Pacemakers work to regulate heart rate by administering a slight electric shock and stimulating contraction of the heart muscle. The pacemaker must be surgically implanted and occasionally serviced to remain in working order, according to the National Heart, Lung, and Blood Institute.
The design of a pacemaker varies by manufacturer, but all have the same basic components. These consist of a battery to store the charge, a generator and wires with electrical sensors at their tips, according to the National Heart, Lung, and Blood Institute. The pacemaker's sensors pick up the electrical activity in the heart as it beats and relay that information to the computerized generator in the main body of the unit. If the patient's heart rhythm becomes abnormal, the generator administers shocks to put the heart back onto a stable rhythm.
Some pacemaker models are able to do more than monitor and regulate heart rate. Newer models also collect useful information about the patient's health, including blood temperature and respiration rate. Sophisticated pacemakers can be programmed to automatically detect an increase in physical activity and escalate the heart rate to compensate for the increased demands of exercise. Most pacemakers can be programmed remotely without directly accessing the on-board computer, explains the National Heart, Lung, and Blood Institute.