Pacemaker Of The Heart: An Accidental Invention

What is a pacemaker?

A pacemaker is an electronic device that is implanted in the body to regulate heart rate and rhythm. In situations where the heart is not beating normally, it stimulates the heart electrically. It is powered by batteries and is connected to the heart by a long, thin wire. It is also referred to as a cardiac pacemaker or an artificial pacemaker.

Pacemaker: History Timeline

The First Cardiac Pacemaker

John Hopps, a Canadian electrical engineer who was studying the effects of radio frequency heating on hypothermia in 1941, created the first cardiac pacemaker. He discovered that if the heart stopped beating when the body's temperature dropped, it could be artificially restarted by stimulating it mechanically or electrically. The first cardiac defibrillation device was created as a result of this research, and Hopps used it in 1949 to restart the heart of a dog.

Hopps created the first pacemaker in 1950 using research on dogs, but it was too big to be used internally.

Implantable Pacemaker

The first implantable pacemaker was created by Dr Rune Elmqvist, a physician who was also an engineer for a Swedish company. The device was created by Dr Elmqvist in collaboration with Ake Senning, a senior physician and cardiac surgeon at the Karolinska Institute Hospital in Solna, a town close to Stockholm.

Arne Larsson, their first patient, had his first pacemaker implanted in secret on October 8, 1958, right in the middle of his life. His wife, Else-Marie persuaded the scientists to perform the surgery, though they strongly refused initially. Finally, it was a prank made under the influence of female power and was officially unacceptable! Arne Larsson later underwent more than 20 pacemaker implantations over the course of 43 years.

The first wearable pacemaker with a battery was created in 1957 by electrical engineer Earl E. Bakken, who co-founded "Medtronic," an American medical device company.

In 1958, the device was introduced into clinical practice by renowned physician C Walton Lillehei of the University of Minnesota, also known as "the father of open chest surgery." This pacemaker (created in 1958) later went by the name Medtronic Cardiac Pacemaker 5800 or Medtronic Pacemaker. With the introduction of the Model 5800, Medtronic Inc. eventually rose to the position of being the leading cardiac pacemaker manufacturer in the world.

In 1958, Mr Wilson Greatbatch was working on recording tachycardias at roughly the same time. He understood that the implantable pacemaker of the heart could be driven by the low-level electrical current that would also drive a human heart. Mr Greatbatch requested that a mercury battery-powered implantable pacemaker be tested in the hospital's animal lab by surgeon Dr Andrew Gage and chief of surgery Dr William Chardack. It was demonstrated that the design was effective. They collaborated to implant an electrode and pulse generator in a dog.

They spent the next two years perfecting their design for an implantable device that would keep the same pulse rhythm for extended periods of time.

In 1960, Dr Chardack implanted the device successfully in a 77-year-old man; the patient survived for two years before passing away from unrelated causes. Later, the Chardack-Greatbatch pacemaker was owned by Medtronic Inc. Greatbatch also developed the lithium battery for pacemakers and established Wilson Greatbatch Ltd. to manufacture them. Modern pacemakers have batteries that can operate continuously for 10 to 12 years.

John Hopps had a pacemaker implanted in 1984 to control his own heartbeat, and he got a new pacemaker 13 years later. By the mid-80, fitting cardiac pacemakers had become a routine procedure that saved thousands of lives.

The first commercially manufactured implanted pacemaker was created by Chardack and Greatbatch. With this invention, many patients with irregular heartbeats are spared potentially fatal complications.

Today, more than 3 million people worldwide have been implanted with cardiac pacemakers.

How Does A Pacemaker Work?

Pacemakers only function when they are required. The pacemaker communicates with your heart through electrical signals to adjust the beat if it beats too slowly, a condition known as bradycardia. Some more recent pacemakers also have sensors that notice changes in breathing or body motion and send out signals to the devices to raise the heart rate during exercise as necessary.

Natural Pacemaker Of The Heart

The sinus node (or SA node) is known as the natural pacemaker of the heart.

SA Node Function: The sinoatrial node generates the electrical impulses that spread out through the upper chambers of the heart, namely the left atrium and the right atrium. Thereby, it sets the normal rhythm and rate of a healthy heart. So, the pacemaker functions as the SA node of the heart.