The heart has four chambers. The two upper chambers
are called atria
(the right atrium and the left atrium), and the two lower chambers are called
the heartbeat starts in the right atrium in a group of
special heart cells called the sinoatrial (or sinus) node. These cells act as a
pacemaker for the heart.
The heart's pacemaker sends out an electrical signal
spreads throughout the heart along electrical pathways. These pathways transmit
the signal from the upper to the lower chambers of the heart, which causes the
heart muscle to contract. Regular, rhythmic electrical signals keep the heart
pumping blood to the lungs and the body.
ByHealthwise Staff Primary Medical ReviewerE. Gregory
Thompson, MD - Internal Medicine Martin J. Gabica,
MD - Family Medicine Specialist Medical ReviewerRakesh K. Pai, MD, FACC - Cardiology, Electrophysiology
E. Gregory Thompson, MD - Internal Medicine
& Martin J. Gabica, MD - Family Medicine &
Rakesh K. Pai, MD, FACC - Cardiology, Electrophysiology
This information does not replace the advice of a doctor.
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