Today marks the 36th installment in a series of articles by titled Heroes of Progress. This bi-weekly column provides a short introduction to heroes who have made an extraordinary contribution to the well-being of humanity. You can find the 35th part of this series here.

This week, our hero is Wilson Greatbatch, the American engineer and inventor who created the first implantable pacemaker. The implanted pacemaker uses electrical pulses to ensure that the patient’s heart beats at a normal pace. The life expectancy for people with a pacemaker is the same as that for the general public and receiving a pacemaker is generally considered a low-risk operation. Every year, hundreds of thousands of people are implanted with a pacemaker and the World Economic Forum has estimated that since its invention, the pacemaker has already saved 8 million lives.

Wilson Greatbatch was born on September 6, 1919 in Buffalo, New York. Greatbatch’s father was an English carpenter who immigrated to the United States in the early 1900s. Greatbatch’s American mother died when the inventor was a young boy. From an early age, Greatbatch had an interest in electronic gadgetry and, as a teenager, he enjoyed assembling radios. After he finished high school in 1936, Greatbatch put his knowledge of electronics to use by joining the U.S. Navy as a wireless operator and repairer of electronic equipment.

Greatbatch served in both the Atlantic and Pacific during World War II, before being honorably discharged in 1945 as a chief aviation radioman. After spending a year working as a telephone repairman, Greatbatch enrolled at the University of Cornell to study electrical engineering. To supplement his income, Greatbatch ran the university’s radio transmitter. He also assisted with the electronics that ran the university’s radio telescope.

Greatbatch graduated from Cornell in 1950 with a B.E.E. and began studying for his MSc in electrical engineering at the University of Buffalo. In 1952, Greatbatch became an assistant professor at the University of Buffalo’s electrical engineering department.

In the early 1950s, Greatbatch first learned about heart block – a condition in which nerves fail to send electrical impulses to the heart, which then causes irregular heartbeats – when two surgeons visited Cornell University. At the time, the medical procedure to combat heart block was done through painful electric shocks delivered via bulky external equipment. Intrigued, Greatbatch started to ponder a way to create a smaller, implantable device to help the heart beat regularly.

In 1956, while still working as an assistant professor in Buffalo, Greatbatch made the most important discovery of his lifetime – all thanks to a fortuitous error.

While creating an instrument that Greatbatch hoped could record heartbeats, he accidentally soldered a wrong-sized resistor into the circuit. Rather than simply recording electrical pulses that could be used to monitor heartbeats, Greatbatch’s mistake caused the device to generate regular pulses of electrical current. Having realized that he had found a way to both electrically simulate and stimulate a heartbeat, Greatbatch later recalled that he “just stared at the thing in disbelief, thinking this was exactly the properties of a pacemaker.”

Over the next two years, Greatbatch was successful in miniaturizing the device down to just two cubic inches. After encasing the pacemaker in an epoxy resin to protect it from bodily fluids, he was keen to test it. Thanks to the help of William Chardack, a surgeon at Buffalo’s veterinary hospital, the pacemaker, powered by a mercury-zinc battery, was successfully implanted into a dog in May 1958. With this experiment, Greatbatch was able to demonstrate that his device could control the dog’s heartbeat.

Later that year, with $2,000 in savings (approximately $17,500 in today’s money), Greatbatch left his job at Buffalo University and further developed his invention in his garden shed. By 1960, Greatbatch’s pacemaker was successfully implanted in the first human patient – a 77-year-old man who went on to live another 18 months. In the same year, nine more patients received the implant.

Greatbatch patented his pacemaker in 1962 and licensed his invention to Medtronic Inc., a leading manufacturer of medical equipment. However, Greatbatch soon realized that because his pacemakers could only last two years due to battery constraints, a more reliable source of power was needed in order to make his pacemaker a long-term success. In the late 1960s, Greatbatch acquired the rights to a newly developed lithium iodine battery, which could make the pacemaker last more than ten years. The lithium iodine battery is still used in pacemakers today.

In 1970, Greatbatch founded Wilson Greatbatch Ltd (now Greatbatch Inc). By 1972, Greatbatch’s new pacemakers that could last more than ten years were on the market and being implanted in thousands of patients across the world. Today, Greatbatch Inc is a world-leading battery supplier for the medical device industry and the largest producer of pacemakers in the United States.

Throughout his life, Greatbatch received numerous honors. He was given four honorary doctorates and, in 1988, he was inducted into the National Inventors Hall of Fame. In 1990, he was awarded the Lemelson-MIT Lifetime Achievement Award. In 2001, he was granted the highest honor from the National Academy of Engineering, which he shared with Earl Bakken, who invented the external pacemaker. In 1983, Greatbatch’s implantable pacemaker was also recognized as one of the two major engineering contributions to society of the previous 50 years by the National Society of Professional Engineers.

Later in life, Greatbatch and his wife established the Eleanor and Wilson Greatbatch Foundation, which focused on donating money to schools and other educational causes. Greatbatch passed away on September 27, 2011 in Williamsville, New York. At the time of his death, he held over 220 patents. Even late in life, he remained interested in researching everything from nuclear-powered spaceships to solar-powered canoes.

Thanks to the work of Wilson Greatbatch, millions of people around the world have been saved from a painful early death. Every year, hundreds of thousands of people continue to have their lives saved thanks to the implantable pacemaker. For these reasons, Wilson Greatbatch is our 36th Hero of Progress.