GROSS 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: -Cardiac muscle (or myocardium) makes up the thick middle layer of the heart. It is one of three types of muscle in the body, along with skeletal and smooth muscle. The myocardium is surrounded by a thin outer layer called the epicardium (AKA visceral pericardium) and an inner endocardium.

Detailed explanation-3: -Cardiac muscle tissue, or myocardium, is a specialized type of muscle tissue that forms the heart. This muscle tissue, which contracts and releases involuntarily, is responsible for keeping the heart pumping blood around the body.

Detailed explanation-4: -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.