Organ of our body

I think that heart is one of the most important organs in our body, simply because without him, nobody can live, besides heart is a organ connected with emotions and I am a person very emotional.
Heart is a muscular organ of our body, which pumps blood through the blood vessels of the circulatory sistem. Blood provides the body with oxygen and nutrients.
The location of heart is between the lungs, in the middle compartment of the chest, exactly is situated in the middle mediastinum, at the level of thoracic vertebrae T5-T8. A double membraned sac called the pericardium sorrounds the heart  and attaches to the mediastinum.
Is form for four chambers, two upper atria, the receiving chambers, and two lower ventricles, the discharging chambers. The atria open into the ventricles via the atrioventricular septum. Also has four valves, wich separate its chambers, one valve lies between each atrium and ventricle and one valve rests at the exit of each ventricle.
In average the heart in a adult size twelve centimeters of long, nine centimeters of width and six centemeters of thickness and it is true that our heart is the size of our hand in fist.
I see our heart that I wonderful organ that allows us to stay alive every day.