The heart is a fist-sized muscular organ located in the center of your chest, slightly behind and to the left of the breastbone. It is divided into four main chambers:
A natural "pacemaker" called the sinoatrial (SA) node sends electrical impulses that tell the heart muscles when to contract. 📊 Heart Rate: The Vital Metric All About Heart Rate | American Heart Association Heart.rar
Receives oxygen-rich blood from the lungs and pumps it out to the rest of the body. The heart is a fist-sized muscular organ located
The right and left atria receive incoming blood. Heart.rar