The Artificial Pacemaker 1958 – A Miracle That Regulates the Heartbeat

An artificial pacemaker is a device that uses electrical impulses to maintain a normal heartbeat. A healthy heart has its own electrical system to control its rhythms. With each heartbeat, an electrical signal spreads from the top of the heart to the bottom, causing the heart to contract and pump blood. This signal starts in a group of cells called the sinoatrial node, located in the heart's right atrium (upper chamber). Problems in the electrical signaling system can cause the heart to beat too fast (tachycardia), too slowly (bradycardia), or irregularly.

The artificial pacemaker has evolved from a large, cumbersome machine into a small modern device implanted in the body and powered by long-lasting batteries. 

• In 1952, American cardiologist Paul Zoll developed an external pacemaker that delivered painful electrical stimulation to the surface of the chest. 
• In 1958, inventors such as American Wilson Greatbatch and Swede Rune Elmqvist developed an implantable pacemaker using transistors. Electrodes placed in the heart's walls made it possible to produce lower-voltage, battery-powered units.
• By the mid-1960s, electrode systems could be passed through blood vessels into the heart and positioned within a heart chamber. 
• In the 1970s, lithium batteries and low-power circuits made it possible to develop units that could function for many years.

Today, in a dual-chamber pacemaker, one lead (wire) controls the atrium while the other controls the ventricle (lower chamber). In dynamic pacemakers, the frequency can change automatically according to need (for example, when significant body movements or changes in body temperature or dissolved oxygen levels are detected). Pacemakers can also monitor and store information about the heart's activity. Specialists can access this information during an examination.

Historical Figures Mentioned in This Article: Rune Elmqvist (1906–1996), Paul Maurice Zoll (1911–1999), Wilson Greatbatch (1919–2011)

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