Ok so here is it, the flow of blood through the heart. The electrical impulses originate in a small bundle of specialized cells called SA node (sinoatrial node) located in the right atrium. This is the heart’s natural pacemaker and this electrical activity spreads through the wall of the atria and causes them to contract.
The electrical activity then goes through the AV node (atrioventricular node) which slows the electrical signal before it enters the ventricles. This delay allows the atria time to contract before the ventricles contract.
The His-Purkinje network is a pathway of fibers that sends the impulse to the muscular walls to the ventricles causing them to contract.
At rest, a normal heart beats around 50 to 99 times per minute. Things such as exercise, emotions, fever and some medications can cause your heart to be faster which sometimes can be over 100 beats per minute.
In our next blog, we will talk about the circulatory system.