<unk>  is the<unk>  of blood in the blood vessels that supply the heart muscle (myocardium).<unk>  arteries supply oxygenated blood to the heart muscle. Cardiac veins then drain away the blood after it has been deoxygenated. Because the rest of the body, and most especially the brain, needs a steady supply of oxygenated blood that is free of all but the slightest interruptions, the heart is required to function continuously. Therefore its<unk>  is of major importance not only to its own tissues but to the entire body and even the level of consciousness of the brain from moment to moment. Interruptions of<unk>  quickly cause heart attacks (myocardial infarctions), in which the heart muscle is damaged by oxygen starvation. Such interruptions are usually caused by<unk>  ischemia linked to<unk>  artery disease, and sometimes to embolism from other causes like obstruction in blood flow through vessels.
Coronary circulation
Cardiac cycle
Arterial tree
Electrical conduction system of the heart
Myocardial contractility
Autonomic nervous system
Limb perfusion
Vagal tone