Many of you would have heard about pacemaker, a small device powered by a small battery, can regulate your heart beat. It consists of two parts – a generator and wires. I have also heard about it many times but never tried to know its functions. I only know that pacemaker is used to control heartbeats. So today I decided to know its functions.
How pacemaker regulates your heartbeats
Your heart has natural pacemaker which generates the electrical impulses that help your heart to beat. This natural pacemaker is called the sinoatrial node or sinus node which is made of specialized cells that generates the electrical impulses in heart muscles. It is found in the top of the right atrium (upper chamber of the heart).
Heart chambers contracts properly when electrical impulses produced by sinus node moves from upper chambers to lower chambers (ventricles) of the heart. Heart can’t beat without these signals, so these impulses must convey from right atrium to the ventricles.
When natural pacemaker stopped working properly or electrical pathways of your heart get blocked, your heart rhythm becomes irregular. That means your heart may pump too slow or too fast.
In this condition artificial pacemaker is placed in your heart so that electrical impulses could be produced to help it beats properly. A conductor (electrode) is sited near the heart wall so that electrical impulses could be easily send to the heart.
According to requirement, pacemaker stops or starts sending electrical impulses to the heart when its rhythm goes above or down a certain level. Most pacemakers have a sensing mode feature which makes them understand whether the supply of electrical impulses should be stopped. These are named demand pacemakers.
Source: http://www.heart.org/HEARTORG/Conditions/Arrhythmia/PreventionTreatmentofArrhythmia/Pacemaker_UCM_448480_Article.jsp#.W0isfTl9jIU