The Study Of The Morphology Of The Fibrous Skeleton Of Heart And The Related Tissues In Sheep

This study was designed to illustrate the fibrous skeleton of heart and the related structures in sheep. Hearts from 30 Dorper sheep aged 10-12 month from Ru-yang and Yi-chuan of Henan province with carotid artery bleeding to death. These hearts were examined with the B-type ultrasonic and X-ray to observe whether the osseous tissue existed in the cardiac fibrous scaffolds or not after the pericardia was removed. And then the aorta, pulmonary artery, precaval vein, postcaval vein, left atrium, right atrium, left atrioventricular orifice and right atrioventricular orifice were filled with the degreasing cotton, and then were fixed with the 10% formalin solution. The fibrous skeleton of heart was stripped out after the heart was fixed completely. In order to determine the size of the cardiac fibrous scaffolds, we got the measures of the perimeter of aortic annulus, pulmonary annulus, mitral annulus and tricuspid annulus respectively; and the three sides length of the left and right fibrous triangle by the vernier caliper respectively. And then selected the cardiac fibrous scaffolds and the tissues around were examined by the conventional paraffin section. Using hematoxylin-eosin(HE) staining, Masson trichrome(Masson) staining, Verhoeff staining and Van Gieson(VG) staining to observing the histological structure of the fibrous skeleton of heart and the tissues around it. The results of this study were as follows:1. The anatomic localization of fibrous skeleton of heart in sheep:The fibrous skeleton of heart was the attachment of the atrial muscle, ventricular muscle and heart valve. The results showed that:The fibrous skeleton of heart in sheep included the annulus of pulmonary artery, the aorta annulus, the mitral valve annulus and the tricuspid valve annulus, the left fibrous trigone, the right fibrous trigone and the cone ligaments between the pulmonary artery and aorta annulus. The color was porcelain, and it was a bit hard to touching. The three pulmonary artery annulus was an arc closed loop has three peaks and surrounded by the pulmonary semilunar valve attachment, and three peaks were respectively semilunar triangle peaks between the two leaves. Aortic annulus is similar to the pulmonary artery annulus, consisting of three and a half months of the aortic valve attachment, Mitral valve annulus was made up of cleft anterior leaflet and after mitral valve and joint disc valves attachments, most of the annulus was the adhesion of the left atrium muscle and the left ventricular muscle, another part of the main artery of non-coronary artery flap attached down, and straight before the mitral valve disc, constituted a part of the left ventricular outflow tract; Tricuspid annulus was composed of the attachments of the anterior valve and posterior valve and the diaphragm valve, and was the attachment of the right ventricle muscle and right atrium muscle; The left fibrous trigone was located at the bottom of the left coronary artery branches of the aorta, respectively surrounded by the aortic root, mitral valve annulus and the coronary groove; The right fibrous trigone was located at the bottom of the aorta and the outer side of the non-coronary artery valve, was in the endocardial lower area among the diaphragm valve of the tricuspid valve, the aortic root, and the anterior margin of the coronary sinus, usually the fiber right triangle vertex followed the aortic root extension forward, its shape was irregular, and similar to the triangle, so the name center fiber body, was the most hard part of the whole heart.2. The measurement results of the fibrous skeleton of heart in sheep:The average perimeter of the aortic annulus were 4.899±0.870 cm, the average perimeter of pulmonary arterial annulus were 4.160±1.075 cm, the average perimeter of the mitral annulus were 7.842±0.887 cm, the average perimeter of the tricuspid annulus was 7.968±1.153 cm; the three sides of the left fibrous trigone trilateration were:0.587±0.172 cm,0.593±0.154 cm,0.643±0.104 cm; and the three sides of right fibrous trigone were:0.738±0.132 cm,1.382±0.374 cm, 1.683±0.317 cm.3. The histological observation of the fibrous skeleton of heart in sheep:the staining of mitral annulus, tricuspid annulus and pulmonary artery annulus were similar to each other. The main component of mitral valve, tricuspid valve and pulmonary semilunar valves are collagen fibers, which was wavy and parallel arrangement. And there was no no blood vessels exist. The main component of the chordae tendineae of mitral annulus and tricuspid annulus are dense collagen fibers, which was also wavy and parallel arrangement; Staining of aortic annulus and fiber triangle:the surface of the aortic semilunar valve and the left fibrous trigone are more dense collagen fibers, collagen fiber of the aortic semilunar valve’s valvular are distributed loose; The right fibrous triangle contained three layers:the outermost layer was collagen fiber layer which was wavy and parallel arrangement, middle layer was cartilage tissue, inner layer was a mature bone plate and marrow tissue.4. The observation of the bone in fibrous skeleton of heart in sheep by X-ray:In one of ventricular septal incision heart of sheep, observed a typical high bone shadow, through further the anatomy analysis, it was in the central fibrous body(right fibrous trigone) of heart in sheep.5. The observation of the bone in fibrous skeleton of heart in sheep by the B-type ultrasonic:Using B-type ultrasonic to observing the heart of sheep with the ultrasound probe parallel and perpendicular to the coronary groove on the left border of the heart. All of the hearts of sheep were observed a strong echo band of typical bone.The experiments on the morphology of the fibrous skeleton of heart and the related tissues in Sheep had been studied using veterinary imaging, anatomy and histology observation, and for the first time the size of the cardiac fibrous scaffolds were measured and observed histologically, for the first time discovered the existence of bone marrow in the heart bone. The result of the morphology of the fibrous skeleton of heart and the related tissues in Sheep would fill the gaps in this data, and added more content for the anatomy and comparative anatomy.