Assessment of Pericarditis – Advanced Assessment

00:00 So, the next specific cardiac disease that we should talk about is the assessment of pericardial disease.

00:06 Some patients with simply having pericarditis whether it's viral or potentially in the setting of lupus, or even sarcoid, and various other etiologies, particularly with viral pericarditis, they're going to have pain in their chest.

00:20 And as I alluded to in the very beginning of this talk, this is a person who may look like they're in distress, and they may feel more comfortable sitting upright.

00:27 So a patient with pericarditis typically is sitting upright, leaning forward, because that takes some of the stress off pericardial sac.

00:35 And contrast, when they lie flat, they're more uncomfortable and don't like to be in that position.

00:41 So the cardinal features on physical exam that we're going to be looking for, for pericarditis, and in particular, severe pericarditis with a pericardial effusion and even tamponade are these features.

00:51 Number one, if there's a lot of blood or fluid, a serous fluid in the pericardium around the heart, when I attempt to listen to the heart, it's going to be muffled.

01:01 I'm not going to be able to hear the heart valves crisply the way that it normally would.

01:06 So we would describe in our physical exam that the patient has muffled or diminished heart sounds.

01:13 I may try and make those heart sounds a bit louder by having the patient lean forward to really try and maximally bring about the heart sounds if there otherwise are diminished.

01:25 In addition, while I'm doing that, I may find that the pericardial sac, the visceral and parietal pleura, the visceral and parietal pericardium, are scratching against one another.

01:34 And that's called a rub. A friction rub.

01:37 When people have pericarditis all that inflammation is causing those two materials, those two membranes to rub one against one another.

01:45 And the friction rub of pericarditis is notoriously evanescent.

01:49 It can come and go from one minute to the next.

01:53 But you would hear it down here at the left lower sternal border.

01:56 It's relatively high in pitch, and it sounds like sandpaper, two pieces of sandpaper being rubbed over one another.

02:03 The next thing is what's called Beck's triad.

02:06 And we've already actually talked about one feature of Beck's triad.

02:09 When somebody has pericardial and a pericardial effusion with tamponade, the first thing you'll have as part of Beck's triad is diminished heart sounds.

02:20 You just can't hear the heart as well.

02:22 The second thing you'll have is something called Kussmaul's sign, which is part of Beck's triad.

02:26 And it's basically that, when I take a look at his neck veins again, tilt your head to the left again for me, Shawn.

02:32 Because in tamponade when blood goes to the right side of the heart, during inhalation, when you inspire, that increased blood doesn't have any room, the right atrium doesn't have any room to balloon out at all, because the pericardium is compressing all four chambers of the heart.

02:51 So when the blood goes into the right atrium, rather than the right atrium being able to expand and accommodate that increased blood during inspiration, what happens instead is the interventricular septum and the interatrial septum push into the left side of the heart.

03:07 It's like the right side of the heart is decided that it should take prominence, it's taking an extra volume of blood, and it's pushing the left side of the heart away.

03:16 As you can imagine, if you're pushing the left side of the heart away, that means that there's less blood going into the left ventricle and the left atrium.

03:24 And so once cardiac output goes down, just during inspiration.

03:29 So, there's this to and fro between the respiratory cycle where during exhalation there's a relatively normal systolic blood pressure.

03:39 But during inhalation in inspiration, the right side of the heart crowds out the left ventricular outflow tract and the blood pressure actually can drop a bit.

03:50 So Beck's tried is going to include: muffled heart sounds, hypotension, and because the right side of the heart is accommodating all this extra blood has no room for it to go, we're going to see those jugular veins going up during inhalation.

04:06 Remember, I said before that usually, when you're breathing in the negative intrathoracic pressure is drawing blood towards the heart.

04:14 So you're jugular vein pressure goes down.

04:17 But with a large pericardial effusion there's no room for all that extra blood in the heart because the pericardium is crowding all four chambers, so when that extra blood return goes to the heart, it has nowhere to go.

04:29 So it ends up leading to elevated neck veins during inhalation.

04:34 And that's called Kussmaul's sign, and that's part of Beck's triad.

04:38 All three of those features would support the diagnosis of a pericardial effusion.

04:43 But the number one most important physical exam finding that we can do to diagnose a pericardial effusion with tamponade is pulsus paradoxus.

04:53 And pulses paradoxes, the physiology goes back to what we were just talking about where if there's all this blood going back to the right side of the heart, it's going to crowd out the left side of the heart and compromise the left ventricular outflow tract.

05:07 What happens? The paradox, the reason that the term pulses paradoxus came about was that when Kussmaul, was actually Dr. Kussmaul, back in the 1800s, was listening to the heart.

05:18 And he could hear the mitral and tricuspid valve, the opening and closing.

05:24 He knew that that was systole. He could hear the heart here.

05:27 He can even palpate it, by feeling left ventricular contraction at the point of maximal impulse.

05:31 But out here in the radial artery, he was not feeling the pulse.

05:36 And that's because during inspiration, during inhalation, while the heart was pumping, the cardiac output was so compromised, he could not feel this systolic pressure all the way out here and the radial artery.

05:48 And so that was the paradox was hearing sounds here, but not being able to feel it here.

05:53 That's in somebody with severe tamponade.

05:56 And we're going to do this test called pulsus paradoxus, to try and detect more subtle manifestations or a more subtle presentation of tamponade by looking at the systolic pressure as it vacillates during the respiratory cycle.