Britannica Educational Publishing 
Cardiovascular System 

Though only about the size of a clenched fist, the human heart bears the immense burden of sustaining human life and activity. Functioning to circulate blood throughout the body, the heart is an organ on which all others intimately depend. This volume relates the anatomy of the heart and the effects of the diseases to which it is sometimes prone. Annotated diagrams and illustrations bolster the narrative and highlight significant aspects of cardiology and the incredible cardiovascular system.