Anatomycal and histological structure of aortic valve in Baikal seal

Abstract

This article studies peculiarities of the anatomical and histological structure of the aortic valve cusps in Baikal seal in the age of 3-3.5 years. Topographically, the aortic valve takes a central position and is located between the atrioventricular valves, and cranial - pulmonary valve. Projectively, the aortic valve is placed above the level of the atrioventricular valves, but below the level of the pulmonary valve. The aortic ostium has marked sinuses, two coronary and one septal, forming the aortic bulb. The valve is shown by the septal right and left semilunar cusps. The septal cusp is caudally attached to the aortic ostium and the right and left have a cranial location. Aortic valve cusps have three layers of connective tissue: fibrosa (aortic) – with collagen fibers, ventriculosa (ventricular) - with elastic and spongiosa (intermediate) - a combination of both fibers, give strength to this structure. The thickness of the ventricular layer of the cusp is 2.4 times higher than the thickness of the aortic layer. At the places of the greatest thickness value, there are transverse resections (2 deep and 4 surface), which increase the contact surface and increase the pressure on the cusp. The thinning area, which is located before the bulging edge of the cusp, acts as a closure point for the aortic valve cusps.