Hi, I'm Cathy with Level Up RN. This is the first video in our cardiovascular system playlist. I'll be following along with our medical-surgical nursing second edition flashcards, which are available at leveluprn.com. So our flashcards and this video series are intended to help you learn the most important facts and concepts you need to know to be successful on your nursing exams and in clinical practice. So I won't be going through every single thing that you can find on our flashcards, but I will hit many of the highlights. So in this video-- at the end of the video, I'll be giving you guys a little quiz, a little knowledge check to test your understanding of some of the information I'll be covering in this video. And I'll be doing so with all the subsequent videos in this playlist. So if you like that, be sure to leave me a comment and subscribe to our channel. I hope they're going to be really helpful, these knowledge checks. In this video and in the next two videos, I'm going to be doing an anatomy and physiology review of the cardiovascular system. And I'm doing this because I find that when you fully understand how a body system is supposed to work, it's easier to understand and think critically about what will happen when something breaks. So instead of memorizing a list of symptoms, you can really think critically about what would you expect to happen in terms of signs and symptoms if something were to go wrong. So like I said, I'll be spending this video and the next two kind of going through that review. And then after that, we will head into diagnostic tests and disorders as well. All right. Let's now do our anatomy and physiology review. So the cardiovascular system is comprised of the heart and the blood vessels. So the heart is basically a muscular pump that circulates blood throughout the body. And it pumps about 5 liters of blood every minute. So the blood will go from the heart to the arteries to the arterials, to the capillaries, and then the venules, the veins, and back to the heart. So we have a little cool chicken hint on this card, which is that arteries carry blood away from the heart. So arteries and away both start with "a" to help you remember that those arteries are what's going to carry the blood away from the heart, and the veins are going to carry blood back to the heart. So the key function of the cardiovascular system is to supply oxygen and nutrients to our body cells, and to remove metabolic waste from the body. And this really occurs at the capillaries. So, for example, oxygen will move from the bloodstream in the capillaries into the body cells. And carbon dioxide, for example, will move from the body cells into the capillaries where it will flow back to the heart, and it can be removed from the body. Surrounding and protecting the heart is the pericardium. So the pericardium is a membrane that surrounds the heart. Peri means around or enclosing. And later on in this video playlist, we'll be talking about something called pericarditis. So any time you see "itis", that means inflammation. So with pericarditis, we have inflammation of that membrane that surrounds the heart, the pericardium. So the heart wall is comprised of three layers. The outer layer is the epicardium So "epi" means upon or above. The middle layer is the myocardium. So "myo" means muscle. So this middle layer of the heart is really responsible for the pumping action of the heart. And then the inner layer of the heart is the endocardium. So "endo" means inner. Let's now take a look at the chambers and the valves in the heart. Here's an illustration from our medical-surgical nursing flashcard deck. And you can see that we have four chambers of the heart. We have the right atrium, the right ventricle, the left atrium, and the left ventricle. And we have a septum here that separates the right and left sides of the heart. So let's now talk about valves. So valves in the heart help to control blood flow and prevent blood from flowing backwards. So we have our tricuspid valve here on the right side of the heart. So if you look at the word "tricuspid", you have "ri" to help you remember that this is on the right side of the heart. So the tricuspid valve, it separates the right atrium from the right ventricle. Then we have our mitral valve over here on the left, which separates the left atrium from the left ventricle. Then we have our pulmonic valve which separates the right ventricle from the pulmonary artery. And then, finally, we have our aortic valve here on the left side that separates the left ventricle from the aorta. So let's talk about the blood flow through the heart, which is definitely important to know. So the right atrium here receives unoxygenated blood from three veins. So it receives unoxygenated blood from the superior vena cava here, the inferior vena cava, as well as the coronary sinus. That blood will go from the right atrium through the tricuspid valve into the right ventricle. And then from the right ventricle, it will pass through the pulmonic valve into the pulmonary artery, and then the blood will become oxygenated in the lungs, and return to the left atrium through the pulmonary veins. From the left atrium, the blood goes through the mitral valve into the left ventricle. And then from there, it will pass through the aortic valve into the aorta, where it becomes distributed throughout the body. Knowing that blood flow is really going to help you when we cover heart failure. And it will let you easily know the signs and symptoms of left-sided heart failure versus right-sided heart failure. Okay. It's time for a quiz. I have three questions for you. First question. What is the membrane that surrounds the heart? If you said the pericardium, you were right. Second question. What is the inner layer of the heart? The answer is the endocardium. And then, last question. What valve separates the right atrium and the right ventricle? If you said the tricuspid valve, you are correct. So remember our little cool chicken hint, the word "tri" from tricuspid. You have that "ri" to help you remember that this is on the right side of the heart. All right. If you found this video helpful, be sure to hit your like button. Leave me a comment. And if you haven't already done so, be sure to subscribe. Thank you so much for watching. I invite you to subscribe to our channel and share a link with your classmates and friends in nursing school. If you found value in this video, be sure and hit the like button, and leave a comment and let us know what you found particularly helpful.