hey everyone it's nurse Sarah and in this video I want to be going over the layers of the heart so let's get started surrounding your heart is a sack called the pericardium and it acts as a protective and supportive covering that does a few things it will help prevent overstretching of your heart it helps keep out Invaders that could cause infection and it keeps your heart in place so it isn't flopping all over your chest especially during activities now the pericardium is made up of two layers the first layer which is our outer layer is known as the fibrous paric cardium and this layer is made up of a tough connective tissue hence its name fibrous which means very strong now because of its composition of this tough fibrous material it's great at providing Anchorage to nearby structures like the great vessels and the diaphragm so it keeps it in place in the media stum in addition this fibrous pericardium is going to play a huge role in preventing our heart from over stretching when we have an increase in blood volume the second layer of the pericardium is known as the Cirrus pericardium and this layer produces Cirrus fluid which plays a role with helping lubricate our heart so whenever it beats those layers don't rub up against each other and cause friction now this layer is also made up of two layers that are continuous with each other and because they're continuous with each other they help form the pericardial space which helps store the Cirrus fluid so let's take a closer look at these two layers of the Cirrus pericardium the first layer is called the paral layer of the Cirus pericardium and it comes into contact with the fibrous pericardium itself then you will see the paracardial space and then right next to that in yellow you will see the next the second layer of the Cirus pericardium which is the visceral layer of the Cirrus pericardium this is also called the epicardium which is actually one of the three layers of the heart wall it's the outermost layer so when I refer to epicardium I'm also talking about this visceral layer of the cus pericardium and this layer adheres and lines the actual heart itself so to help you remember visceral layers versus prodal layers and what structures they adhere to whether we're talking about the heart or any other areas in anatomy remember that visceral layers are always going to surround the vital organ itself visceral has VI vital has VI so these connected layers the pattle and the visceral are going to connect and fold in a way that creates a special space called the paracardial cavity or space and this area contains Cirrus fluid that helps your heart beat without friction or resistance it acts as a protective barrier to the deepest parts of your heart to protect it from infection or trauma now from a nursing standpoint you want to be familiar with the pericardium because there's a lot of diseases that affect these layers and its space for instance like a paracardial affusion this is where we have way too much fluid in this paracardial space or if we get inflammation of these layers it can lead to pericarditis and with pericarditis what you want to remember are the things that you're going to find in a patient who has this for instance you're going to hear a paracardial friction rub and this is where these layers are rubbing up against each other they're not really lubricated anymore so whenever this happens you're going to hear a specific sound it's going to sound like a grading scratching sound because those layers are just literally rubbing on each other and it's going to be heard at the left of the sternal border you're going to hear it best whenever the patient sets up and leans forward and more towards the end of expiration now circling back to the layers of the heart we just got done talking about the visceral layer of the Cirus pericardium which again is known as the epicardium which is one one of the three layers of our heart wall it's the outermost layer now under the epicardium is The myocardium which is the second layer of that heart wall and it is our middle layer so remember myocardium starts with m and middle starts with m so we know that this is our middle layer of those three layers and notice that this layer is the thickest of all the layers and it's the most unique of all the layers of the heart wall because it's made of meos sites which are a special network of bundles of cardiac muscles that cause involuntary rhythmic continuous heart contractions under the direction of our heart's electrical conduction system in addition The myocardium contains and supports our electrical structures of the heart and this layer is supplied by our coronary arteries now from a nursing standpoint you want to be familiar with this smio cardium because it's like the most essential part for giving your heart its pumping function but unfortunately this layer can be affected by disease processes a big disease process that you're going to encounter as a nurse is a mardial infarction a heart attack this is where there's been decreased blood flow through those coronary arteries where they've been Limited in their ability to deliver fresh oxygenated blood to The myocardium specifically those myocytes and those myocytes die and parts of this heart die and it limits it ability to function and pump which can lead to heart failure in addition this layer can be affected through toxins in the heart or infection leading to myocarditis so whenever you have a patient who has a my cardial infarction or myocarditis this is the part of the heart that is being affected now the next layer which is our third layer and our innermost layer is called the endocardium and the word Endo means inner so we're talking about the layer that is inside of our heart and this layer consists of an endothelium and covers the inside of our heart such as our Chambers like our Atria and ventricles and valves this layer is very smooth which allows blood to easily flow throughout the heart without problems so we don't get the formation of clots because remember if blood is impeded where it's going to stay still too long it will start to form clots but this layer is designed in a way that's going to prevent that now unfortunately problems can also arise with this layer as well especially with a condition known as ocard I so whenever you hear that term we have inflammation of the endocardium and what happens is that Invaders get into this layer but how do they do that typically how they do that is because something has entered our bloodstream it could be through an infection or IV drug use but whatever the cause is it gets inside the blood we know the blood flows through the heart and as that blood that's tainted with those Invaders flows through her heart those Invaders start to stick inside that endocardium which leads to infection now this typically affects the valves of the heart like your tricuspid or your aortic and so forth okay so that wraps up this review on the layers of the heart and don't forget to access the free quiz that will test you on this material we just covered