Hello, my name is Phil Pereira and I'm the Emergency Ultrasound Coordinator at the New York Presbyterian Hospital in New York City and welcome to SoundBytes Cases. In this module we'll continue our journey through the cardiac echocardiography examinations looking at the four standard views. In this module we're specifically going to focus on probe position B as shown in the pictorial here, the subxiphoid view of the heart. Hopefully you've joined me prior for the parasternal views as shown in probe position A and an upcoming module on the apical view as shown in probe position C. The subxiphoid view of the heart is an excellent way of imaging the patient's heart and getting a lot of information directly at the bedside.
Now let's learn how to perform the subxiphoid view of the heart. As shown in the pictorial to the right, the probe is coming from an abdominal position placed just inferior to the xiphoid tip of the sternum. It's important to lay the probe flat and push down and under the sternum, aiming towards the patient's left shoulder.
Now the marker dot on the probe should be over towards the patient's right side, with a caveat that the ultrasound screen indicator dot is over towards the left of the screen. Now it's very important to put your hands on top of the probe and really push down and up to get the good imaging plane underneath the sternum to make the angle to get a good view of the heart from this plane. Let's now take a look at the image that you'll obtain from the subxiphoid view of the heart.
Here's a pictorial to the left and an ultrasound image to the right. The first chamber that we'll encounter directly below the liver, which is our acoustic window in this case, onto the heart, will be the right ventricle. Immediately posterior to the right ventricle will be seen the left ventricle.
And as shown in this pictorial, notice that it has more muscular and hypertrophic walls. From the subxiphoid plane, we'll also be able to image the right atrium to the left of the right ventricle and the left atrium just to the left of the left ventricle. We can also appreciate the white line that is the pericardium circumferentially surrounding the heart.
Now that we know where the chambers are, let's take a look at a video clip of a normal heart from the subxiphoid plane. As we remember, the liver is our acoustic window onto the heart from this plane, and so the liver will be seen anteriorly just to the top of the screen. Just below the liver, we appreciate here the right ventricle. And notice here, just to the left of the right ventricle, we can appreciate the right atrium. Notice the tricuspid valve flipping up and down in between the right atrium and the right ventricle.
Now, let's look posterior to the right ventricle, and we appreciate the left ventricle. Notice again it's more muscular and hypertrophic walls. Just to the left of the left ventricle, we appreciate in this case the left atrium, and we also get a glimpse here of the mitral valve flipping up and down in between the left atrium and the left ventricle. Now let's look at that white line, both anteriorly above the right ventricle and posterior below the left ventricle, that is the pericardium.
Note here the absence of any significant pericardial effusions. In that last video clip, we noted good contractility of the left ventricle from diastole to systole. Let's contrast that clip to this one from a patient who presented with shortness of breath and advanced cardiomyopathy. We see the right ventricle just below the liver, anterior to the left ventricle.
And what we see here is a poorly contracting and dilated left ventricle, consistent with a cardiomyopathy heart. However, note the absence of any significant dark or anechoic fluid collections consistent with a pericardial effusion. Here's a patient who presented with renal failure and acute shortness of breath.
We're again looking from the subxiphoid plane, so we see a little strip of the liver anteriorly, the right ventricle just below the liver, and the left ventricle seen posteriorly to the right ventricle. Notice how hypertrophic the walls of the left ventricle are in this patient. We also appreciate a dark fluid collection both anteriorly, just below the liver and above the right ventricle, and posterior below the left ventricle, consistent with a circumferential or large pericardial effusion. If we see a large pericardial effusion on bedside echo, our next move is to look for signs of cardiac tamponade.
Here's a patient who manifests all the signs of cardiac tamponade on bedside echo. Let's look specifically at the right side of the heart. Notice the very large pericardial effusion and note the chaotic movement of the right ventricle as it struggles to open during diastole. The compression of the right ventricle in this patient is consistent with advanced cardiac tamponade.
The right side of the heart is preferentially compressed before the left ventricle due to its lower pressure circuit. In conclusion, I'm glad I could share with you the SoundBytes module going over the subxiphoid view of the cardiac echo examination. This is a very important exam to put into your routine practice in looking at your patient's heart at the bedside, and will tell you if the patient has a pericardial effusion, as well as giving a sense of left ventricular contractility. Also, the subxiphoid view of the heart gives better views of the right side of the heart than the more superior parasternal views of the heart.
So I hope to see you back as SoundBytes continues and as we move on to discuss the other echo exam planes of the heart.