Systemic circle

The systemic circle goes from the left ventricle to the right atrium. From the left ventricle originates the aorta, which branches into smaller vessels gradually going to vascularize the various organs and tissues. Then from the left ventricle the oxygenated blood reaches the rest of the body. Through the capillaries oxygen (O 2 ) is transferred to the tissues and carbon dioxide (CO 2 ) is detected, so that the arterial … Continue reading Systemic circle »

Work of the heart

It consists of two fundamental moments: - diastole → filling - systole → emptying The blood flows to the atria through the pulmonary veins and the superior vena cava; the atrioventricular valves are initially open and the semilunars closed (the semilunar ones enter the large efferent vessels, pulmonary trunk and aorta). The blood then flows into the ventricles simply by gravity; when the ventricle is filled for 2/3 part the impulse (from … Continue reading Work of the heart »

Pulmonary orifice and pulmonary semilunar valve

The pulmonary orifice is located between right ventricle and pulmonary trunk, and is equipped with a valve, the pulmonary semilunar valve.The lung semilunar valve regulates the flow of blood to the pulmonary circulation . It is formed by three flaps, in the shape of a half-moon. front half-moon right and left hindquarters The valve has a concave upper face facing the lumen of the pulmonary trunk and the … Continue reading Pulmonary orifice and pulmonary semilunar valve »

Aortic orifice (or aortic semilunar valve)

The aortic orifice connects the aorta with the left ventricle. It is occupied by the aortic semilunar valve. This has a dovetail structure. It is equipped with semi-lunar valvular flaps (shaped, of course, of half-moon): - left and right anterior semilunar flaps called coronary semilunars (as there are the orifices of coronary artery origin). - posterior semilunar flap The three flaps present, at the free margin, that is, … Continue reading Aortic orifice (or aortic semilunar valve) »

Bicuspid (or mitral) valve

It joins the left atrium to the left ventricle . It has the same general structure of the triscuspid valve, but unlike the latter it has only two cusps: - anterior or aortic cusp - posterior cusp (or small cusp) → is quadrangular and smaller than the anterior cusp. Furthermore: - each flap has an axial and parietal face - papillary muscles are inserted on the free … Continue reading Bicuspid (or mitral) valve »