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The heart is a muscular organ found in humans and other animals.This organ pumps blood through the blood vessels. [1] Heart and blood vessels together make the circulatory system. [2]
The mediastinum (from Medieval Latin: mediastinus, lit. 'midway'; [2] pl.: mediastina) is the central compartment of the thoracic cavity.Surrounded by loose connective tissue, it is a region that contains vital organs and structures within the thorax, namely the heart and its vessels, the esophagus, the trachea, the vagus, phrenic and cardiac nerves, the thoracic duct, the thymus and the lymph ...
The atrium (Latin: Ätrium, lit. 'entry hall'; pl.: atria) is one of the two upper chambers in the heart that receives blood from the circulatory system.The blood in the atria is pumped into the heart ventricles through the atrioventricular mitral and tricuspid heart valves.
Cardiac muscle (also called heart muscle or myocardium) is one of three types of vertebrate muscle tissues, the others being skeletal muscle and smooth muscle.It is an involuntary, striated muscle that constitutes the main tissue of the wall of the heart.
The unusual microscopic anatomy of a muscle cell gave rise to its terminology. The cytoplasm in a muscle cell is termed the sarcoplasm; the smooth endoplasmic reticulum of a muscle cell is termed the sarcoplasmic reticulum; and the cell membrane in a muscle cell is termed the sarcolemma. [9]
A heart valve is a biological one-way valve that allows blood to flow in one direction through the chambers of the heart.A mammalian heart usually has four valves. Together, the valves determine the direction of blood flow through the heart.
In the blood supply of the heart, the right coronary artery (RCA) is an artery originating above the right cusp of the aortic valve, at the right aortic sinus in the heart. [1] [2] It travels down the right coronary sulcus, towards the crux of the heart.
The sinoatrial node (SA node) is the primary pacemaker of the heart. It is a region of cardiac muscle on the wall of the upper right atrium near to the superior vena cava entrance.