Mitral Orifice

Mitral orifice

The mitral valve or mitral atriogastric orifice is a bicuspid valve of two leaflet muscles located in the right (less often in the left) atrium between the mouth of the vena cava and the sinus of Valsalva. The mitral valve consists of anterior and posterior leaflets and tendon threads to which the leaflet muscles are attached. The anterior leaflets consist of triangular muscle fibers, they are directed into the atrium cavity, and the posterior leaflets are less developed and directed towards the interatrial septum. The space between the valves is free; during the contraction of the heart, they form the atrio-gastric opening, which ensures uninterrupted blood circulation. The valve muscles receive innervation from the right sympathetic cervical ganglion. They are located next to the valves of the aorta, pulmonary artery and vein. The interconnection of the valves is carried out through the valves and tendon threads, which are located on the chords. In total, there are from 12 to 18 chordal filaments located around the pharynx. The normal functioning of the mitral orifice contributes to the enrichment of the blood with carbon dioxide and other components passing through the left atrium.

Structure and functioning

If we consider the normal operation of the mitral atrioventricular valve, then it functions synchronously with other systems of the left ventricle. During the cardiac cycle, the atrium contracts towards the stomach. During systole, the volume of the atrium cavity increases. The pressure in the LV cavity decreases, and the semilunar valves close, thereby preventing arterial blood from leaking through the right atrium into the veins. When does the atrium begin

** 63: Human Embryology: Mitral (atrioventricular) valve and its function** The mitral orifice is one of four oval openings in the interatrial septum. It connects the right atrium to the left atrium. This opening is also known as the atrioventricular orifice, and the opening is called the mitral orifice. On average 2