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The heart functions as a pump and acts as a double pump in the cardiovascular system to provide a continuous circulation of blood throughout the body. This circulation includes the systemic circulation and the pulmonary circulation. Both circuits transport blood but they can also be seen in terms of the gases they carry. The pulmonary ...
Interruptions of coronary circulation quickly cause heart attacks (myocardial infarctions), in which the heart muscle is damaged by oxygen starvation. Such interruptions are usually caused by coronary ischemia linked to coronary artery disease , and sometimes to embolism from other causes like obstruction in blood flow through vessels.
In vertebrates, the circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the body. [1] [2] It includes the cardiovascular system, or vascular system, that consists of the heart and blood vessels (from Greek kardia meaning heart, and Latin vascula meaning vessels).
Both of these factors affect pH and, in turn, the balance between vasodilation versus vasoconstriction in the brain. [3] [4] So, the blood vessels found specifically in the brain respond changes in dissolved carbon dioxide levels. Coronary (heart) circulation is controlled at the local level primarily by metabolic control mechanism. More ...
The blood pressure in the circulation is principally due to the pumping action of the heart. [32] The pumping action of the heart generates pulsatile blood flow, which is conducted into the arteries, across the micro-circulation and eventually, back via the venous system to the heart.
The heart did not pump blood around, the heart's motion sucked blood in during diastole and the blood moved by the pulsation of the arteries themselves. [93] Galen believed the arterial blood was created by venous blood passing from the left ventricle to the right through 'pores' between the ventricles. [90]
It does this by activating an enzyme found in the muscle cells of the blood vessels; this, in turn, signals the body to relax or widen blood vessels (a process called vasodilation), which lowers ...
Heart failure is caused by chronic oxygen deprivation due to reduced blood flow, which weakens the heart over time. Arrhythmias are caused by inadequate blood supply to the heart that interferes with the heart's electric impulse. The coronary arteries can constrict as a response to various stimuli, mostly chemical. This is known as a coronary ...