Structures to know: Heart

Epicardium

The outer layer of the heart wall.

Myocardium

The muscular middle layer of the heart wall responsible for contraction.

Endocardium

The inner lining of the heart.

Apex of the Heart

The tip or point of the heart, pointing downwards and to the left.

Base of the Heart

The broader upper portion of the heart where major blood vessels enter and exit.

Aorta

The main artery that carries blood away from the heart to the rest of the body.

Pulmonary Trunk

The artery that carries deoxygenated blood from the right ventricle to the lungs.

Superior vena cava

The large vein that carries deoxygenated blood from the upper body to the right atrium.

Inferior vena cava

The large vein that carries deoxygenated blood from the lower body to the right atrium.

Right coronary artery

The artery that supplies blood to the right side of the heart.

Left coronary artery

The artery that supplies blood to the left side of the heart.

Coronary sinus

A large vein that collects deoxygenated blood from the heart muscle.

Right Atria

The right upper chamber of the heart that receives deoxygenated blood.

Right Ventricle

The right lower chamber of the heart that pumps deoxygenated blood to the lungs.

Left Atria

The left upper chamber of the heart that receives oxygenated blood from the lungs.

Left Ventricle

The left lower chamber of the heart that pumps oxygenated blood to the body.

Interatrial septum

The wall of tissue that separates the right and left atria.

Interventricular septum

The wall of tissue that separates the right and left ventricles.

Right atrioventricular (AV) valve

Valves that separate the right atrium and right ventricle, also called the tricuspid valve.

Chordae tendineae

Tendon-like cords that connect the heart valves to the papillary muscles.

Papillary muscles

Muscles located in the ventricles of the heart that are attached to the chordae tendineae and help control the valves.

Pulmonary valve

The valve that prevents backflow of blood from the pulmonary artery into the right ventricle.

Left atrioventricular (AV) valve

Also known as the mitral valve, it separates the left atrium and left ventricle.

Aortic valve

The valve that prevents backflow of blood from the aorta into the left ventricle.

Sinoatrial node

The heart's natural pacemaker located in the right atrium.

Atrioventricular node

A cluster of cells that receive electrical impulses from the sinoatrial node.

Atrioventricular bundle

Also known as the bundle of His, it conducts impulses from the AV node to the ventricles.

Bundle branches

Branches of the AV bundle that spread throughout the ventricles.

Purkinje Fibers

Fibers that carry the impulse to the heart muscle to stimulate contraction.