Pre-Med Heart Vocab

Atria

The two top chambers of the heart that receive blood and pass it to the ventricles.

Ventricles

The two bottom chambers that pump blood out of the heart to the lungs and the body.

Myocardium

The thick muscle layer of the heart that contracts to pump blood.

Endocardium

The smooth inner lining of the heart that helps blood flow easily.

Epicardium

The outer layer of the heart that protects it and contains blood vessels.

Pericardium

A protective sac around the heart that reduces friction and prevents overstretching.

Cardiac valves

One-way doors in the heart that keep blood moving in the right direction.

Tricuspid valve

Valve between the right atrium and right ventricle that prevents backflow.

Mitral (bicuspid) valve

Valve between the left atrium and left ventricle that prevents backflow.

Aortic valve

Valve that lets oxygenated blood leave the heart to go to the body.

Pulmonary valve

Valve that sends deoxygenated blood to the lungs.

Coronary arteries

Blood vessels that supply oxygen to the heart muscle itself.

Cardiac conduction system

The heart’s electrical system that controls heartbeat timing.

Sinoatrial (SA) node

The heart’s natural pacemaker that starts each heartbeat.

Cardiac output

The amount of blood pumped per minute (\text{heart rate} \times \text{stroke volume}).