The heart is a muscular organ the size of a clenched fist situated in the middle of the chest tilted slightly to the left. The heart receives its own oxygenated blood supplied by the coronary arteries and the coronary veins that take away the deoxygenated blood. The heart is made up of four chambers the left and right atrium and the left and right ventricle. The oxygenated blood travels from the lungs through the pulmonary veins, the pulmonary vein are the only veins in the body that carry oxygenated blood to the heart, the blood then enters the left atrium the blood is then pushed through the bicuspid valve, where the blood now enters the left ventricle where the blood is then pumped through the aortic valve into the aorta where the oxygenated …show more content…
(Steve Parker 2007) The hearts wall are made of a special muscle known as cardiac muscle this type of muscle is only found in the heart because of its uniqueness, the muscle needs the ability to constantly contract without becoming weak or tired and to maintain this the muscle needs a continuous supply of oxygenated blood from the coronary arteries. The left and right side of the heart is divided by the septum, the septum also does not allow oxygenated and deoxygenated blood to mix and also helps support the …show more content…
The smallest of all vessels are the capillaries which are one cell thick, the pressure is very low and gas exchange happens in the capillaries. A myocardial infarction (heart attack) happens when coronary arteries get blocked this effects the supply of blood and oxygen to this part of the heart which can cause the heart muscle to die off from lack of oxygen and nutrients, if the muscle has died it will be replaced with scar tissue. Atherosclerosis is where arteries become clogged with plaques or atheroma which are cholesterol and excess fatty substances, these cause the arteries to harden and do not let the proper blood supply flow which can stop organs functioning properly. These plaques can rupture which causes a blood clot, the blood clot then blocks the hearts blood supply causing the hearts muscle to be deprived of oxygen and may result in the muscle dying.After a heart attack the hearts function may not be the same some complications can be Arrhythmia (abnormal heart beats) such as Tachycardia (heart beating too fast) Bradycardia (too slow) or Atrial Fibrillation (irregular heart