Cardiac muscle the walls of a house contain electrical wires and plumbing, cardiac muscle also contains specialised cells for conducting electrical signals rapidly (the cardiac conduction system), and blood vessels to bring nutrients to the muscle cells and take away waste products (the coronary arteries, veins and capillary network). Cardiac muscle cells or cardiomyocytes are the contracting cells which allow the heart to pump. Each cardiomyocyte needs to contract in coordination with its neighbouring cells to efficiently pump blood from the heart, and if this coordination breaks down then – despite individual cells contracting – the heart may not pump at all,
Coronary arteries Coronary arteries The coronary arteries are the arteries of the coronary circulation, which transports blood into and out of the cardiac muscle. They are mainly composed of the left and right coronary arteries, both of which give off branches. Coronary arteries can also be categorized as Epicardial (above the epicardium) and Microvascular (close to the endocardium). The left coronary artery arises from the aorta above the left cusp of the aortic valve and feeds blood to the left side of the heart. It branches into two arteries and sometimes a third branch is formed at the fork, known as a