THORAX ABDOMEN AND PELVIS

Detailed explanation-1: -The pericardium is the outside layer that does not compose part of the heart. It houses fluid that reduces friction to the heart and protects it as it pumps.

Detailed explanation-2: -The epicardium constitutes the visceral pericardium, underlying fibro-elastic connective tissue, and adipose tissue. [2] Coronary arteries and veins, lymphatic vessels, and nerves run below the epicardium. The endocardium is composed of the endothelium and the subendothelial connective tissue layer.

Detailed explanation-3: -The epicardium, the outermost tissue layer that envelops all vertebrate hearts, plays a crucial role in cardiac development and regeneration and has been implicated in potential strategies for cardiac repair.