Telectronics
Encyclopedia
Telectronics Pty Ltd was an Australian company best known for its role in developing the pacemaker
. In 1988 the business was acquired by Pacific Dunlop
. However, legal claims resulting from the sale of faulty pacemaker electrode leads inherited by the company in acquisition of Cordis
Corporation of Miami led to eventual sale of the assets of the company and Pacific Dunlop restructuring itself into Ansell.
and Geoffrey Wickham
initially designing and manufacturing industrial and scientific instruments but diversifying into medical electronics and commencing cardiac pacemaker research in 1964.. The corporate name was derived from "Television and Electronic Services", operated by Noel Gray as a sole trader from 1959-1964.
The company made significant contributions to pacemaker technology including the first definition of the relationship between surface area of the heart electrodes & pacing pulse characteristics, the first use of integrated circuits and the first hermetic
titanium
encapsulation.
The company's first model, designated P1, was implanted in three volunteer terminally ill patients in December '64 - January'65, while 2 control samples were retained in a 37 °C. saline bath. This initial design used PNP - NPN electronics to deliver a 2.0 millisecond
pulse to the Jeffcoat epicardial
electrodes, and was powered by 4 Mallory mercuric oxide-zinc cells (mercury battery
), all encapsulated in epoxy
resin with a final dip coat of a mix of epoxy and titanium dioxide
. All 3 implants failed in ability to maintain capture of the heart after periods of up to 35 weeks. These failures were later proven to be due to the excessively large surface area of the electrodes.
The initial clinical experience led to further animal research using mongrel
dogs at the laboratories of the University of Sydney
medical school and at the Royal North Shore Hospital
's Wellcome laboratory. In this research measurements were made of electrode impedance
and pacing threshold energy over a range of pulse voltages and pulse widths, using intramyocardial electrodes of 10, 20 & 50 square millimeters surface area. The chronic measurements allowed plotting of the relationship between electrode surface area and pulse voltage/width, leading to a conclusion that an electrode area between 10 & 30 mm2 was optimum in terms of energy needed when combined with a pulse width of only 0.5 milliseconds.
These characteristics were incorporated in the next design to be implanted in humans, the model P4, which employed 30 mm2 area intramyocardial electrodes (and later transvenous pacing
electrodes), a very conservative 7.5 volt pulse and for further conservatism a magnetically operated switch which could be actuated from outside the body to change the pulse width from 0.5 to 1.0 millisecond.
The 0.5 millisecond pulse width became the standard for later Telectronics models and became the approximate standard for all pacemaker manufacturers by the late 70's, until the evolution of externally programmable/monitorable pacemakers using digital electronics in the late 1980s.
Research also included dissection
and analysis of the failure modes of explanted pacemakers of any manufacturer. Most failures were due to an internal short circuit of one of the cells of the multicell battery due to the growth of metallic dendrites; or the result of water vapour diffusing though the epoxy resin encapsulation. The only suitable cell available at the time was the mercuric oxide-zinc cell, so the battery problems remained. In 1967 Telectronics commenced research into the technologies which could allow hermetic seal
ing of the pacemaker to preclude water vapour penetration and, as an interim measure contracted AWM a subsidiary of Amalgamated Wireless Australia Limited (AWA
) to develop integrated circuits for the electronics. These early integrated circuits were developed by David R Money who later joined Telectronics and later still led development of the cochlear implant
for the profoundly deaf. The circuits were analogue type, housed in hermetically sealed ceramic military 'flat packs' with redundant double gold bonding of the terminations. The IC's were first used in the model P7 of 1969.
The first hermetically sealed models were the P8-9-10 of 1971 using titanium
encapsulation with ceramic
terminal insulation, developed by David J Cowdery. Bonding of the ceramic was performed using vacuum
brazing
and an alloy of titanium/nickel with a small % of copper. The final hermetic sealing of the titanium capsule was performed by a TIG
tungsten-inert gas argon
welding
process within a large bell jar
on an automated analogue controlled machine designed and built by Cowdery. These were the first pacemakers using the conventional battery to be hermetically sealed. Gas products of the battery were absorbed by a chemical 'getter'. Some examples of these models survived to beyond 5 years. By the late 80's TIG welding was replaced by laser welding.
In 1971 Telectronics commenced testing samples of a new type of energy source for pacemakers, the lithium cell (lithium battery
) being developed by Wilson Greatbatch
and in 1972 commenced development of a range of integrated circuits capable of operation from the 2.8 volts of the cell while providing a stimulating pulse of 4.5 volts. The combined technologies of a lithium cell, integrated circuits, hermetic titanium casing and an 0.5 millisecond pulse was first used clinically in 1974 in the model 120 pacemaker which was state of the art
for that time. In 1981 a study of 28'669 Telectronics lithium powered implants showed a cumulative survival of 99.88% and a MTTF of 12'260 months. The longest surviving model 120 was electively explanted in 1993 after 17 years of operation.
Control of Telectronics was gained in 1967 by Nucleus Holdings. Telectronics Inc. was incorporated in the USA in 1974, and in 1977 commenced US manufacture from the former General Electric
facility in Milwaukee, later relocating to Denver. A manufacturing plant was also established at Châtellerault
France, in 1978.
was acquired by Pacific Dunlop. At that time Nucleus Limited contained offshoots such as Telectronics, Medtel, Ausonics, Domedica and Cochlear Pty Ltd
. Cochlear Limited which developed the cochlear implant
was floated on the Australian stock market. Pacific Dunlop was hoping to diversify away from so-called rustbelt companies. At the time of acquisition, Telectronics was number 2 in the worldwide pacemaker market.
In January 1995, Telectronics was forced to recall thousands of pacemakers by the Food and Drug Administration
leading to the company having to eventually settle legal claims at a cost of hundreds of millions of dollars. The cause of the recall was a "J lead" electrode, utilizing a rigid stylet within the helix of the electrode lead, inherited by the company in acquisition of pacemaker manufacturer Cordis
Corporation of Miami. The inherent dangers arising from incorporation of a rigid stylet had been demonstrated by Telectronics, Sydney, in 1967.
In 1996 Pacific Dunlop sold most of the assets of Telectronics Limited to St Jude Medical of Minnesota
and Telectronics Pty Limited is now a shelf company TPLC Pty. Ltd. Pacific Dunlop restructured in 2001 becoming Ansell
with the high cost of the Telectronics settlement being a contributing factor in the decision.
Artificial pacemaker
A pacemaker is a medical device that uses electrical impulses, delivered by electrodes contacting the heart muscles, to regulate the beating of the heart...
. In 1988 the business was acquired by Pacific Dunlop
Ansell
-Other:*Ansell's Shrew*Ansell's Mole Rat - rodent*Ansell's Epauletted Fruit Bat - megabat*Ansell Limited - medical gloves and condom manufacturer...
. However, legal claims resulting from the sale of faulty pacemaker electrode leads inherited by the company in acquisition of Cordis
Cordis
Cordis may refer to:* Cordis , a medical device company owned by Johnson & Johnson* Community Research & Development Information Service...
Corporation of Miami led to eventual sale of the assets of the company and Pacific Dunlop restructuring itself into Ansell.
Development of the pacemaker
Telectronics Pty Limited was incorporated in Sydney, Australia, in 1963 by engineers Noel GrayNoel Gray
Noel Desmond Gray was an Australian technician, co-founder and initial financier of the medical electronics company Telectronics Pty Ltd.-Early life:...
and Geoffrey Wickham
Geoffrey Wickham
Geoffrey Gordon Wickham AO MIIE was one of the pioneers of cardiac pacemaking, born at Camperdown, Victoria, Australia to dairy farmer parents on 28 October 1933.In 1963 he co-founded the medical instruments company Telectronics Pty Ltd in Sydney, and served as the company's Technical Director from...
initially designing and manufacturing industrial and scientific instruments but diversifying into medical electronics and commencing cardiac pacemaker research in 1964.. The corporate name was derived from "Television and Electronic Services", operated by Noel Gray as a sole trader from 1959-1964.
The company made significant contributions to pacemaker technology including the first definition of the relationship between surface area of the heart electrodes & pacing pulse characteristics, the first use of integrated circuits and the first hermetic
Hermetic seal
A hermetic seal is the quality of being airtight. In common usage, the term often implies being impervious to air or gas. When used technically, it is stated in conjunction with a specific test method and conditions of usage.-Etymology :...
titanium
Titanium
Titanium is a chemical element with the symbol Ti and atomic number 22. It has a low density and is a strong, lustrous, corrosion-resistant transition metal with a silver color....
encapsulation.
Millisecond
A millisecond is a thousandth of a second.10 milliseconds are called a centisecond....
pulse to the Jeffcoat epicardial
Epicardial
Epicardial is a term used by some cardiac surgeons meaning "on the outside of the cardiac muscle". Epicardial fat or Epicardial adipose tissue is one of the most important parts of pericardium.See also epicardium....
electrodes, and was powered by 4 Mallory mercuric oxide-zinc cells (mercury battery
Mercury battery
A mercury battery is a non-rechargeable electrochemical battery, a primary cell. Due to the content of mercury, and the resulting environmental concerns, the sale of mercury batteries is banned in many countries. Both ANSI and IEC have withdrawn standards for mercury batteries...
), all encapsulated in epoxy
Epoxy
Epoxy, also known as polyepoxide, is a thermosetting polymer formed from reaction of an epoxide "resin" with polyamine "hardener". Epoxy has a wide range of applications, including fiber-reinforced plastic materials and general purpose adhesives....
resin with a final dip coat of a mix of epoxy and titanium dioxide
Titanium dioxide
Titanium dioxide, also known as titanium oxide or titania, is the naturally occurring oxide of titanium, chemical formula . When used as a pigment, it is called titanium white, Pigment White 6, or CI 77891. Generally it comes in two different forms, rutile and anatase. It has a wide range of...
. All 3 implants failed in ability to maintain capture of the heart after periods of up to 35 weeks. These failures were later proven to be due to the excessively large surface area of the electrodes.
The initial clinical experience led to further animal research using mongrel
Mixed-breed dog
A mixed-breed dog, also known as a mutt or mongrel, is a dog whose ancestry is generally unknown and that has characteristics of two or more types of breeds. A mixed-breed may be a cross-breed dog, a random-bred dog, or a descendant of feral or pariah dog populations...
dogs at the laboratories of the University of Sydney
University of Sydney
The University of Sydney is a public university located in Sydney, New South Wales. The main campus spreads across the suburbs of Camperdown and Darlington on the southwestern outskirts of the Sydney CBD. Founded in 1850, it is the oldest university in Australia and Oceania...
medical school and at the Royal North Shore Hospital
Royal North Shore Hospital
The Royal North Shore Hospital is a major public teaching hospital in Sydney, Australia, located in St Leonards. It serves as a teaching hospital for Sydney Medical School at the University of Sydney and has approximately 740 beds. It is the referral hospital for Northern Sydney and the Central...
's Wellcome laboratory. In this research measurements were made of electrode impedance
Electrical impedance
Electrical impedance, or simply impedance, is the measure of the opposition that an electrical circuit presents to the passage of a current when a voltage is applied. In quantitative terms, it is the complex ratio of the voltage to the current in an alternating current circuit...
and pacing threshold energy over a range of pulse voltages and pulse widths, using intramyocardial electrodes of 10, 20 & 50 square millimeters surface area. The chronic measurements allowed plotting of the relationship between electrode surface area and pulse voltage/width, leading to a conclusion that an electrode area between 10 & 30 mm2 was optimum in terms of energy needed when combined with a pulse width of only 0.5 milliseconds.
These characteristics were incorporated in the next design to be implanted in humans, the model P4, which employed 30 mm2 area intramyocardial electrodes (and later transvenous pacing
Transvenous pacing
Transvenous cardiac pacing, also called endocardial pacing, is a potentially life saving intervention used primarily to correct profound bradycardia. It can be used to treat symptomatic bradycardias that do not respond to transcutaneous pacing or to drug therapy...
electrodes), a very conservative 7.5 volt pulse and for further conservatism a magnetically operated switch which could be actuated from outside the body to change the pulse width from 0.5 to 1.0 millisecond.
The 0.5 millisecond pulse width became the standard for later Telectronics models and became the approximate standard for all pacemaker manufacturers by the late 70's, until the evolution of externally programmable/monitorable pacemakers using digital electronics in the late 1980s.
Research also included dissection
Dissection
Dissection is usually the process of disassembling and observing something to determine its internal structure and as an aid to discerning the functions and relationships of its components....
and analysis of the failure modes of explanted pacemakers of any manufacturer. Most failures were due to an internal short circuit of one of the cells of the multicell battery due to the growth of metallic dendrites; or the result of water vapour diffusing though the epoxy resin encapsulation. The only suitable cell available at the time was the mercuric oxide-zinc cell, so the battery problems remained. In 1967 Telectronics commenced research into the technologies which could allow hermetic seal
Hermetic seal
A hermetic seal is the quality of being airtight. In common usage, the term often implies being impervious to air or gas. When used technically, it is stated in conjunction with a specific test method and conditions of usage.-Etymology :...
ing of the pacemaker to preclude water vapour penetration and, as an interim measure contracted AWM a subsidiary of Amalgamated Wireless Australia Limited (AWA
Amalgamated Wireless Australasia Limited
Amalgamated Wireless Ltd . Throughout most of the 20th century AWA was Australia's largest and most prominent electronics organisation, undertaking development, manufacture and distribution of radio, telecommunications, television and audio equipment as well as broadcasting services.After the...
) to develop integrated circuits for the electronics. These early integrated circuits were developed by David R Money who later joined Telectronics and later still led development of the cochlear implant
Cochlear implant
A cochlear implant is a surgically implanted electronic device that provides a sense of sound to a person who is profoundly deaf or severely hard of hearing...
for the profoundly deaf. The circuits were analogue type, housed in hermetically sealed ceramic military 'flat packs' with redundant double gold bonding of the terminations. The IC's were first used in the model P7 of 1969.
The first hermetically sealed models were the P8-9-10 of 1971 using titanium
Titanium
Titanium is a chemical element with the symbol Ti and atomic number 22. It has a low density and is a strong, lustrous, corrosion-resistant transition metal with a silver color....
encapsulation with ceramic
Ceramic
A ceramic is an inorganic, nonmetallic solid prepared by the action of heat and subsequent cooling. Ceramic materials may have a crystalline or partly crystalline structure, or may be amorphous...
terminal insulation, developed by David J Cowdery. Bonding of the ceramic was performed using vacuum
Vacuum
In everyday usage, vacuum is a volume of space that is essentially empty of matter, such that its gaseous pressure is much less than atmospheric pressure. The word comes from the Latin term for "empty". A perfect vacuum would be one with no particles in it at all, which is impossible to achieve in...
brazing
Brazing
Brazing is a metal-joining process whereby a filler metal is heated above and distributed between two or more close-fitting parts by capillary action. The filler metal is brought slightly above its melting temperature while protected by a suitable atmosphere, usually a flux...
and an alloy of titanium/nickel with a small % of copper. The final hermetic sealing of the titanium capsule was performed by a TIG
Tig
Tig may refer to:*Tig Notaro, an American stand-up comic*Tig, another name for tag *Alex "Tig" Trager, a character in Sons of AnarchyTIG may refer to:*Tungsten inert gas welding, aka gas tungsten arc welding...
tungsten-inert gas argon
Argon
Argon is a chemical element represented by the symbol Ar. Argon has atomic number 18 and is the third element in group 18 of the periodic table . Argon is the third most common gas in the Earth's atmosphere, at 0.93%, making it more common than carbon dioxide...
welding
Welding
Welding is a fabrication or sculptural process that joins materials, usually metals or thermoplastics, by causing coalescence. This is often done by melting the workpieces and adding a filler material to form a pool of molten material that cools to become a strong joint, with pressure sometimes...
process within a large bell jar
Bell jar
A bell jar is a piece of laboratory equipment used for creating vacuums.http://www.belljar.net/about.htm It can be similar in shape to a bell, and can be manufactured out of a variety of materials . A bell jar is placed on a base which is vented to a hose fitting, which can be connected via a hose...
on an automated analogue controlled machine designed and built by Cowdery. These were the first pacemakers using the conventional battery to be hermetically sealed. Gas products of the battery were absorbed by a chemical 'getter'. Some examples of these models survived to beyond 5 years. By the late 80's TIG welding was replaced by laser welding.
In 1971 Telectronics commenced testing samples of a new type of energy source for pacemakers, the lithium cell (lithium battery
Lithium battery
Lithium batteries are disposable batteries that have lithium metal or lithium compounds as an anode. Depending on the design and chemical compounds used, lithium cells can produce voltages from 1.5 V to about 3.7 V, over twice the voltage of an ordinary zinc–carbon battery or alkaline battery...
) being developed by Wilson Greatbatch
Wilson Greatbatch
Wilson Greatbatch was an American engineer and inventor whois most widely known as the inventor of the implantable cardiac pacemaker...
and in 1972 commenced development of a range of integrated circuits capable of operation from the 2.8 volts of the cell while providing a stimulating pulse of 4.5 volts. The combined technologies of a lithium cell, integrated circuits, hermetic titanium casing and an 0.5 millisecond pulse was first used clinically in 1974 in the model 120 pacemaker which was state of the art
State of the art
The state of the art is the highest level of development, as of a device, technique, or scientific field, achieved at a particular time. It also refers to the level of development reached at any particular time as a result of the latest methodologies employed.- Origin :The earliest use of the term...
for that time. In 1981 a study of 28'669 Telectronics lithium powered implants showed a cumulative survival of 99.88% and a MTTF of 12'260 months. The longest surviving model 120 was electively explanted in 1993 after 17 years of operation.
Control of Telectronics was gained in 1967 by Nucleus Holdings. Telectronics Inc. was incorporated in the USA in 1974, and in 1977 commenced US manufacture from the former General Electric
General Electric
General Electric Company , or GE, is an American multinational conglomerate corporation incorporated in Schenectady, New York and headquartered in Fairfield, Connecticut, United States...
facility in Milwaukee, later relocating to Denver. A manufacturing plant was also established at Châtellerault
Châtellerault
Châtellerault is a commune in the Vienne department in the Poitou-Charentes region in France.It is located to the north of Poitou, and the residents are called Châtelleraudais.-Geography:...
France, in 1978.
Pacific Dunlop
In 1988 Nucleus LimitedNucleus Limited
Nucleus Limited began as a private company in Sydney, Australia, in 1965. It was founded by former Watson-Victor executive Paul Murray Trainor, after acquisition of X-ray sales & service company Scientific & General....
was acquired by Pacific Dunlop. At that time Nucleus Limited contained offshoots such as Telectronics, Medtel, Ausonics, Domedica and Cochlear Pty Ltd
Cochlear Limited
Cochlear Limited is an Australian company that designs, manufactures and sells the Nucleus Cochlear implant along with the Bone Conduction Hearing Solution Baha osseointegrated bone conduction implant, with an estimated 250 000 cochlear implant/Baha recipients receiving a Cochlear Limited product...
. Cochlear Limited which developed the cochlear implant
Cochlear implant
A cochlear implant is a surgically implanted electronic device that provides a sense of sound to a person who is profoundly deaf or severely hard of hearing...
was floated on the Australian stock market. Pacific Dunlop was hoping to diversify away from so-called rustbelt companies. At the time of acquisition, Telectronics was number 2 in the worldwide pacemaker market.
In January 1995, Telectronics was forced to recall thousands of pacemakers by the Food and Drug Administration
Food and Drug Administration
The Food and Drug Administration is an agency of the United States Department of Health and Human Services, one of the United States federal executive departments...
leading to the company having to eventually settle legal claims at a cost of hundreds of millions of dollars. The cause of the recall was a "J lead" electrode, utilizing a rigid stylet within the helix of the electrode lead, inherited by the company in acquisition of pacemaker manufacturer Cordis
Cordis
Cordis may refer to:* Cordis , a medical device company owned by Johnson & Johnson* Community Research & Development Information Service...
Corporation of Miami. The inherent dangers arising from incorporation of a rigid stylet had been demonstrated by Telectronics, Sydney, in 1967.
In 1996 Pacific Dunlop sold most of the assets of Telectronics Limited to St Jude Medical of Minnesota
Minnesota
Minnesota is a U.S. state located in the Midwestern United States. The twelfth largest state of the U.S., it is the twenty-first most populous, with 5.3 million residents. Minnesota was carved out of the eastern half of the Minnesota Territory and admitted to the Union as the thirty-second state...
and Telectronics Pty Limited is now a shelf company TPLC Pty. Ltd. Pacific Dunlop restructured in 2001 becoming Ansell
Ansell
-Other:*Ansell's Shrew*Ansell's Mole Rat - rodent*Ansell's Epauletted Fruit Bat - megabat*Ansell Limited - medical gloves and condom manufacturer...
with the high cost of the Telectronics settlement being a contributing factor in the decision.