Mastering the parasternal short-axis (PSAX) echo view of the aortic valve

In this video from our Echocardiography Essentials course, you will learn how to display an optimized PSAX AV image on transthoracic echo and how to recognize the structures, assess them, and decide if they are normal.

After completing this course, you’ll be able to perform a basic transthoracic echo (TTE) exam without the help of a more senior colleague. Using practical demos, we’ll teach you echo anatomy and show you how to operate the machine, obtain the standard TTE views, differentiate normal from abnormal, and confidently assess and report anything you find!

[00:00:00] This shows where the parasternal short-axis view, at the level of the aortic valve, cuts through the heart. This is our probe and you can see the ultrasound moving into the heart. The first structure it encounters is the right ventricular outflow tract. Behind it will be the aortic valve and the left atrium. So, now we're going to scan in the parasternal short-axis views. So, whereas my notch was pointing towards my patient's right shoulder on my long-axis views, I'm now going to

[00:00:30] rotate my probe, around like this and so that it's going to be pointing at the left shoulder. So, what I usually do is I usually start back in the parasternal long-axis view. So, I'm in the same position as I was, fourth intercostal space, left-sided sternum. And then I rotate around, watching the picture on the screen. So, I'm rotating slowly around about 90 degrees so that I'm pointing now at the left shoulder. So, that's a nice view

[00:01:00] through the left ventricle in the short-axis view but I wanted to start off with my aortic view. My aortic parasternal short-axis view. So, I'm going to angle up very, very slowly, tiny movements. I'm going anteriorly and I'm going up, up, up, keep going, keep going, up, up, tiny movements so I bring in, there you can see the aortic valve is coming in there beautifully. So, what we've got here, we've got the circle. The circle here

[00:01:30] is the aortic root and you can see the cusps of the aortic valve, in the middle there. And then this is a diagram of the parasternal short-axis view at the aortic valve level. And as we know, our probe is up here. So, our first structure we see is the right ventricular outflow tract. Then we see the aortic valve behind it and a closed, normal aortic valve, looks like this. So, it's like the inverted Mercedes sign or a Y. This cusp is the right coronary cusp and we know that because we know the right structures are the ones

[00:02:00] we're insonating first, in this view. We've actually got the right coronary artery coming off, here. This is the left coronary cusp and this is on the left, as the patient lies on the bed. And you can see the left coronary coming off, here. And then the other cusp is the non-coronary cusp. Behind it, we have the left atrium and here we have the right atrium. And so this structure, here between them, is the interatrial septum. So, hold this view in your head and we'll see it in a real patient. So, in the parasternal short-axis view, at the level of the aortic valve,

[00:02:30] we're looking to see the aortic valve within the circle. If it goes a bit oval, it means we've gone off of axis. So, to look at the structure and the function of the valve in this view, I will optimize my circle and if I'm not sure that I'm on it properly, I will go back to my parasternal long-axis view and start again.

[00:03:00] That's better. So, I can see thin cusps there opening well. I can see them closing in the position of the Mercedes sign. Here we are. And what I'll do is put some color here, just to see whether there's any aortic regurgitation. I didn't see any in the other view but I can't see any here either. The other valves I see in this view are the tricuspid valve, over here and the pulmonary valve,

[00:03:30] over here. So, there's a lot going on in this view so we're going to have to spend quite a lot of time looking at it properly. So, this is a nice view for looking for tricuspid regurgitation. We're quite well-aligned, up here, for Doppler flow. So, I'm looking at forward flow through the valve, is red, up towards the screen and then I can't really see any TR. There may be a tiny flip but nothing I can possibly try and measure. That all looks normal. So now I'll go over and have a look at the pulmonary valve and as before we see

[00:04:00] the little, tiny jet of pulmonary regurgitation, up there in the valve. And then nice laminar flow into the main pulmonary artery. And then the bifurcation, we can just about see, there. That's just quite nice, we can see the bifurcation of the two branches. So, more to look at in this view. There's the interatrial septum. So, that's this structure, here. So, we got the left atrium, here

[00:04:30] and the right atrium, there. So, we could look at the septum and see whether it's thin, whether it's particularly mobile. Pictures aren't' perfect here but we could put color and we could check whether there's a PFO or an ASD there. The structure off at the top is the right ventricular outflow tract. So, we can look at the wall there but it may not be particularly useful. And the other structure we may see in this view is SVC, coming into the right

[00:05:00] atrium and we'll notice that as a surge of color, you see that red color, there, coming into the atrium. That's SVC flow. It's important not to confuse that with ASD flow. So, that's SVC into the right atrium.