Dissection of “Right trigone of the heart”. The fibrous skeleton of the heart and right trigone is those tissues at the base of the heart which consists of dense collagen fibers which remain stationary with respect to functionally moving parts of the heart namely myocardium, valve leaflets and elastically distensible arteries arising from the heart. So far no clear guidelines are available for dissecting the fibrous skeleton of the heart and right trigone of the heart. The present study evolves the steps in dissecting the fibrous skeleton and right trigone of the cadaveric hearts. Its morphological features such as position, shape and extent are noted. Aim of the study is to dissect the right trigone of the heart and explain its dissection steps and morphology. Right trigone of the heart is situated at the base of the heart where four functional apertures of the ventricles are crowded together, which appears as figure of 8. In the central portion of the figure 8 right trigone of the heart is situated. The atrioventricular conducting bundle is only physiological connection between the atria and ventricle across the fibrous ring. The right and left trigone were dissected and observed. It feels cartilaginous and also called as key stone of the heart. It is triangular in shape and shoes extensions membranous septum, tendon of todaro, anterior fila coronaria of the right atrioventricular annulus. When it is viewed from superior aspect it looks like as head of the cow. Right trigone of the heart & its three dimensional views are helpful for both undergraduate and post graduate students of anatomy and cardiology. It would also help cardio-thoracic surgeons in Annuloplasty operations.

Keywords: Right Trigone of the Heart; Key Stone; Left Trigone; Conus Ligament; Annuli.