Pacemakers and implantable cardioverter defibrillator (ICDs) are devices that regulate irregular heartbeats through implanted devices located in the chests of affected patients. The devices use electrical signals to regulate heartbeats too fast and too slow, based on the arrhythmia.
The devices are suggested for patients at risk for potentially fatal arrhythmias.
A pacemaker sends electrical signals to start or regulate slow heartbeats. A small device placed under the skin may be used as a permanent replacement to the heart's pacemaker, the SA node, if the heart can't function normally and has developed a permanent slow rhythm.
An ICD is similar to a pacemaker but larger. An ICD delivers two different levels of electrical shock — a low level to convert an abnormal rhythm back to normal and a high level if the arrhythmia is incredibly severe.
The device can sense when a heart is beating too fast or too slow, delivering a proper shock to regulate the abnormal rhythm.