Artificial pacemaker

This article is about a medical device which electrically stimulates the heart. For a similar device that stimulates the brain, see brain pacemaker.

Advancements in pacemaker function

When first invented, pacemakers controlled only the rate at which the heart's two largest chambers, the ventricles, beat.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Many advancements have been made to enhance the control of the pacemaker once implanted. Many of these enhancements have been made possible by the transition to microprocessor controlled pacemakers. Pacemakers that control not only the ventricles but the atria as well have become common. Pacemakers that control both the atria and ventricles are called dual-chamber pacemakers. Timing the contractions of the atria to precede that of the ventricles improves the pumping efficiency of the heart and can be useful in congestive heart failure.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Rate responsive pacing allows the device to sense the physical activity of the patient and respond appropriately by increasing or decreasing the base pacing rate via rate response algorithms.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Another advancement in pacemaker technology is left ventricular pacing. A pacemaker wire is placed on the outer surface of the left ventricle, with the goal of more physiological pacing than what is available in standard pacemakers. This extra wire is implanted to improve symptoms in patients with severe heart failure.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~