Medtronic had a modest beginning. It was formed as a partnership in April, 1949, by Earl Bakken and Palmer Hermundslie. The two men thought of the idea while talking about Earl's part-time work at Northwestern Hospital in Minneapolis.

Earl had become familiar with the staff at Northwestern while waiting after work for his wife, a medical technologist. The staff soon learned Earl was a graduate student in electrical engineering at the University of Minnesota, and began asking him to repair electronic hospital equipment. Hospital engineers could service heavy machinery, but were not trained to repair more delicate laboratory equipment.

Earl and Palmer recognized their opportunity. Earl left his graduate studies, Palmer quit his job with a local lumber firm, and together they formed a medical equipment repair company they named Medtronic.

The two men set up shop in a 600-square-foot garage in northeast Minneapolis. The walls were built with lumber from refrigerator boxcars, and steel bars, salvaged from an old bank, protected the windows. Electric mats on the floor and a pot-bellied stove provided warmth in the winter, water sprayed on the roof in the summer became the air-conditioning system, and hand-built benches and desks served as the furniture.

Its first year as a service company was rough for Medtronic--in one month, it grossed exactly $8 for repair of a centrifuge. In the second year, Earl and Palmer began representing several medical equipment manufacturers in the Upper Midwest, and Medtronic started to grow.

From Service Company to Technological Innovator

As the servicing business grew and new employees were added, Medtronic expanded into a second garage and eventually occupied an apartment on Central Avenue. More than half of the company's revenues in the early 1950s was realized on sales of other manufacturer's products.

While selling and servicing this equipment, Earl and Palmer became well-acquainted with doctors and nurses throughout the Midwest--among them the staff members of medical research laboratories. Frequently, the research teams asked Medtronic engineers to modify equipment or design and produce new devices needed for special tests. The company responded by building single-use, custom-made products, and thereby entered the manufacturing business.

Although Medtronic built nearly 100 different custom devices during the 1950s, only 10 were actually part of the product line. These included two defibrillators, forceps, an animal respirator, a cardiac rate monitor, and a physiologic stimulator.

Early Pacemaker Research

In the mid-1950s, Medtronic 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 cases. 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.

For some time--in fact, since 1803--physicians knew that electricity was effective in stimulating heart activity. However, pacemakers of the late 1950s were bulky, relied on external electrodes, and had to be plugged into a wall outlet. External electric shocks were frequently too traumatic for young heart block patients, and the AC-operated pacemaker could fail during a power blackout.

Dr. Lillehei and his colleagues set out to develop a better system, and Medtronic engineers became closely involved in their work. By 1957, the research team discovered that by combining a pulse generator with a wire electrode attached directly to the hearts of dogs, heart rates could be controlled.

A pacemaker system was then applied successfully to heart block patients, but physicians still needed to tackle the problems of size and the inconvenient and unreliable power source. When a power failure knocked out power in the Twin Cities and resulted in the death of one of Dr. Lillehei's young patients, the surgeon turned to Earl and Medtronic for a battery back-up for the AC pacemakers. Over the next few weeks, Earl developed a new kind of pacemaker that was not much larger than a paperback book. He borrowed parts from other electrical devices that he had in the shop. For the new device's circuitry, he relied on a design for a transistorized metronome he had seen in a trade publication. When finished, he had 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.

That original Bakken pacemaker was tested in the University's laboratory; the following day, it was applied to a pediatric 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 technology for patients around the world.

The Hunter-Roth Electrode

The next step in the development of pacing was to improve the electrode system. Surgeons found that the single wire electrode occasionally dislodged from the heart or broke; also, the heart's demand for current increased over time.

The first major improvement in pacing electrodes was developed by Dr. Samuel Hunter of St. Joseph's Hospital research laboratory in St. Paul, and Norman Roth, an electrical engineer at Medtronic. They designed a plastic patch with two imbedded needle-like electrodes. This patch was sutured to the heart, concentrating the electrical field where it was needed instead of allowing the current to pass through the body between the internal and external electrodes. The system required about 70% less current than the previous pacemaker system. The Hunter-Roth electrode was first implanted in 1958 in a patient who recovered and lived an additional and active 7 1/2 years.

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, the University of Minnesota in Minneapolis, the National Institutes of Health in Bethesda, Maryland, Walter Reed Army Medical Center in Washington, D.C., and Mount Zion Hospital in San Francisco. Medtronic pacemakers had also been sold in Africa, Australia, 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 recognize 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 important, the passage of wires through the skin to the heart introduced the possibility of infection.

The First Implantable Pacemaker

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 from upstate New York. Together, they carried out more than two years of experimental work and testing on dogs before they published a paper in 1960 entitled: A transistorized, self-contained, implantable pacemaker for the long-term correction of complete heart block.

A simple addendum to that paper recorded a milestone in the history of biomedical electronics: the world's first successful long-term implant in a human patient of a self-contained, internally powered pacemaker. The pacemaker, potted in epoxy resin, was coated with silicone rubber to protect it from body fluids, sterilized in a bag of ethylene oxide gas, and slipped through a skin incision in the left side of the abdomen. It included 10 battery cells and measured 65 mm in diameter and 15 mm thick.

The paper did not go unnoticed by Medtronic, whose founders soon contacted the New York researchers. On a rainy October evening in 1960, Palmer Hermundslie flew a private plane to Buffalo, met Dr. Chardack and Greatbatch in the airport, and signed a contract giving Medtronic exclusive rights to produce and market the Chardack-Greatbatch implantable pulse generator. Production of the implantables began in November, and by the end of December, 1960, Medtronic had received orders for 50 of the $375 units.

Rapid Technological Growth

After development of the implantable pacemaker in 1960, significant advancements in all areas of pacing occurred rapidly. Highlights of these are described below.

Transvenous leads. In the mid-1960s, Medtronic introduced its first transvenous pacing system, which used pacing leads that could be maneuvered through a vein to the heart without opening the chest or using general anesthesia. It was believed to be the only such unit manufactured in the United States at that time.

Tined leads. To overcome dislodgment problems with transvenous leads, Medtronic developed the first tined leads in the early 1970s. Tines (soft, pliant projections) at the lead tip allowed the lead to be more securely entrapped in the supporting structures of the heart, resulting in a more stable placement. The tined lead (including both ventricular and atrial J-shaped models) set a new industry standard.

Screw-in myocardial leads. For procedures that required open heart implants, Medtronic introduced the sutureless, screw-in lead in the early 1970s. Unlike other myocardial leads that required a stab wound and sutures for insertion, the sutureless lead had a unique screw-in electrode that simply rotated into the myocardium (the outside of the heart).

Other advancements in leads. Other important Medtronic developments in leads included screw-in transvenous leads; smaller lead diameters; smaller, thinner tines; improved insulation materials and conductor coils; and lead electrodes designed to reduce the energy needed to pace the heart.

Demand pacing. Another important step in pacing was the development of a system that avoided competition between the pacemaker's artificial beats and the patient's own heartbeats. These demand pacemakers were able to sense when the patient's heart was beating on its own and then provided pacing only when necessary. Medtronic introduced two demand pacemaker models--an external and an implantable unit--in 1967. Virtually all pacemakers manufactured today are demand models.

Power sources. Early pacemakers used mercury-zinc power sources that yielded expected longevities of 18-24 months. Lithium battery technology produced a more reliable and durable power source. Medtronic introduced its lithium-powered Xyrel pacemaker models in 1977. Now, advances in power sources and energy-efficient pacemakers and leads have extended pacemaker battery life to more than 10 years in some products.

Circuitry. In the early 1970s, hybrid circuitry contributed to a significant reduction in the size and weight of pacemakers. In the ensuing years, research into integrated circuits and microprocessors further reduced the size of pacemakers while expanding their capabilities. The Thera SR single chamber, rate responsive pacemaker, for example, is 28.9 mm high and 7 mm thick (compared to 65 mm high and 15 mm thick for the first implantable pacemaker developed in 1960).

Dual chamber pacing. Dual chamber pacing is designed to pace and synchronize both the upper and lower heart chambers. In 1979, Medtronic introduced its first dual chamber pacemaker, the Byrel. Since then, dual chamber pacemakers have gained wide acceptance in the medical community, particularly in the United States where they comprised 59% of all pacemakers implanted in 1994.

Succeeding generations of dual chamber devices have become significantly smaller yet have included a greater array of programmable parameters and other sophisticated features. While the Byrel was 70.5 mm high, 18.2 mm thick, and weighed 135 grams, the Thera DR dual chamber, rate responsive pacemaker is 51.3 mm high, 7 mm thick, and weighs 25.5 grams.

Multiprogrammable pacing. Developed in the late 1970s, noninvasive programmability allowed adjustment of pacemaker parameters to meet a patient's needs without performing another operation. In 1980, Medtronic introduced its first multiprogrammable pacemaker--the Spectrax SX device--with nine adjustable parameters. All modern pacemakers now have noninvasive multiprogrammability.

Rate responsive pacing. In the mid-1980s, Medtronic introduced its revolutionary rate responsive, activity sensing Activitrax pacing system. Until rate responsive pacing, single chamber pacemakers functioned at a fixed rate--generally about 70 beats per minute--regardless of the wearer's activity and blood-pumping requirements. In the Activitrax pacemaker, a tiny sensor detected pressure waves caused by a patient's muscle movement or body motion. The pacemaker's circuitry then translated the pressure waves into electrical signals that triggered the appropriate rate response from the pacemaker. Rate responsive pacemakers provided patients with a level of stamina and endurance not usually possible with fixed-rate pacing therapy.

Subsequent generations of Medtronic rate responsive, activity sensing pacemakers have incorporated dual chamber pacing. Others have used different sensors, including one that detects changes in the frequency and depth of a patient's breathing.

Serving the Customer

From the early days, customer service was an essential component of Medtronic's operations. At one time, Earl Bakken, screwdriver in hand, tended to electrical problems in local operating rooms, and Palmer Hermundslie piloted his own airplane for emergency deliveries of the company's pacemakers. This hands-on, person-to-person customer service tradition continues today with a United States sales team that has doubled in size during the past 10 years and with hundreds of technical support staff members. Supplementing the face-to-face service are professionals who provide technical assistance 24 hours a day via toll-free telephones.

In international markets, Medtronic sales and technical support teams serve customers in more than 80 countries. Worldwide operations are grouped in three organizations: the Americas, Asia/Pacific, and Europe.

Customer Education

An essential element of service at Medtronic is customer education, which includes product training sessions, the sponsorship of major medical and scientific seminars and symposia throughout the world, and professionally accredited workshops.

The first Bakken Education Center, located at Medtronic's Fridley, Minnesota, headquarters, symbolizes the company's commitment to education. Dedicated in 1990, the center offers state-of-the-art classrooms, hands-on training areas, sophisticated audiovisual equipment, and other facilities to serve physicians, other health care professionals, and Medtronic's sales and technical support organization.

Additional Bakken Education Centers are located in various cities throughout the United States and in England, Germany, India, Japan, and The Netherlands. Thousands of physicians and associated medical professionals take part in learning sessions at the centers every year, and many others attend company-sponsored symposia at other locations.

Customer-Focused Quality Programs

Medtronic's emphasis on product quality began in the early days when a few employees hand-assembled products in a garage. Quality assurance in those days often meant a close, eyeball inspection by the entire technical staff. Though the means have changed over the years, the company's insistence on quality has continued with ongoing efforts in world-class manufacturing processes, meticulous product testing, and statistical quality controls.

In 1990, Medtronic began its Customer-Focused Quality (CFQ) process, which incorporated all Medtronic quality strategies, programs, and procedures, and expanded them throughout all levels of the organization worldwide. CFQ underscores a total commitment on the part of all Medtronic employees to focus on customers needs and wants by providing them with unsurpassed quality in Medtronics products, services, and relationships. Examples of Medtronic's ongoing quality efforts include:

• having sales representatives available 24 hours a day to ensure that customers have the appropriate products and support when needed,
• testing Medtronic mechanical heart valves over a span of more than one billion cycles--67% more than required by the United States Food and Drug Administrations guidelines,
• publishing a detailed product performance report--unique in the medical industry--that provides performance data on Medtronic's pacemakers and leads, and
• conducting customer satisfaction surveys for the collection and assessment of perceptions and imperatives.