thousandths of an inch in diameter. The radial artery is in the wrist. What we’ll do is we’ll push this wire, which has got a very soft tip, up the radial artery to the forearm where it joins to the brachial artery in the elbow. Up to the top of the shoulder and across the top of the chest where you have the brachiocephalic artery, and then down the descending aorta, which is where it joins to the heart at the aortic root. From that we then push a catheter, which is essentially just a tube, that joins the outside world to the inside world, push that over the wire all the way round to the heart and then we connect a radiopaque dye to the end at the wrist. Using this radiopaque dye, we can inject that into the heart and look at it under live X ray and see the coronary arteries.
And your wire is in the arm…
Tom - I can see it inside the…
Gareth - This is the forearm here so if you start pushing that forward you’ll see it travel up the elbow. It goes very quickly…
Tom - It does wow.
Gareth - You’re up to the shoulder now.
Tom - There’s a huge difference there between how hard I was pushing it initially. Oh God, I can see the heart on the screen.
Gareth - It’s beating which is a good sign.
Tom - So it’s a case of using this wire and the catheter (the tube) to put this dye on the heart so that then when you do an X ray you can see the heart. Because, of course, when you do an X ray normally you just see bones - is that correct?
Gareth - Exactly. X ray only picks up hard tissues and not soft tissues. You’re exactly right, you can see bones, you can see a faint outline of muscle, but what we want to see is the vessels that supply the blood to the muscle. So we use the blood vessels as a conduit to inject the radiopaque dye. The patients who’ll be getting this procedure done generally have angina, which is chest pain at rest or after exertion. If they have chest pain it’s usually because they have a narrowing in one of these coronary arteries, and the coronary artery feeds the blood to the cardiac muscle. If you have chest pain it’s because your heart isn’t getting enough blood to the cardiac muscle. So what we do is we put this catheter in, inject the dye and look for the narrowing.
Now what you need to do is manipulate the catheter to get into this little bubble here.
Tom - It’s like a game. Can I put the syringe down?
Gareth - You can. You can relax as well.
Tom - It’s intense.
Gareth - As you say, in the past, doctors would train on live patients. They would learn at the right hand side of an experienced consultant, generally just by watching, and then they would go through the whole see one, do one, teach one. But nowadays you’ve got systems like the mentes where there is zero risk to a patient, and this is live, or real patient data, so learning with a zero risk strategy seems to make much more sense.
The problem is doctors generally don’t have a lot of time to do simulation on top of everything else that they do so that’s where we try and help out at conferences like BCS where we can offer training like this in an enclosed environment where the doctors have time to do this. But generally, we feel that simulation is obviously the safest, lowest risk way of learning the way to do a proper coronary angiography.
Tom - I know you were telling me to chill out but it feel real, which is good, right?
Gareth - Yeah.
Tom - Because you’re trying to recreate the real world environment that the cardiologist could be in.
Gareth - It’s called immersive simulation. As close to real life as possible.
Tom - I know that was…. I’m terrified.