ANATOMY

Detailed explanation-1: -The outer layer of the heart wall is the epicardium, the middle layer is the myocardium, and the inner layer is the endocardium.

Detailed explanation-2: -Myocardium-the middle, muscular layer. Endocardium-the inner layer.

Detailed explanation-3: -The myocardium is the middle muscular layer of the heart. It is the thickest layer which lies between the single-cell endocardium layer, and the outer epicardium, which makes up the visceral pericardium that surrounds and protects the heart.

Detailed explanation-4: -Myocardium. The middle layer of the heart wall is the myocardium-the muscle tissue of the heart and the thickest layer of the heart wall. It is composed of cardiac muscle cells, or cardiomyocytes.