Valvular Morphology and Morphometry of the Tricuspid Valves in Sheep and Goat

Abstract

The tricuspid valve was the largest of all cardiac valves in both sheep and goat. The fibrous ring that formed the annulus of the right atrio-ventricular orifice was nearly elliptical in sheep but circular in goat.  The annulus helped in the attachment of all the three leaflets viz., anterior, posterior and septal leaflets of the tricuspid valve. These leaflets were roughly triangular in shape and has commissure in between them. The largest leaflet was the anterior leaflet as in humans and the smallest was the septal leaflet in both species. The free edge mean length of posterior and septal leaflets, mean depth of all the three leaflets and the mean height of the anterio-septal and septo-posterior commissures were significantly higher in goat. The mean thickness of all the three leaflets was similar in both the species. Histomorphological features of the tricuspid valve were similar in sheep and goat. Histochemical reactions for carbohydrates were positive for Periodic acid schiff and Alcian blue in the connective tissue layers. Alkaline phosphatase activity was weak. The reaction for lipids was negative for Oil red O and cholesterol activity. The endothelial linings of the valve were moderate for Succinic dehydrogenase activity in both species. These anatomical similarities of tricuspid valve in goat may help understand the valvular pathologies of tricuspid valve regurgitation (TR) and stenosis (TS), for their clinical diagnosis and therapeutic intervention in humans.