Role of pacemakers in atrial fibrillation
Pacemakers are devices with electronic circuitry which can give electrical pulses to the heart which has a defective natural pacemaker. Natural pacemaker of the heart is a group of cells situated in the upper right chamber of the heart known as sinus node. Sometimes a pacemaker is needed when the pulses of the sinus node are not conducted well to the lower chambers of the heart (ventricles), in a condition known as complete heart block. In addition to this role of pacemakers in atrial fibrillation is widening.
Atrial fibrillation is an electrical disorder of the upper chambers of the heart in which regular electrical pulses from the sinus node are replaced by fast disorganized electrical activity which causes the upper chambers (atrial) to stand still and quiver. This can lead to blood clot formation in these chambers which can move along the blood vessels to regions like the brain and cause disorders like stroke or paralysis.
There could be more than one role of pacemakers in atrial fibrillation. In those with recurrent rather than persistent atrial fibrillation, pacing the atrium (upper chamber of the heart) simultaneously from multiple sites can reduce the recurrence of atrial fibrillation. Another role is to have a pacemaker when atrial fibrillation is refractory. In drug refractory atrial fibrillation, radiofrequency current is used to cut off the pathways which conduct the atrial pulses to ventricles using specially designed electrode catheters. This produces a complete heart block and requires a pacemaker to give regular electrical pulses for the ventricles to contract regularly.