Pacemaker Learning Package
Intensive Care: Learning Packages Intensive Care Unit Pacemaker Learning Package
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- Điều hướng trang này:
- Cardiac Valves
- The Heartbeat
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Intensive Care: Learning Packages Intensive Care Unit Pacemaker Learning Package LH_ICU2016_Learning_Package_Pacemaker_Learning_Package 4 | P a g e ANATOMY Figure 1: www.nursing-lectures.com/2011/01/cardiovascular-system-introduction The Heart • the heart is a cone-shaped, muscular organ located between the lungs behind the sternum. • The heart muscle forms the myocardium • the inner lining of the myocardium is called Endocardium and the outer layer cells is called the Epicardium. • The pericardium (visceral) is the outer membranous sac with lubricating fluid. • The heart has four chambers: two upper, thin-walled atria, and two lower, thick-walled ventricles. • The ventricles are the chambers that eject blood in to arteries. The functions of the atrium are to receive the incoming blood from the vein Liverpool Hospital Intensive Care: Learning Packages Intensive Care Unit Pacemaker Learning Package LH_ICU2016_Learning_Package_Pacemaker_Learning_Package 5 | P a g e The septum is a wall dividing the right and left sides of the heart Coronary arteries are the vessels that supply blood to the heart muscle. Cardiac Valves: Cardiac valves permit blood to flow in only one direction through the heart • Atrioventricular Valves: 1] Tricuspid valve: separates the Right atrium from the Right ventricle 2] Bicuspid valve [Mitral valve]: lies between the Left atrium and Left ventricle. • Semi lunar Valves: 1] Pulmonic valve: is the valve between the Right ventricle and the pulmonary artery. 2] Aortic valve: is the valve between the Left ventricle and the aorta. The Heartbeat • Each heartbeat is called a cardiac cycle. • When the heart beats occur, the two atria contract together, then the two ventricles contract; then the whole heart relaxes. • Systole is the contraction of heart chambers; diastole is their relaxation. • The heart sounds, lub-dup, are due to the closing of the atrioventricular valves, followed by the closing of the semi lunar valves. tải về 1.43 Mb. Chia sẻ với bạn bè của bạn:
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