• Electrical current powers the human heart."Powerful" is Copyrighted by Flickr user: *** Fanch The System !!! *** (Fanch) under the Creative Commons Attribution license.
  
  

Parts of the Electrical System

• The electrical system of the heart comprises the sinoatrial (SA) node, the atrioventricalar (AV) node and the His-Purkinje system. The SA node is located in the right atrium and is composed of a cluster of specialized cells that are referred to as the heart's pacemaker. The AV node consists of a cluster of cells that reside in the center of the heart. The His-Purkinje system is a bundle of fibers in the interventricular septum and papillary muscles.
  
  

Contractions

• According to the Cleveland Clinic, the electrical impulses that kick-start the human heartbeat originates in the SA node. This impulse makes the walls of the atria contract. The His-Purkinje system sends impulses that cause the ventricular walls to contract. The AV node acts as a control center between the atria and ventricles of the heart. It creates the rhythmic slowing that allows the atria and ventricles to contract alternately.
  
  

Blood Flow

• The electrical system that supplies power to the atria and ventricles makes it possible for blood to be pumped through the heart. In "Health and Wellness," Gordon Edlin explains that heartbeats are actually created by the contractions that are created when blood flows through these ventricles. This delicate balance of perfectly timed fluid motions can be interrupted by certain heart conditions.
  
  

Irregular Heartbeats

• Irregular heartbeats, or arrhythmias, are caused by malfunctions in the heart's electrical system. EMedicineHealth.com explains that there are various types of arrhythmias that are classified according to origin. Some arrhythmias, such as sick sinus syndrome, originate in the SA node. Others begin in the atria, such as atrial fibrillation. Examples of arrhythmias that begin in the AV nodes are supraventricular tachycardia and atrial flutter.
  
  

Artificial Assistance

• A heartbeat that is compromised by a heart condition can typically be restored with the help of a pacemaker, an electrical device that operates on battery power. The pacemaker mimics the electrical impulses that are generated by the heart and sends those artificial impulses through an electrode placed at the wall of the heart.