The Pacemaker, Your Heart, and our Body’s Electricity

March 14, 2022                                                                                                                                            Home

Electricity is everywhere, even in our bodies.  We usually think of electricity as a current going from one point to another point, such as from an outlet in the wall to an appliance, like a popcorn maker or to a light bulb.  The current travels through a wire or cable.

The body also has electricity, electricity needed for the nervous system to function.   These electric signals make it possible for us to move, think, and feel.  The signals are carried in the cells of our bodies.  The human body at rest can produce about 100 watts of power, enough to power a light bulb.  If we are very active, such as running as fast we can in a sprint, the body can then produce over 1,000 watts of power.

Most of us have directly experienced our body’s electricity, for example, when we touch a car door and get a small shock.  This is called a static shock and happens when there is a difference in electrical charge between your body and the surface you touch.  Another example is rubbing a balloon against a wall.  It will stick to the wall because it is attracted to the positively charged particles in the wall.

Diagram of human heart

The heart has its own electrical system, which is directly connected to the brain through  the body’s central nervous system.  The heart’s electrical system does two jobs: controling the heart rate (normally 60 to 100 beats per minutes) and keeping the blood pumping properly through the four chambers of the heart.  When there is a problem with either of these, it may be time for an pacemaker.

You may not know that the heart has its own pacemaker.  Located at the top of the heart, there is  group of cells that sends out an electrical impulse that causes muscle cells in the heart to contract the two upper heart chambers.  This contraction pumps blood down into the two lower heart chambers.  

Then another group of cells in the right upper chamber slows down the electrical signal.  This gives the lower chambers time to receive blood from the upper chambers.  Then these cells give a signal which causes the lower chambers to contract, causing the right chamber pumping blood to the lungs and the left chamber pumping blood to the rest of your body. 

After this process is completed, each part of the system electrically resets itself; and the pumping begins again. Whenever there is a problem – either in the heart muscle itself or in the flow of blood that the heart is pumping (such as a blood vessel blockage or leaking valve), your natural pacemaker (SA node) can no longer do its job.  Your doctor might install a battery-powered pacemaker to control – either temporarily or permanently – the electrical rhythms of the heart, rhythms which are essential to our lives.

In the course of the day, we rarely think about electricity in our homes and places of work.  Even less do we appreciate the wonders of electricity in our body and how it makes us “tick”.

Everyone needs to learn more about our electric cooperative.  For more information, go to

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