ANATOMY

Detailed explanation-1: -The muscle layer of the heart is termed the myocardium and is made up of cardiomyocytes. The myocardium is found in the walls of all four chambers of the heart, though it is thicker in the ventricles and thinner in the atria.

Detailed explanation-2: -The main function of the myocardium is to facilitate the contraction and relaxation of the heart walls in order to receive and pump the blood into the systemic circulation. In addition, the myocardial cells provide a scaffold for heart chambers and conduct electrical stimuli.

Detailed explanation-3: -The myocardium is mainly made up of two types of cells: cardiomyocytes and fibroblasts. Fibroblasts are distributed between cardiomyocytes, along with extracellular matrix (ECM), blood vessels, lymphatic vessels, and nerve endings.

Detailed explanation-4: -Three layers of tissue form the heart wall. 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-5: -Cardiac muscle, also called the myocardium, is one of three major categories of muscles found within the human body, along with smooth muscle and skeletal muscle. Cardiac muscle, like skeletal muscle, is made up of sarcomeres that allow for contractility.