A<unk>  is one or more types of cellular components that, when "implanted or injected into certain regions of the heart," produce specific electrical stimuli that mimic that of the body's natural pacemaker cells.<unk> s are indicated for issues such as heart block, slow heart rate, and asynchronous heart ventricle contractions. The<unk>  is intended as an alternative to the artificial cardiac pacemaker that has been in human use since the late 1950s. Despite their success, several limitations and problems with artificial pacemakers have emerged during the past decades such as electrode fracture or damage to insulation, infection, re-operations for battery exchange, and venous thrombosis. The need for an alternative is most obvious in children, including premature newborn babies, where size mismatch and the fact that pacemaker leads do not grow with children are a problem. A more<unk>  approach has been taken in order to mitigate many of these issues. However, the implanted<unk>  cells still typically need to be supplemented with an artificial pacemaker while the cells form the necessary electrical connections with cardiac tissue.
Biological pacemaker
Cardiac pacemaker
Artificial cardiac pacemaker
Ventricular assist device
Antiarrhythmic agent
Artificial heart valve
Pacing 
Artificial heart