Event 20: Anatomy of Chest Pain with Darren Salmi

00:00 Hello everyone. Welcome to our webinar series on the anatomy of chest pain with Doctor Salmi. So we're going to be a very exciting day. We're going to kind of look into a little bit of anatomy.

00:10 What is in your chest? What can make it hurt? Go over some differentials of what could be causing the different types of chest pain.

00:17 It's going to be very much like overview, but like interesting.

00:20 I've looked through the slides and they're pretty fascinating, so I'm excited if we have before we dive into it, we do have a couple questions.

00:27 We just wanted to get to know all of you who's out there.

00:30 If you want to let us know where you live, um, let us know. Hi, Deidra from Kalamazoo, Michigan.

00:35 I used to live right by there.

00:36 Awesome. We have a few questions just to kind of get to know you.

00:40 And you can get to know this entire platform.

00:42 Um, we have our poll, uh, which is kind of like, what describes you best? Where are you in your healthcare education journey? Um, we you're going to be able to actually click buttons on the screen.

00:54 This is mostly just for fun, uh, and to keep you from getting super bored.

00:58 So go ahead. You can click one of those.

01:00 Let us know. Are you like a pre pre pre-nursing student pre med school.

01:04 Are you an MPA med school nursing.

01:07 Uh this is our first event where we're doing it for everyone. Because really this is a topic that affects everybody.

01:12 Uh, so we're excited about that too.

01:14 Um, you can use the chat here.

01:16 If you have questions, you can leave them in the chat.

01:18 This is a live event. We will tag some of them to answer.

01:22 We're going to have a whole Q&A section at the end.

01:25 And so if there's a question that's super relevant to what we're talking about, we'll be able to put it on the screen.

01:31 Um, and Doctor Sam can answer it then.

01:34 If not, we'll save them for the end during a little Q&A section.

01:37 And this is going to run for about like 45 to 50 minutes, maybe a little bit later with like the Q&A section, uh, going forward from there.

01:46 And then our second poll is going to be have you what's your familiarity with Lecturio.

01:51 So is this something that you have used before or is this something that you have like the free version.

01:58 Do you have the premium version? Do you like it? What can we do better? Er, all of your grievances in the chat now.

02:04 Um, this is your free your platform to do so and I will see what I can do about it.

02:09 Um, I just kind of gives us an idea of who's watching.

02:12 Do you know us, or is this our first time meeting? And if so, welcome. And. Hello. Uh, and you can let us know if you've ever been to one of these events. And you guys I see coming in from. Absolutely, like, all over. We have someone from the Netherlands, Nigeria, Bolivia. This is so cool.

02:27 India. Um, the UK. So this is super duper cool to see all of you coming in from all over. Um, thanks for letting us know where you are from.

02:37 And now I'm going to bring in, uh, Doctor Salmi.

02:41 He is. If you guys have Lecturio and you've seen a lot of our anatomy lectures, he does a ton of them for both medical and nursing.

02:48 He's a clinical assistant professor of pathology and surgery at Stanford University, and he has put together this awesome presentation for us today.

02:54 So I'm going to hand it over to him and I'll just be in the background answering your guys questions if you have any.

03:01 Thanks for being here. Fantastic.

03:03 Thanks for having me. I'm very excited to be here in front of such a large group of people from all over. I was checking that Chat two and Poland, Nigeria, Guatemala everywhere.

03:15 Uh, and a nice mix too.

03:16 It looks like, um, yeah, about like half for med students, half our non med students.

03:21 We got a nice, uh, cohort of nursing students.

03:24 And, you know, as Nurse Liz mentioned, I do a little bit of both.

03:28 So you might see me in the nursing anatomy.

03:30 You might see in the med student anatomy. And the slides we're going to look at today are kind of pulled from those more in depth anatomy lectures.

03:39 But what we're going to do today, because we only have a very brief amount of time, is we're going to have a focused sort of preview, maybe slash review for some of you who've already done some anatomy, specifically regarding the anatomy that's related to chest pain And in doing so we're going to talk about, you know, the anatomic structures within and around the chest. And when we say chest pain you probably jump to cardiac pain which makes sense right. There's a lot of reasons why you think that. A lot of it has to do with just how serious cardiac causes of chest pain can be.

04:13 But we're going to cover cardiac but also non cardiac anatomy slash causes of chest pain.

04:18 And in doing so we're going to sort of practice going through a differential diagnosis through a couple case studies.

04:24 Many case studies more like patient presentations and kind of make the connection that especially if you're early on or have yet to begin your training and healthcare fields, really understand like how the anatomy connects directly into these clinical presentations. Right? And so that's the point of learning anatomy is because we apply it all the time in our practice, whether that's nursing, medical or other healthcare fields, PA and PE.

04:52 A&p. You know, it's foundational.

04:55 You know, it's the body.

04:56 We're treating bodies. And we got to know what parts are in the body in order to know where things are going wrong and how to fix them.

05:04 So we're going to start with the chest.

05:07 What does that even mean.

05:09 Right. So that can mean a lot of things.

05:12 Especially this is a patient who doesn't have the kind of training y'all are going to have when it comes to describing their pain.

05:19 Right. So when they say chest pain, just kind of a silly example, but not really. You might have a friend or somebody who just does 100 push ups in a row and says, ah, I'm having like chest pain.

05:32 And that's not really what we think of.

05:34 You might think, well, you really have soreness in your pec major.

05:37 Some anatomy for you, right.

05:38 More upper limb anatomy.

05:40 And that's, you know, kind of the vagueness when we say chest pain.

05:45 Like that's not really what you all are probably thinking of when we say chest pain.

05:51 But to someone who doesn't have the anatomic knowledge that you all have or soon will have, that could be a perfectly logical, logical way of explaining it.

06:00 I have pain in the region between my neck and my abdomen, right? And that's pretty vague.

06:08 So chest pain itself can mean a lot of things, right? So there's a lot of causes for chest pain.

06:15 Do we mean like the chest wall, the physical structures around the chest cavity, like things we can touch, or do we really mean the stuff inside the chest cavity where we have a couple of really vital organs, like the lungs and the heart, of course.

06:31 So in going through chest anatomy, however, we kind of think of that very broadly. It's going to serve as the basis for how we formulate our differential diagnosis or the things that we're going to be thinking about when someone comes in with this chief complaint of chest pain.

06:50 Let's start with that chest wall.

06:52 The outside part of our chest cavity.

06:55 The part that you probably don't jump to right away when you think of the term chest pain. Well, we have this, like really strong support structure around our chest cavity. Kind of loosely we call the rib cage.

07:10 Now the rib cage isn't entirely ribs.

07:13 Of course if we look posteriorly, we have these very important bones back there making up our vertebral column to which the ribs attach posteriorly.

07:23 And then anteriorly we can see there's this midline set of bones here that we call the sternum. And the superior most part we call the manubrium.

07:35 This large part in the middle, the middle we call the body.

07:39 And there's a pointy thing at the bottom that we call the xiphoid process.

07:45 And yeah, you know, you can memorize these things if you have a really great memory, I don't. So I need tricks to help me know this rather than memorize it.

07:54 And what do I mean? I kind of learn what these words mean.

07:58 So these words are kind of helpful once you know what they mean.

08:04 For example, xiphoid means sword like.

08:07 Well, that kind of makes sense to me because we just described it as this pointy thing at the bottom of the sternum.

08:12 So xiphoid or sword like, oh, that's that's pretty easy to remember.

08:16 What the pointy thing at the bottom of the sternum is going to be called. Similarly, manubrium means handle.

08:22 And now it really is making sense because it kind of looks like it's the handle of a sword that's pointing upside down.

08:30 So that's the first part we're going to talk about. We have that sternum part in the midline. And on either side of the sternum we have some cartilage we call costal cartilage.

08:43 So costal is another good time to dive into those words.

08:47 Costal refers to ribs.

08:49 So when you see costal kind of automatically replace in your mind costal with rib.

08:55 So this is rib related cartilage.

09:00 And at the inferior margin here we see that it forms this this rim here or arch of cartilage. It's called the costal margin.

09:11 And that's going to be sort of our inferior edge at least from the anterior point of view of our chest cavity. We'll tilt a little bit to sort of a lateral view to see the ribs themselves a little bit better.

09:26 And we actually see that only the first seven ribs kind of fit this model of what we consider a true rib. So we say the first seven ribs here are true ribs because they start at the vertebra, go all the way around the chest cavity, have a costal cartilage they attach to that attaches to the sternum.

09:48 We can see. All right that's the same for 234567.

09:53 But by the time we get to rib eight we see something's a little different.

09:58 So these ribs we call false ribs because as you can see here with rib eight it's costal cartilage has to attach to the costal cartilage of rib seven above it similar for the ones below it. So rib nine is going to attach to a costal cartilage that attaches to the costal cartilage. Rib eight, which in turn attaches to the costal cartilage of rib seven.

10:24 So those ribs that I just described only indirectly attach to the sternum.

10:31 And then in particular these last two way down here, ribs 11 and 12, we can see don't attach to costal cartilage and therefore the sternum at all. So those are Our floating ribs, a subset of the false ribs.

10:46 And then finally, we know that we're going to seal off this thoracic cavity or chest cavity from the abdominal cavity by the presence of our diaphragm.

10:57 And I can't help throwing in a little bit of embryology because I also teach embryology.

11:02 And I think if you really, really want to understand anatomy, you kind of have to know how it formed in the first place.

11:09 And we actually start out early in development with one single body cavity.

11:15 And it's the diaphragm that comes along and separates it into a separate thoracic and abdominal cavity. Or in other words, a separate pleural and peritoneal cavity.

11:26 And I say that because we're going to talk about the pleural lining of the chest cavity, which is pretty much the exact same thing as the peritoneal lining of the abdominal cavity. All right. So that's kind of the boundaries of like what's holding the chest cavity inside. So what's what's inside? Well let's talk about that pleura thing.

11:47 So if we imagine a cross section here where we have an example of our lungs, we see that the lungs on their surface have this thing called visceral pleura.

12:02 And so this is something called a cirrus membrane.

12:05 Cirrus means watery. So it's something that's producing a watery fluid.

12:09 And it's visceral because it's on the viscera.

12:13 It's on the surface of an organ.

12:15 So when you see visceral viscera it usually means like related to an organ.

12:21 And this has a very thin lining of cells called mesothelial cells.

12:26 I also can't help but throw in a little histology because I also teach that.

12:30 And this lining goes all around the surface of the lung.

12:34 And you can see here it doubles back and goes from green to blue, and it does so at this little indentation of the lung called the hilum, where structures enter and exit things like the bronchus, pulmonary artery, pulmonary veins, etc..

12:54 And as that serous membrane comes off and attaches to the surrounding chest cavity we have the parietal pleura.

13:03 And so we have that colored in blue.

13:07 Parietal means like like wall.

13:10 So this is the wall of the chest cavity as opposed to the surface of the organ.

13:17 And that parietal versus visceral explanation.

13:20 Adjective usage is the same when you get down into the abdomen.

13:24 You talk about parietal peritoneum and visceral peritoneum.

13:28 Parietal peritoneum would be lining the wall of the abdominal cavity, and visceral pleura would be something like lining the outside surface of your small intestine, for example.

13:42 And between these two layers, you have a little tiny space with typically just a little bit of fluid.

13:49 And why would you have that? Well, even though this is a static image, we know that the lungs don't just sit there.

13:56 Right. They're not, you know, the liver.

13:58 That's just kind of one size all the time.

14:01 The lungs are inflating and contracting, so they're always changing shape.

14:06 So they're always moving, right.

14:08 Well they're hopefully always moving because that's how we breathe, right. So that pleural fluid that exists in the pleural cavity decreases that friction between the visceral and parietal layers of our pleura.

14:23 What about the lungs themselves. Right. So let's sort of do a little x ray vision through the lungs to see what's going on inside, at least to the point we can still see grossly or with the naked eye, a lot of the real important structures like alveoli are going to be microscopic.

14:39 So here we see the trachea coming down and splitting into left and right main bronchus.

14:47 And they're going in and delivering air air in and air out right.

14:52 So the bronchi are going to branch into many, many, many tiny branches eventually down to little, little tiny alveoli. And alongside them we're going to see branches of the pulmonary artery. And those two things branch together because that's essentially what an alveolus is, a tiny layer of epithelium and a tiny, tiny capillary in order for gas exchange to take place. And notice these are pulmonary arteries.

15:22 And I'm pointing to the blue things.

15:24 And you probably typically think of arteries as being drawn red and veins as blue.

15:30 Well that's true outside of the lungs but we don't really define arteries and veins by whether they carry. Oxygenated blood or deoxygenated blood.

15:39 We mean, if it's going away from the heart or coming towards the heart.

15:43 And in the case of the lungs.

15:45 Pulmonary arteries are going away from the heart in order to get oxygenated in the lungs. That's why the pulmonary arteries are labeled in blue.

15:54 And the pulmonary veins, which have now just been.

15:57 Oxygenated are coming back to the heart, are colored red.

16:02 So it's a little different than it is pretty much everywhere else in the body.

16:07 And again, all of these structures enter and exit at this little indentation on the medial aspect of the lungs called the hilum.

16:18 Next we're going to look at the digestive system like why would the gastrointestinal system. We're talking about chest pain. And when you think digestion and gastrointestinal system your mind probably jumps straight to the abdomen.

16:33 And granted, that's where the majority of the digestive system or the gastrointestinal system is going to be located.

16:40 But I think it's good to remember that it actually begins up in the head and neck anatomy area with the mouth or oral cavity, which leads into the pharynx, before finally becoming this long, skinny tube.

16:55 The esophagus, which is really the thoracic part of the gastrointestinal or digestive system because now it's the job of the esophagus to bridge the gap from mouth and pharynx all the way down past the diaphragm and into the abdomen so it can deliver that food bolus, for example, into the stomach.

17:17 Here we see a little lateral view of the esophagus and how it's really traversing the chest cavity here. If we zoom in at the proximal region we see just how closely our Are respiratory structures are related to our digestive structures.

17:34 Here we see the larynx giving way to the trachea, which will eventually bifurcate or split into two bronchi to supply the lungs and just around that same area.

17:46 In fact, even just going posterior to the larynx, we have the pharynx, which will finally terminate around the level the larynx ends and become the esophagus.

17:58 You can see the esophagus and trachea sort of go down together all the way until the trachea splits off into bronchi.

18:07 And again, I just can't resist pointing this out.

18:09 But if you haven't learned this yet, you should go check out some cool embryology about how the trachea and bronchi and lungs develop.

18:17 They actually develop off of the primitive precursor of the esophagus.

18:22 So it's no coincidence these two tubes are sitting side by side like this.

18:27 Turns out the trachea developed off of the esophagus.

18:32 But if you're not eating anything, the pharynx and the esophagus are usually cut off from each other by a closed upper esophageal sphincter.

18:43 Right. Kind of makes sense, you know? Most of the time, the esophagus should be empty.

18:48 Similarly, if we go distally past the diaphragm, which has been faded out so we can look down into the abdomen to see the stomach, we're going to have a lower esophageal sphincter at that junction between esophagus and stomach, also called the gastroesophageal junction or the GI junction.

19:11 Same thing. It will just kind of relax when a food bolus, for example, needs to make its way out of the esophagus and into the stomach.

19:20 All right. And finally we're going to actually talk about the heart.

19:23 You know, again, I would assume when you hear the term chest pain.

19:27 Your mind immediately goes to the heart.

19:30 So we will talk about it.

19:31 But actually, before we even talk about the heart, we have to talk about the sac in which the heart sits inside this portion of the chest we call the mediastinum the middle part of the chest cavity.

19:44 So the heart doesn't just sit around the chest cavity, somewhat exposed, if you will.

19:50 It's in this pericardial sac.

19:54 And here it's been faded out so that you can see the heart underneath it.

20:00 But the pericardium, if we were to zoom in a little bit, has a lot going on. So for example, in this zoomed in view we see the myocardium or the muscle, the working muscle of the heart.

20:14 You know that's what the heart is right. It's a very special type of muscle, very important muscle.

20:19 But still it's mostly muscle.

20:22 So we have the myocardium that's going to end in epicardium.

20:27 Epi means upon is sort of the outermost part, and that epicardium is going to be covered with visceral pericardium.

20:38 Again, visceral means on the surface of an organ, just like visceral pleura was the pleura right on the surface of the lung? The visceral pericardium is the pericardium right on the surface of the heart, not the stuff on the outer sac of the pericardium.

20:58 And we also throw in for good measure.

21:00 We specify serous pericardium.

21:03 Again serous means watery.

21:06 And there's a reason we call it serous because this pericardium makes a little watery substance. Now if we look on the sac that surrounds the heart we see we get the same naming nomenclature.

21:21 We have a parietal layer.

21:23 Again, what would you say? Of the serous pericardium.

21:28 And again serous means watery.

21:29 So in between these two.

21:31 Visceral and parietal layers of serous pericardium.

21:35 We have a small amount.

21:37 Typically of pericardial fluid.

21:41 Same idea as the pleural fluid was in the lungs, right. The heart hopefully, is always beating.

21:51 And so it's not a static organ.

21:53 It's always moving. And this pericardial fluid reduces the friction between these two layers of pericardium.

22:02 And that's why we throw in sometimes that that extra word serous as a reminder that we're talking about these layers here on either side of the fluid.

22:11 But if we were to go to. The outer surface of this parietal pericardium, we would find it's a very, very tough.

22:20 And that would be the fibrous pericardium.

22:22 A lot of collagen fibers, a lot of connective tissue.

22:25 And so that is really more the strong supportive aspect of the pericardium rather than the inner layer that's making this nice little bits of fluid for us.

22:37 We're going to just really, really quickly go through the outer surface of the heart itself after we've taken that pericardial sac off so we could see it.

22:49 And we're going to go kind of like imagining where some deoxygenated blood coming in from some vein in the shoulder, for example, on its way to the heart to then get up to the lungs, then come back to the heart and then go out to systemic circulation throughout the body again.

23:09 So that means we're going to start by looking at the two big veins on the right side of the heart, which are the superior vena cava or SBC and the inferior vena cava or the IVC, and these very large veins are receiving deoxygenated blood, the kind you usually expect in a vein, delivering it into the first chamber of the heart, the right atrium, which we can see a little bit of here.

23:41 Then the right atrium is going to feed into the right ventricle, which in turn is going to pump out into the pulmonary artery to go to the lungs to get oxygenated. Now it's going to go do its thing, break down all the way to the level of an alveolus, get oxygenated, come back via pulmonary veins and into the left atrium.

24:07 But we can't really see it so well here.

24:10 And that's because in an anterior view of the heart, the heart doesn't sort of sit just like very symmetrically.

24:16 It's a little tilted, such that an anterior view shows mostly right sided structures. So we do see a little tiny bit of one pulmonary vein and a little bit of the left atrium there.

24:28 But mostly we see just a little bit of the left ventricle that the left atrium feeds into. And again, that's that's normal.

24:36 Um, we can also see where we make the division, just even from the external surface of the heart between left and right ventricle.

24:45 Now we know. Or maybe we'll learn that if you haven't learned it already, we know that inside there's a wall between these two ventricles that's called the interventricular septum, or sometimes just ventricular septum.

24:59 But how would you know from the outside where that wall is exactly located? Well, as you can see here, this surface here or the epicardium has a little bit more fat and you can faintly make out a little vessel or two in there, which we're going to learn is a very particular type of coronary artery lies in there, a very important one.

25:21 So that's a landmark we can actually see externally and know that we're separating the right ventricle from the left ventricle at about this area.

25:29 And again the heart's a little tilted so that the pointy part of the heart or cardiac apex points down into the left.

25:39 Now if you get into learning about congenital heart diseases, you'll learn that there are variations to where that apex can point.

25:47 And other sorts of things might make that pointy apex less pointy.

25:51 For example, if a heart dilates in something like heart failure or dilated cardiomyopathy.

25:57 But in our typical anatomic situation, it's this pointy part of the left ventricle that points down into the left.

26:08 Now we left off with our left ventricle, which is receiving this oxygenated Needed blood, very recently oxygenated blood from the left atrium, and then it's going to be pumping out the ascending aorta before it starts to arch as the aortic arch, and then descend somewhat on the left side of midline as the descending aorta. And before it does that, it's going to give rise to some very important vessels, such as the brachiocephalic trunk.

26:40 It's another thing where if you kind of break down that word, it's helpful to know what it's doing.

26:45 Brachiocephalic brachium meaning arm, cephalic meaning head.

26:51 So that in turn is going to give rise to our common carotid supplies, the head and neck and our subclavian artery that supplies the upper limb.

27:01 Now, as you keep going, the branches for those same vessels on the left side come directly off of the aortic arch.

27:08 We have the left common carotid artery and then the left subclavian artery doing the same thing. It's just that the right ones come off of this trunk.

27:19 And if we were to open up the aortic valve, we would see and then sort of, like, cut through it and then open it up to see it all displayed in front of us, we would see three little half moon or semilunar shaped valves that help prevent backflow from the ascending aorta back into the left ventricle.

27:42 And we would notice on the right cusp a little hole called the right coronary ostium.

27:49 Ostium is just our fancy anatomy word for hole.

27:53 And this is the opening for a right coronary artery.

27:59 Similarly, on the left coronary cusp, we would see sort of the left cusp of the aortic valve. We would see a hole called the left coronary ostium.

28:09 And that will be the opening for our left coronary artery.

28:14 And this one here, which is the posterior cusp.

28:18 You know, if you were looking from above, you would see right, left and posterior.

28:22 The other term for the posterior cusp of the aortic valve is actually called the non-coronary cusp. And you can see why it doesn't have any ostium here there.

28:31 On the other cusps. So posterior or non-coronary mean the same thing.

28:35 We're referring to this cusp of the aortic valve.

28:40 Now these ostia are very important.

28:43 As you can imagine. These are the openings, right? These are the openings into the coronary arteries, which I'm pretty sure I don't even need to teach.

28:55 You are important because the heart is a muscle, right? It's a very special type of muscle, a very unique type of muscle.

29:04 But like any other muscle, it needs oxygen that's carried through arteries to survive and keep beating.

29:10 And guess what? You kind of need a heart to keep surviving.

29:15 The rest of your body. So what we're going to do is we're going.

29:17 To look at the pathways here that some of the major coronary arteries take.

29:22 To orient ourselves here would be the right ventricle going into the pulmonary trunk.

29:27 Branching into a right and left to go to each lung.

29:32 Here's our aorta. Ascending arch.

29:34 And then disappearing as the descending.

29:37 We see a little bit of a right atrium here.

29:41 We see a little bit of our left atrium.

29:43 We can actually make out one of the pulmonary veins coming back from the lung into the left atrium here as well. In order to see this path a little bit better, we're going to cut those off.

29:56 So we've cut off the left atrium a little bit.

29:58 And we've cut off most of our pulmonary trunk here so that we can see things.

30:04 And again this is our aorta.

30:06 This is our ascending aorta, which means the aortic valve is right about here. And we can see the right coronary artery emanating from that right coronary ostium. We saw it from the inside where it's being fed with good freshly oxygenated arterial blood. And here we see it emerging and going along the surface of the heart.

30:28 The other term for surface being epicardial.

30:31 And it's going between this little groove that's formed between the right atrium and the right ventricle, called an AV groove or atrioventricular groove.

30:45 And as it's traveling along that groove, it's giving off little branches to supply, among other things, for example, the right ventricle, which needs to stay alive in order to pump blood into the lungs.

30:59 On the other side, it's slightly different because we do have a left main coronary artery we see left main because it's going to branch into two important branches, and it's going to do so fairly quickly sometimes, like less than a centimeter before it does a very important split.

31:17 And one of the arteries that splits off of the left main coronary comes down here, the anterior surface of the heart as the left anterior descending artery or.

31:31 The more anatomical description for this is the anterior interventricular artery.

31:37 And that's actually a really great name. It's probably more descriptive than lad is, because it's along that interventricular septum that we pointed out in the other image. And so we know where it's going based off of that name.

31:50 Unfortunately, clinically we don't really use that term.

31:53 You'll hear lad or left anterior descending.

31:57 So both mean the same thing.

31:59 But clinically you're really going to hear it as lad.

32:02 And again it's going to give rise to a lot of branches. As you can see, a lot of these go and supply the left ventricle, making it a very important coronary artery.

32:12 The other branch of the left main coronary is this one that follows more of a mirrored pathway of the right coronary just on the left side.

32:22 And that's the circumflex artery.

32:24 And much like the right coronary artery, it's going along the AV groove.

32:28 This time just between the left atrium and the left ventricle.

32:32 And then both right coronary and circumflex arteries are going around and sort of disappearing from our point of view to the posterior aspect of the heart.

32:42 So in order to see that continuation, we're going to flip around to the posterior surface where we see the continuation of the right coronary artery here still giving rise to branches such as this one at the sort of border between anterior and posterior, we call it the right marginal branch, sometimes also called acute marginal branch.

33:08 Unfortunately, that's not a great description.

33:11 You know, unless you remember that acute means. Right.

33:13 It's kind of better if we use right marginal branch and then it eventually, although it's a little obscured here from our IVC, it's going to feed into this artery that's going to travel on the posterior aspect of the interventricular septum.

33:32 Hence the anatomic name posterior interventricular.

33:36 But again, even though that's descriptive that's more of an anatomy textbook name.

33:41 It's not really our clinical name.

33:43 You're usually going to hear PDA or posterior descending artery.

33:48 So again posterior and anterior interventricular really gets you honed in on where these are located.

33:56 You just have to know that they have different more clinically used names such as Lad or PDA. Now in this situation, we saw the right coronary supplying this posterior descending artery, but we didn't talk about the left.

34:14 So that circumflex artery is coming around doing the same thing, giving off branches over on this side the corresponding left marginal branch or obtuse marginal. So again acute marginal versus obtuse marginal are terms you may hear.

34:32 It's just unfortunate that unless you memorize it you don't know what that means.

34:36 Right. Marginal and left marginal.

34:37 Sure. We just have to be aware that they have these synonyms sometimes.

34:43 But what we see is that in this particular heart, the circumflex artery coming from the left doesn't continue on to form our PDA, and instead it's formed by the right coronary artery.

34:57 And this is the more common arrangement in most human hearts.

35:01 And we say that it's right dominant.

35:04 So if you ever hear that term, this is what it means.

35:07 It means the coronary anatomy is such that the PDA is supplied by the right rather than the left. If it was the opposite and it was supplied by the circumflex, we would say it's a left dominant heart.

35:19 And as you can imagine, we talk about that because there's clinical significance. Right. Because say you have a right dominant heart.

35:28 Well, if you have some sort of occlusion of the right coronary artery, well, that actually is going to be a lot worse than if it was a left dominant heart, because that is the artery that was supplying all of this posterior aspect of the heart.

35:43 Okay. So that's a very brief kind of overview.

35:49 Um, maybe review, maybe preview depending on where you are in your anatomy studying.

35:55 Um, but how does this help us with a differential diagnosis? Like how are we going to connect these facts of anatomy to real world clinical scenarios? Well, for now, pretty much wherever you are in your training, you want to think of all of the anatomical location locations that could possibly be the source of pain. So, you know, we typically tell, for example, first year, um, PA and MD students think very broadly.

36:21 We want a very, very, very broad differential.

36:23 Want you to think about as many possible things as you could.

36:27 Eventually, as you progress through your training, you're going to want to refine your differentials, to think about which things are particularly common, as well as which things are particularly dangerous. And that helps you prioritize your differential diagnosis a little bit more.

36:43 And yes, while heart is definitely on the differential diagnosis, especially because of this dangerous part, it's not the only structure that should be on your differential diagnosis.

36:54 And by the way, I purposely put DH just in case some of you haven't seen that shorthand kind of get you introduced to some of this, um, medical shorthand, uh, that we don't always describe.

37:05 So that's just for differential diagnosis.

37:09 Now again, we're going to use our clinical history in combination with our anatomy knowledge to help us arrive at a diagnosis.

37:16 Now we're not going to talk about all of the diagnostic procedures you might go through to really nail a diagnosis.

37:23 It's really just going to be an overview to connect the anatomy to chest pain.

37:29 So here are some clinical histories we'll go over and kind of think about where could we have some anatomic locations that correlate with this pain.

37:39 We'll start with the one that you probably always want to have on the top of your mind anyway, which is a clinical history or really a presentation that is something like a crushing substernal meaning deep to the sternum.

37:55 Pain also kind of means sort of vaguely localized that radiates out to the shoulder, for example. Well, you know, a single sentence description of a patient's chief complaint is not enough to make a diagnosis.

38:12 Of course. Otherwise. Boy, this whole job would be a lot easier.

38:16 But for today, we're going to say, well, that kind of puts us in that cardiac, uh, world where we really want to rule out the cardiac stuff.

38:25 Probably first, because that's probably the most lethal of the options on our differential diagnosis.

38:33 And you probably have heard of coronary artery disease as one of those main causes of cardiac chest pain, especially really worrisome dangerous cardiac chest pain.

38:44 So if we go back to those coronary arteries we were just looking at and we were to do a cross section, we would hope we would see something like this where we have a widely patent coronary artery, where blood is flowing just like it should.

39:00 And if we really drill down and looked at the wall of the artery, we would kind of make out there's a thin inner layer, a broad red layer here, and then a thin pink layer on the outside.

39:13 And those are three layers of the heart that are sorry of the.

39:22 Intima. Thin intima. We have.

39:29 Muscle and then very thin adventitia or outer connective tissue area.

39:34 And one of the key things when it comes to most forms of coronary artery disease is that that intima is really not much more than a layer of cells called endothelium, which means things just float right over them, things like red blood cells.

39:48 The problem is when we start to develop atherosclerotic coronary artery disease.

39:55 As you can see here, in the early stages of atherosclerotic cardiac or coronary artery disease, that intima starts to get very thick with this yellowy stuff.

40:08 Atheroma means gruel, sort of like this weird oatmeal ish thing.

40:12 And it's this gruel of like, lipids and macrophages and other things that you'll learn about in your histology or pathology courses.

40:20 But for our purposes, among other things, the thing we're worried about is the fact that that intima layer is starting to push into the space where blood flows, called the lumen.

40:30 And it gets more and more compressed, and we're reducing the ability of blood to flow through there. And where is blood flowing to? Well, the myocardium or the heart muscle that's doing all of the work to supply our body essentially with Oxygen.

40:48 Oxygenated blood. So a typical situation as these coronary arteries get very, very narrow is you really have a limitation on the supply side of myocardial oxygenation.

41:05 So that means if someone has a very narrow coronary artery and then, you know, they realize they're late for their bus and they have to go run and catch their bus. Now they have this increase in demand that their supply can't keep up with.

41:19 They might get angina or chest pain as a result of the ischemia, or lack of blood flow to the muscle supplied by this occluded or nearly occluded we would say stenotic coronary artery.

41:35 And then even worse, the thing we really worry about, probably at the top of our differential with the chest pain is, say, a piece of this plaque breaks off.

41:45 That's going to be even worse, because now, very acutely, that can cause the blood in here to clot or form a thrombus.

41:53 And then instead of having limited supply, you suddenly have no supply to a given region of the heart. And instead of being ischemic, meaning low on oxygen, you have none. And you infarct meaning that tissue necrosis or dies from lack of oxygenation. And that's a myocardial infarction or MI or heart attack.

42:22 And another thing that ties in with the anatomy is, for example, interventional cardiologists will use the knowledge of the coronary artery anatomy to go in to these coronary arteries to find these plaques and deliver a stent with a catheter, which can then be deployed or opened by inflating the little tiny balloon. As you can see, that pushes open and pushes the plaque away so that you can restore blood flow to these areas that were otherwise compromised by this atherosclerotic plaque.

43:02 And then you can do things like angiography where you inject a little bit of dye, for example, here at the right coronary ostium and see the dye go all throughout the coronary tree to make sure there's no occlusions there.

43:17 And that's basically in reverse.

43:19 How you would diagnose something like an occlusion in the first place is you would not see all of these branches appear.

43:25 One of them would be blocked off.

43:27 And again, you're using your knowledge of how the right corner coronary artery travels in this AV groove and wraps around to the posterior surface.

43:36 And you have to know that anatomy pretty well, because on these angiography studies you don't really get to see much besides the coronary arteries, because they're the only ones getting this special dye that makes it visible.

43:49 Okay, now that's that's a classic thing.

43:51 When you think chest pain, that's probably the first thing you thought we'd be talking about, right? Let's talk about some other things that might present slightly different.

44:00 And let's say maybe we've ruled out heart attack or cardiac causes of chest pain.

44:06 We can kind of move down the differential.

44:08 Um, you know, we've taken care of the most concerning things.

44:11 Well, let's say we get a different sort of presentation. Let's say there's a sharp, stabbing pain that's worse when inhaling or breathing deeply, such as with laughing or coughing.

44:23 Now, that's going to be pretty different, right? The nature of that complaint, the nature of that pain is, is a little different than the last presentation. And one of the key things we'll focus on is it's worse with inhaling.

44:37 Well what's going on with breathing? Well, we already said the diaphragm contracts.

44:41 The lungs inflate with oxygen as you breathe in.

44:46 The diaphragm relaxes.

44:47 You have elastin in your lungs that forces the CO2 out.

44:51 Key thing is the lungs are expanding and contracting.

44:54 Right. And that brings us back to the idea of pleura.

44:58 Right. So we said the pleural cavity has a little bit of pleural fluid to reduce friction in there. So this expansion contraction the rubbing of visceral and parietal is very smooth frictionless thing.

45:11 But what if you have inflammation of that pleura such as pleuritis say from a viral infection. Well, you can imagine that's something where movement such as with breathing is going to irritate it more.

45:25 And so that is a way to tie in a complaint, a chief complaint or a clinical presentation.

45:31 A little more with the anatomy.

45:33 Knowing about the anatomy of the pleura helps us think, oh, you know, that could be something that's Pleuritic chest pain.

45:41 And there are other causes of pleuritic chest pain and other ways you could damage the pleura. For example, if there's trauma that disrupts the parietal pleura and connects it to the outside atmosphere, atmospheric air, well, you could have something called a pneumothorax, a very particular type called a tension pneumothorax, where every time you breathe in air is going into the pleural cavity instead of the lungs, and therefore you can kind of collapse that lung.

46:13 Now, that doesn't really fit with kind of our scenarios we're thinking of.

46:17 Because, you know, if you have trauma that is creating a space between the pleural cavity and the outside world, they probably come in complaining about the knife in their chest rather than saying, I have chest pain.

46:27 So that'd be a little more obvious.

46:30 Something a little less obvious would be if they have a spontaneous pneumothorax from a rupture of their lungs, a rupture of their visceral pleura, and then air is going out from the inside the lungs into the pleural cavity.

46:45 In a typical situation for that might be someone who has COPD or emphysema, where they get these thin, dilated cystic airspaces along the surface of the lung called subpleural blebs.

47:03 It's just what it sounds like. It's a little bleb, just like a little tiny tight balloon right along the surface of the pleura that can rupture spontaneously.

47:12 And again, get another form of pneumothorax.

47:15 Pneumo meaning air. So air in this cavity where you shouldn't have any air, you should typically just have a small amount of fluid.

47:27 All right. So yet again a slightly different presentation here we're going to have the pain described as burning still substernal.

47:37 So we're like, okay, well, location wise that doesn't help me too much.

47:40 But burning pain and difficulty swallowing, it's like, okay, well, this is a little different than these other two.

47:48 And now instead of being related to breathing, it's being related to something digestive.

47:53 So we might think more along the GI system or digestive tract.

47:58 And we know we really don't have a lot in the chest area that's digestive besides the esophagus. So our minds are probably going to jump to the esophagus.

48:07 And we're probably going to jump to this picture we saw where we talked about the lower esophageal sphincter that protects the opening from the esophagus into the stomach.

48:19 Now, the stomach, of course, is not in the chest.

48:22 It's below the diaphragm in the abdomen.

48:25 But it's got these different parts.

48:26 And when you learn about physiology or histology, you'll learn that there's some special types of mucosa or epithelium that are at the very initial and ending parts of the stomach.

48:39 In particular, for our purposes, the cardia has some specialized glands, and those specialized glands are there because the stomach is full of acid, and the esophagus and duodenum on the opposite end are definitely not meant to handle stomach the way the sorry to handle acid, the way the stomach is.

48:59 So at the beginning and ends, we have some specialized tissue to sort of like neutralize things which help in conjunction with the lower esophageal sphincter. In this situation, to protect the esophagus from acid.

49:14 Problem is, if that lower esophageal sphincter doesn't close properly, we can get stomach acid going backwards up into the esophagus, something called Gerd.

49:29 You might have heard that term Gerd stands for Gastro esophageal reflux disease.

49:36 And so that reflux of acid up into the esophagus is very damaging because the esophagus is really made for handling mechanical stress.

49:48 So a chewed food bolus traveling all the way down to the stomach, it's not adapted to handle acid the way the stomach is.

49:57 Again, something if you learn the histology of the GI tract will make a lot of sense.

50:02 But long story short, the stomach is or sorry, the esophagus is not meant to handle this, and that acid is very damaging, makes it very inflamed, and it can be very painful.

50:13 And not only can it be painful, but if it's chronic and goes on for a long time, eventually in a subset of patients, that mucosa is just going to give up and actually turn into a different type of mucosa, go from one epithelium to another type of epithelium, something called metaplasia.

50:34 And a subset of those patients, unfortunately, could be the first step towards carcinoma or a cancer of the epithelium.

50:43 So these are things happening more on the histologic level.

50:47 But it's a way to correlate all the way from a patient's clinical presentation to anatomy to histology even. But that will be a real common example of GI related chest pain.

51:03 And then finally something that's like even more different, but probably something we would rule everything out first.

51:09 But what if we have parasternal para meaning next to the sternum with tenderness to palpation? That's our fancy word for saying hurts when you touch it.

51:21 Now that's very different than these other things, because these were pains that, you know, were either poorly localized or could cannot be directly palpated or touched because they were deep, they were in the chest cavity.

51:35 Right. Well, when you can palpate it, that's actually kind of a good sign when it comes to chest pain, because what are the things we can palpate or touch.

51:45 Well we're going back to that outer chest wall when we talked about the sternum and the costal cartilages. Well these costal cartilages form little joints with the sternum sternum joints.

52:02 Chondral is just another word for cartilage.

52:06 And same thing where that costal cartilage meets the ribs, sort of a costochondral joint.

52:13 Again just means rib cartilage joint.

52:16 You could have say costochondritis inflammation of these joints.

52:22 And again inflammation of these joints being a more musculoskeletal issue rather than GI or respiratory or cardiac is something you can actually touch.

52:33 You can localize the pain very well and you can reproduce it with palpation on a physical exam. And fortunately, that's something that's going to be less worrisome than all the other ones, and going to be something that once you've ruled out the scary things, you can kind of get down to this level and hopefully find that it's in this area that corresponds with their pain and the way they described it. So in summary, because we're running low on time here, we're going to always keep in mind all of the anatomy and basically break up our differential at first by anatomic location.

53:12 And again, as you get further into these conditions, you're going to start sorting them by the seriousness of the conditions, for example, myocardial infarction.

53:21 And well a lot of those cardiovascular ones are very serious.

53:25 Very, very potentially life threatening pulmonary.

53:31 There are various things that are going to be more life threatening than others. Some are a little more slow, some are a little more emergent, like a pulmonary embolism.

53:39 And then some are going to be lower on the differential, even if they're common causes of chest pain, such as a costochondritis, for example.

53:47 So you're going to eventually combine your anatomic knowledge with the conditions that are related to these anatomies by how serious they are.

53:59 And again, knowing your chest anatomy is the foundation for all of this, even though you're going to get into the pathology of these things and how to work them up and eventually how to treat them, of course, they're really going to be rooted in knowing everything that's in that space between the neck and the abdomen. And that means not all chest pain is going to be cardiac pain.

54:19 That's an important part of it.

54:20 But it's not the full story.

54:22 And again, even then you're going to sort things eventually into the things that scare you the most to the things that scare you the least.

54:31 And I think I will hand that over to Nurse Liz.

54:35 That's the last thing that I have.

54:42 Perfect. That's all. Thank you so much, Doctor Cancelmi.

54:46 Um. I know you have to run.

54:48 Um, if you want to do that, uh, if everybody wants to, I all the whole time people are like, this is so helpful.

54:53 So everyone tell them this is what he comes back.

54:56 Um, and if you want more about him, we'll talk about that in a second.

54:59 But thank you so much. That was so helpful.

55:01 Um, I'm going to go over some of the questions.

55:03 Um, but thank you. We really appreciate it.

55:05 That was. Thank you. Thanks so much for having me.

55:08 And, uh, hope to see you, at least in the form of my recordings in the future. Yes. Take care everybody.

55:15 Thanks. Bye. All right, so I have flagged a couple questions.

55:20 We're going to answer them in just a second. Um, I can answer most of them. I'm a nurse practitioner.

55:25 Um, so I'm definitely not Doctor Solmi, but I have some insight on some of the things that we were talking about in the chat, and I can hang for a few, so if you have any questions, um, you can let me know.

55:38 Uh, and thanks everyone for being here.

55:40 I know these these are fun because they're live and we get to kind of like, get your questions, see what's going on. Again, if you have ideas for future things like this, let us know.

55:49 Uh, if you like this type of, like format, like the anatomy of chest pain.

55:54 Looking into that, uh, some people recommended radiology how to review. Um, you know, like x rays.

56:00 We could do an x ray series.

56:01 I think that could be fun.

56:02 So let us know. This will all be recorded.

56:05 I've seen a lot of questions about that.

56:07 Uh, we're going to email it out to everybody right after this.

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56:27 And if not we'll have to get Doctor Salmi back here so he can help us out.

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56:39 And he go, he does things like this, but just in so much more depth.

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58:51 Uh, if that sounds like it would be helpful, it's something I wish they had when I was in school. We are offering a 50% off for coming to this, so. Yay! Uh, it code at checkout will just be anatomy 50.

59:03 That. Just to give you a ballpark idea.

59:05 Oh, and it says three months, but it's off of any of them. So there's monthly plans for people who are like, I just need like one month until I'm done with school, three months for like, I like, I want this for a semester or give me the whole year for 12 months gets cheaper the longer you commit to.

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59:56 I've done nursing school and in school, and it's it's a lot friends.

1:00:00 Um, and I know those of you in like PA and med school like it is equally it's just a lot. Right. It's a lot.

1:00:07 Um, so I am going to plop up here, let's see if we can make the technology work.

1:00:12 We do have. These are always available for like, little freebies. I threw these in here because these I think are helpful. Um, if you're in med school, we have a med school survival guide.

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1:01:41 Um so questions. So I'm going to bring up some of the questions that we had during the presentation. Um, and let us go back.

1:01:51 Uh, Angie said real quick, can I apply the anatomy 50 code to the membership I signed up for already? I'm in the seven day trial period. Yes, I would email customer service.

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1:02:52 Sure. So we can definitely make those, um, going forward.

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1:03:40 So that's awesome. Um let's see.

1:03:42 Okay. So we had some questions about um, is there a anatomical basis explaining the nature of pain like crushing, sharp burning, etc.? So, um, from my understanding of it, again, this is going to be like very broad. It just depends on the type of nerve endings that that organ right, is going to have and the injury afflicted.

1:04:08 So if you have a really large area, um.

1:04:12 Right. Where things weren't like nerve endings right in your skin.

1:04:16 I'm explaining this horribly. Bear with me. Anatomy is not my.

1:04:20 Not my forte. Different types of injuries are going to affect different nerves because we have different type of nerve endings. And nerves are present in different ways, in different tissues. Right? Your fingers, your skin.

1:04:31 So many nerve endings.

1:04:32 Because we want to be able to feel everything in our surroundings.

1:04:35 When we injure them, they're going to scream.

1:04:37 They're going to hurt really bad. There are so many nerve endings in some of your more internal organs. There's not a whole lot.

1:04:43 So depending on how it's injured, if it's like poked really hard, it might be more like, ooh, like even if it's a really sharp poke, it might be a more diffuse pain because there's just not as many nerve endings there.

1:04:55 Right. So it's just mostly it depends on how widespread is the injury and what type of nerve endings are there that are there.

1:05:02 And what shape are those nerve endings in, right? Because you could have a condition such as diabetes, which then hinders how those nerves, how healthy those nerves are.

1:05:12 And so then we get into things like, oh, you're having like, um, pain even when there's no stimulus or you're not feeling pain, right. Like with, like if you have a lot of damage in your foot and the nerves in your feet, then we're having no pain when there should be pain, even if there's a wound. So a lot of it just has to do with the nerves where they are and how healthy they are and how many there are in the tissue that was injured.

1:05:36 Um, let us see. The, um.

1:05:40 Johan asks. They had they said the heart has coronary arteries for supply of oxygen.

1:05:46 The lungs have a similar system where they supplied via the pulmonary veins on the go.

1:05:50 So they do have a blood supply.

1:05:53 The lungs actually like bring in the oxygen.

1:05:55 Remember through you'll go through the bronchus and then the bronchioles and then all the way through like the little alveoli, the air sacs.

1:06:01 That's how the air actually gets brought in. But they do have a blood supply kind of innervating the alveoli, kind of like giving the actual tissue a little bit of blood supply.

1:06:11 I hope that answered your question. Um, and then, uh, Killian said, why does pain from the heart? Um, why is that conveyed to the medial side of the arm? Um, the nervous pathway of this referred pain.

1:06:25 A lot of the times with chest pain, kind of like Doctor Salami was saying, is you have pain. Your your brain can get pretty confused about sometimes about where the pain is actually coming from.

1:06:37 Because remember how we were talking about the not all of our organs have a ton of nerve endings. They might have a great blood supply, but they might not have a ton of nerve endings. And the messages can get really mixed.

1:06:48 So sometimes your brain interprets pain that's actually from like down in your abdomen. It'll be up here in your shoulder. And it's because there's a nerve pathway that the pain is traveling along and it's very nonspecific.

1:07:01 You'll hear that term a lot.

1:07:02 And so usually when you're having arm pain because of actual chest pain, it's because it's along the same nerve pathway.

1:07:10 And your brain just got its signals mixed up in there because there was not a lot of differentiation in terms of, you know, your because your nerves send a message to your brain, which then has to interpret it and send it back out. And sometimes it's just not very good at doing that.

1:07:24 And this is one of those situations where there's a lot happening and it's just it's just not the best at figuring it out here in this case.

1:07:31 Um, and then let me see.

1:07:34 Um, we'll finish that one out there.

1:07:37 Diego asks, are there parts of the myocardium better oxygenated than others, or some parts that suffer more from ischemia than others? So I'll be honest, I'm not sure about the first part, which is not good considering I was a I worked in pediatric cardiology for like six years, so probably should know that.

1:07:56 Um, but in terms of like, are some parts of the heart more affected by ischemia? Yes. So if you or I guess it just the way that those injuries will come be reflected will be different.

1:08:07 So the different parts of your heart pump to different areas.

1:08:11 Right. And so the thing directly downstream from the injury and right before the injury are the things that are going to be the most effective. And usually we see the most Issue.

1:08:21 Right. If like a big chunk of your left ventricle.

1:08:25 Right. The blood supply to your left ventricle, which is the main pusher of all that blood, it goes through your heart, it goes through your lungs, it comes back. It gets to the left ventricle where it's going to be launched out into the whole body. Well, if your biggest pump gets a booboo, that's real bad.

1:08:40 Right. And you're going to see a lot of effects of it eventually.

1:08:43 Everything kind of adds up.

1:08:44 Because even if you injured, let's say like the right atrium, well, at first your body might be able to compensate a little bit.

1:08:51 You know, it's not the biggest pusher of things. It's a little bit of a pusher of things. But it's not the left ventricle.

1:08:57 Right. But eventually that right ventricle having damage, it's going to start backing up. And it's not going to be able to pull in the blood into the heart. We're going to have backup. That's when we're going to have edema and all sorts of like leg swelling and ascites.

1:09:09 And that blood's going to be backing up in other areas of the heart because it can't get pumped into the heart. So on initial glance, yes, it would seem that like areas of the left ventricle, that's going to be way more problematic. Maybe the right ventricle second most, because if you're not pumping it to the lungs, we're backing up into the right atrium. So probably the ventricles are the big two where you're first like, oh man, that's not good. But eventually that's how we get into heart failure, right? Where one thing kind of leads into the degeneration of something else, and it kind of just, you know, cascades into a whole, a whole hot mess, if that makes sense.

1:09:45 Um, so there we go. If hopefully that helps.

1:09:48 That wasn't a doctor answer, but that's where it is.

1:09:52 Um, let me see. Um, where we have in terms of getting the certificate, we will email one out.

1:10:00 If I'm able to make one, we'll leave it at that, and the next time we'll try to have one.

1:10:05 But, um, we will work on that.

1:10:09 So if there's going to be a certificate, we will I will figure out how to email it out. People are going to watch this and they're going to be like, Liz, why are you promising things? Why are you saying things that we don't even have? Sorry. Um, so there we are.

1:10:23 Okay. Thanks for coming, everyone.

1:10:25 I really appreciate it. Christian. I don't know when the next event is.

1:10:28 Um, we usually plan these, like, a month or two in advance.

1:10:35 We don't have any planned for like, a joint med and nursing one.

1:10:39 We wanted to get feedback from this, which is actually, as soon as this closes, you're going to be led to a quick survey to kind of help us figure out what kind of content do you want to see in these live events.

1:10:49 Is something like this helpful? Um, what kind of topics would you like to see going forward.

1:10:55 Uh, that can actually help us plan these, because we don't want to give you an event that you're like, this is boring, and I hate it. Right.

1:11:00 We want to do something that you're going to gain value from, be able to take it away and implement it into practice, um, in your clinical setting or wherever you are. So if you could take that survey, that would be a delight.

1:11:11 Um, we have here's a link again to the 50% off plan.

1:11:16 If you do want to check out Lecturio.

1:11:17 Um, Doctor Salmi is a great lecturer on there, and there are so many others for pretty much all the topics you're going to see in school.

1:11:24 Again, it's just going to give you that like one stop shop of watch the Lecture quiz you every day to keep it in your mind, and then you can set up question banks to get you ready for your test or whatever board exam that you have next.

1:11:37 Um, so yeah, there we go.

1:11:38 And you can always go to our social media too, if you want to leave us recommendations there. You can email us.

1:11:43 I see lots of recommendations coming in for like cardiology and surgery, neurology. Um, we do have a ton of those topics on the, uh, Particularly on the med side.

1:11:53 We have whole playlists about, you know, surgery and radiology and all of those types of things over there.

1:12:00 And nursing has, um, actually a pretty good post op, uh, like surgical, um, interventions course too.

1:12:07 And if you ever have any questions, you can always email um customer service.

1:12:12 And they some of that might even get, you know, funneled to me. And we can figure out how we can get you the topics that you're interested in. Um, we love any feedback on, like, what you would like to see in the product. So we don't have to guess, you know, always, always better. Um, lots of requests I see for, like, a physical exam, um, assessment.

1:12:32 That would be great. I think.

1:12:34 I love the idea of physical exam.

1:12:36 I'm going to write it down. Um, I have lots of notes from.

1:12:39 Just like all the input that you guys have been giving in here so far.

1:12:42 Um, and I very much appreciate that.

1:12:45 So here we go. Um, here's the emails that you can use if you need them.

1:12:49 Um, if you have feedback, questions, anything like that.

1:12:52 Katie. Yes, the one year plan, everything.

1:12:55 The 50% off code works for everything.

1:12:56 We put three months in the slide because that tends to be, uh, like what people sign up for the most.

1:13:02 And so we just, like, threw it in there. But it could be for the one month. It could be for the three month, it could be for the 12 month. If you're in med, it could be for like the three year because I know we have that as an option. So whatever you would like you can use it for that.

1:13:12 Um, the discount code should be available for a few days, but if you happen to miss the window, um, you can always email them.

1:13:19 They're pretty flexible, usually with stuff like that. If you're like, I went and I forgot, they'll be like, oh, you must be related to Liz and then they'll probably give it to you. So, um, that is that, like I said, email us if you have any questions. Thank you so much for coming today. And please fill out the survey, because it really does tell us what you'd like to see if this was helpful and what we can do for you in the future.

1:13:40 I hope you have a beautiful rest of your day and, uh, know a little bit more about the heart.

1:13:46 Thanks for coming by.