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Cardiac physiology or heart function is the study of healthy, unimpaired function of the heart: involving blood flow; myocardium structure; the electrical conduction system of the heart; the cardiac cycle and cardiac output and how these interact and depend on one another.
The wall of the heart is made up of three layers: epicardium, myocardium, and endocardium. [8] The heart pumps blood with a rhythm determined by a group of pacemaker cells in the sinoatrial node. These generate an electric current that causes the heart to contract, traveling through the atrioventricular node and along the conduction system of ...
The heart is a muscular organ situated in the mediastinum.It consists of four chambers, four valves, two main arteries (the coronary arteries), and the conduction system. The left and right sides of the heart have different functions: the right side receives de-oxygenated blood through the superior and inferior venae cavae and pumps blood to the lungs through the pulmonary artery, and the left ...
The cardiovascular centre affects changes to the heart rate by sending a nerve impulse to the cardiac pacemaker via two sets of nerves: sympathetic fibres, part of the autonomic nervous system, to make heart rate faster. the vagus nerve, part of the parasympathetic branch of the autonomic nervous system, to lower heart rate.
The heart is located in the middle of the abdomen with its tip slightly towards the left side of the abdomen. Disorders of the heart lead to heart disease and cardiovascular disease and can lead to a significant number of deaths: cardiovascular disease is the leading cause of death in the U.S. and caused 24.95% of total deaths in 2008. [19]
Heart attack. A heart attack results from a sudden plaque rupture and formation of a thrombus (blood clot) that completely blocks blood flow to a portion of the heart, leading to tissue death . CAD can also result in heart failure or arrhythmias. Heart failure is caused by chronic oxygen deprivation due to reduced blood flow, which weakens the ...
This is an accepted version of this page This is the latest accepted revision, reviewed on 16 February 2025. List of organ systems in the human body Part of a series of lists about Human anatomy General Features Regions Variations Movements Systems Structures Arteries Bones Eponymous Foramina Glands endocrine exocrine Lymphatic vessels Nerves Organs Systems Veins Muscles Abductors Adductors ...
The conduction system consists of specialized heart muscle cells, situated within the myocardium. [3] There is a skeleton of fibrous tissue that surrounds the conduction system which can be seen on an ECG. Dysfunction of the conduction system can cause irregular heart rhythms including rhythms that are too fast or too slow.