Pacemakers: a short history
Tens of thousands of people have their lives improved with a heart pacemaker. Since the first pacemakers were implanted more than fifty years ago designs have improved so that pacemakers can adjust their pacing rate automatically and battery life gives years between operations for battery replacement. Now there is the prospect of pill-sized pacemakers powered by external wi-fi signals and heart-repair with engineered heart cells, removing the need for the current bulky technology. All these improvements require animal testing.
A very short history of pacemakers
This is a very short history of pacemakers finishing with the bioengineering that could replace them. Early research on dogs showed the heart could be regulated with external electrical stimulation. Many years later the invention of the transistor and the shrinking of other components led to a portable pacemaker and later a pacemaker that could be placed within the body. These were and are tested on animals such as the guinea-pig and pig. The next step in pacemaker technology may be a pill-sized 'wifi' pacemaker inserted into the heart that is powered by an external energy source. Eventually pacemakers may be replaced by biological heart repair, a technology currently being studied in zebrafish.