The human heart is controlled by its own bioelectrical triggering system. The heart, being a muscle in our body, has an electrical system which is responsible for causing it to contract and relax. Each heartbeat is initially stimulated by a network of cells called the SA node, located in the upper right chamber of the heart. This functions as the natural pacemaker of the heart. The impulse then travels through the AV node, which separates the top and bottom chambers of the heart and acts as a gate-keeper. From here the impulse travels to the bundle of His which causes stimulation of the bottom right and left sections of the heart. The heart undergoes this major pumping action to supply the cells of the body with blood. A disturbance anywhere along this pathway can block the proper flow of blood in the body, and cause serious trouble . For instance, if the SA node sends impulses out too slowly, or the impulse is being blocked anywhere along the pathway, this calls for a newly developed technology called the "pacemaker."
Artificial pacemakers are electronic devices most typically used with patients suffering from a condition in which the heart beats too slowly - (bradyarrythmia or bradycardia). This is most commonly a result of deterioration in the heart's own pacing system in elderly patients, though high blood pressure , coronary artery disease and scarring from a heart attack can cause bradyarrhythmias. Pacemakers are designed to maintain a normal heart rate, so that sufficient supply of nutrients and oxygen will be delivered through the blood to the vital organs.
Early ideas and inventions of cardiac research led to the development of more complicated instruments and machines. The use of electricity for stimulation of the heart in the late eighteenth century stirred many ideas.