finger with blood drop


The circulatory system is the route by which the cells in your body get the oxygen and nutrients they need,...

Heart Anatomy

Your heart is located between your lungs in the middle of your chest, behind and slightly to the left of your breastbone. A double-layered membrane called the pericardium surrounds your heart like a sac. The heart weighs between 7 and 15 ounces (200 to 425 grams) and is a little larger than the size of your fist.

Anatomy of the Heart and Cardiovascular System

The heart and circulatory system make up your cardiovascular system. Your heart works as a pump that pushes blood to the organs, tissues, and cells of your body. Blood delivers oxygen and nutrients to every cell and removes the carbon dioxide and waste products made by those cells.


A heartbeat is a two-part pumping action that takes about a second. As blood collects in the upper chambers (the...

Heart Valves

  Four valves regulate blood flow through your heart: •    The tricuspid valve regulates blood flow between the right...

Fetal Heart

The baby growing inside of the mother’s uterus (the womb) is called a fetus. The growing fetus is fully dependent...

coronary circulation

Coronary Arteries

Coronary Circulation The heart muscle, like every other organ or tissue in your body, needs oxygen-rich blood to survive. Blood...