Our Story: Our First Pacemakers
In the mid-1950s, Earl Bakken became acquainted with Dr. C. Walton Lillehei, a pioneer in open heart surgery at the University of Minnesota Medical School. At that time, Dr. Lillehei and other surgeons discovered that heart block occurred after corrective heart surgery in about 10% of their patients. Silk sutures used in patching the defect interfered with the heart's electrical impulses, causing abnormally slow rates that were not sufficient to carry a patient through recovery.
Dr. C. Walton Lillehei with a child who received one of the early Medtronic external pacemakers.
While external pacemakers existed to help regulate heart rhythm, they were bulky, relied on external electrodes, and had to be plugged into a wall outlet. These AC-operated pacemakers could fail during a power blackout.
So Dr. Lillehei and his colleagues set out to develop a better system with the help of Medtronic engineers. Earl developed a new kind of pacemaker that was not much larger than a paperback book. He borrowed parts from other electrical devices he had in the shop. For the new device's circuitry, he relied on a design for a transistorised metronome he had seen in a trade publication. When finished, he produced a pacemaker that was powered by mercury batteries, provided a 9-volt DC pulse, and could easily and comfortably be worn by young patients.
The original Bakken pacemaker was tested in the University of Minnesota's laboratory. The following day, it was applied to a paediatric heart block patient. The effect was instantaneous. The pacemaker immediately restored the child's heartbeat to near normal. Within days, the child's heart resumed a normal rhythm on its own, and the pacemaker was removed.
The development of the wearable, external, battery-powered pacemaker amounted to a leap forward in the treatment of heart block and other cardiac problems. It also signaled the beginning of a new era in the therapeutic application of electrical stimulation for patients around the world.
Expanding Use of External Pacemakers
By 1960, Medtronic had established itself as a manufacturer of biomedical devices. External pacemakers were in use at the Mayo Clinic in Rochester, Minnesota; the University of Minnesota in Minneapolis; the National Institutes of Health in Bethesda, Maryland; Walter Reed Army Medical Center in Washington, DC; and Mount Zion Hospital in San Francisco. Medtronic pacemakers had also been sold in Australia, Africa, Canada, Cuba, Europe, and South America.
In most cases, the external pacemaker was used by patients recovering from open heart surgery. Several physicians, however, were beginning to recognise the value of the device in treating patients suffering from chronic heart block. Yet long-term application presented several problems: an external pacemaker worn 24 hours a day was inconvenient for the patient; the wires could become dislodged from the heart; and, most importantly, the passage of wires through the skin to the heart introduced the possibility of infection.
Success With Implantable Pacemakers
In the United States, the first successful attempts at designing a totally implantable pacemaker were reported by Drs. William Chardack and Andrew Gage at the Veterans Administration Hospital in Buffalo, New York, and Wilson Greatbatch, an electrical engineer. The three men carried out more than two years of experimental work and testing, then published a paper about their work in 1960.
Medtronic's founders read the article with interest and soon contacted the New York researchers. Palmer Hermundslie flew his own plane to Buffalo to meet Dr. Chardack and Greatbatch, and signed a contract giving Medtronic exclusive rights to produce and market the Chardack-Greatbatch implantable pulse generator. Within two months of beginning production in late 1960, Medtronic had received orders for 50 of the $375 implantable units.
Co-founder Palmer Hermundslie often piloted his own plane to make emergency deliveries of pacemakers.
At the same time, Medtronic appointed Picker International Corporation of White Plains, New York, as its sole distributor outside the United States, exclusive of Canada. Picker's 72 foreign sales offices greatly expanded the marketing efforts of Medtronic, which had 14 sales representatives covering the United States and Canada.
In addition to the implantable pacemaker, the representatives sold seven other Medtronic products, including the Telecor, which visibly and audibly monitored heart activity; the Cardiac Sentinel, an automatic alarm that summoned aid when the patient's heart activity became critical and stimulated the heart with an electronically regulated pulse; and a Coagulation Generator, used to control bleeding during surgery without damaging nearby tissue.
A Mission Is Born
The company reached another milestone in 1960. To bring clarity to the company's future, co-founder Earl Bakken wrote the Medtronic Mission statement. More than 40 years later, the Mission has been translated into many languages and continues to be the guiding force for our day-to-work.