Wilson Greatbatch, an electrical engineer who helped develop the first implantable pacemaker, a revolutionary device that since the 1960s has pumped life into millions of people, died Sept. 27 at a nursing home in Williamsville, N.Y. He was 92.

He had renal failure, said his daughter Anne Maciariello.

Mr. Greatbatch, an incurable tinkerer who constructed a radio transmitter at 16, held more than 300 patents, and his inventions largely shaped modern cardiology.

“He was one of the greatest American inventors of the 20th century,” Kirk Jeffrey, who wrote the 2001 book “Machines in our Hearts: The Cardiac Pacemaker, the Implantable Defibrillator and American Health Care,” said in an interview. “The work he did saved a great many lives.”

Beyond the implantable pacemaker, Mr. Greatbatch introduced the use of compact, long-lasting lithium batteries to the device. His company’s batteries at one time provided power to 90 percent of all pacemakers and were used by NASA to power equipment for space shuttle missions.

Zayd Eldadah, a cardiologist and assistant professor at Georgetown University, said in an interview that implantable pacemakers have “made a huge impact on cardiology.”

“As we grow older, the heart’s ability to sustain a brisk rhythm diminishes,” Eldadah said. “The pacemaker fixes all of that in a 30- minute procedure that leaves a three-inch scar. It’s been a revolutionary change for hundreds of thousands of people every year.”

The first pacemakers were built in the early 1950s. Some early designs were the size of a television and needed to be plugged into a wall socket. Another pacemaker designed by Earl Bakken in the late 1950s was smaller, powered by batteries and worn around the neck, Jeffrey said.

Mr. Greatbatch was an assistant professor of electrical engineering at the University of Buffalo when, in 1956, he accidentally devised what is considered one of medicine’s most significant achievements.

At the time, he was tasked with building equipment to monitor heart sounds when he placed the wrong transistor into the instrument. The transistor — 100 times more powerful than those he usually used — emitted an electrical pulse that mimicked the rhythm of the human heart. He immediately realized the device’s potential as a new kind of pacemaker. His idea was to use new transistor technology to make a pacemaker that could survive inside the patient’s body.

Working in his barn workshop, warmed by a wood-fire stove, Mr. Greatbatch spent two years developing his prototypes.

In 1958, he presented his devices to William Chardack, a surgeon at Buffalo’s Veterans Administration Hospital, and the two became collaborators.

That year, Mr. Greatbatch and Chardack wired a pacemaker composed of two Texas Instruments transistors to the heart of a dog. The device, which was slightly larger than a hockey puck and weighed half a pound, flawlessly controlled the animal’s heartbeat.

“I seriously doubt if anything I ever do will ever give me the elation I felt that day when my own two cubic inch piece of electronic design controlled a living heart,” Mr. Greatbatch wrote in a diary afterward.

Mr. Greatbatch and Chardack continued to experiment with the design to make it more efficient. One dog lived 104 days with one of the devices.

But the device had its flaws, Jeffrey said. Bodily fluids often permeated through the pacemaker’s protective casing and destroyed the electronics.

Despite their device’s imperfections, Mr. Greatbatch and Chardack began implanting the pacemakers into humans in 1960. Those considered for the surgery had only a 50 percent chance of surviving without intervention.

“The argument was that the people were close to death and would not survive many days or even hours without help,” Jeffrey said. “Even though the pacemaker was untested and had its problems, Greatbatch and Chardack said it was better than the alternative.”

The first patient, a 77-year-old man, lived 18 months with the pacemaker. Another patient was a young man who had collapsed at his job in a rubber factory. The pacemaker enabled him to live 30 more years and enjoy a new profession as a hairdresser.

Mr. Greatbatch licensed his device to Medtronic, which was co-founded by Bakken. Today, Medtronic is one of the world’s largest medical device companies and a leading manufacturer of pacemakers — all derived from Mr. Greatbatch’s first designs.

Wilson Greatbatch was born Sept. 6, 1919, in Buffalo. He became fascinated with electronics as a teenager and trained as an amateur radio operator. During World War II, he served as a Navy radio repairman and rear gunner on bomber sorties.

On the GI Bill, he graduated from Cornell University in 1950 with a bachelor’s degree in electrical engineering. He received a master’s degree in electrical engineering from the University of Buffalo in 1957.

Mr. Greatbatch was inspired to research new battery technology after observing that standard pacemaker batteries filled with zinc and mercury had to be replaced every two years.

In 1970, Mr. Greatbatch formed his own company to make lithium iodine batteries for pacemakers. His batteries often lasted more than 10 years.

For his contributions to science, Mr. Greatbatch received the National Technology Medal in 1990 from President George H.W. Bush. He was inducted into the National Inventors Hall of Fame in 1986.

Mr. Greatbatch’s wife of 66 years, the former Eleanor Wright, died in January. Their son Peter Greatbatch died in 1998.

Survivors include four children, Anne Maciariello of Sarasota, Fla., Warren Greatbatch of Buffalo, Kenneth Greatbatch of Swanzey, N.H., and John Greatbatch of Paris, Ky.; 12 grandchildren; and eight great-grandchildren.

In his later years, Mr. Greatbatch researched renewable energy. On his 72nd birthday, he sailed 150 miles in New York’s Finger Lakes in a solar-powered canoe he invented.