Cardiac pacemakers
Some time ago, my friend and colleague Paul Spehr gave me a copy of Arco Medical’s product catalog. I scanned the original datasheets for Arco Medical’s nuclear fixed-rate and demand pacemakers models NU-5 and NU-6 and posted them here in pdf format: Arco_Nuclear_Datasheets
Click here for a color picture and more information on Arco Medical’s nuclear pacemakers.
The Cardio Care II Pacemaker was American Optical’s second implantable device. It was an improved version of the Cardio Care pacemaker. Besides improvements to the circuitry, the circuit board was enclosed separately inside a hermetic can within the epoxy encapsulation. Continue reading
Barouh Berkovits at American Optical Co of Boston, MA designed the first “Demand Pacemaker” – what we now know as a VVI pacemaker. The Cardio-Care Demand Pacemaker, introduced in 1968, was American Optical’s first implantable device.
From Kirk Jeffrey’s Machines in our Hearts(2001):
“Berkovits in 1963 designed a sensing capability into the pacemaker. His invention behaved exactly like an asynchronous pacer until it detected a naturally occurring R wave, the indication of a ventricular contraction. This event would reset the timing circuit of the pacemaker, and the countdown to the next stimulus would begin anew. Thus the pacer stimulated the heart only when the ventricles failed to contract. It worked only ‘‘on demand.’’ As an added benefit, noncompetitive pacing extended the life of the battery. Continue reading
Biotectix of Ann Arbor, MI recently contacted me to let me know of new conductive polymer materials that they are developing to enhance the performance of next-gen implantable stimulation and sensing devices.
Indeed, their materials sound very promising. According to Biotectix, their electrode coatings and device components are made from proprietary conducting polymers that provide intimate, long-term electrical and biological connections between implantable electrodes and the target tissue. They offer the conductivity and stability of metals at a low-cost with the ease of processing and biological functionality of polymers. Continue reading
I took this picture a very long time ago at the office of one of my implanter friends in Europe. Ever since then, I’ve tried to find out about “Digikon,” but have had no luck so far. All that I have been able to find from the St. Jude legacy device database is that Digikon had produced a number of pacemaker models, including the one shown in this picture.
In 1983, Bill Cook and Dr. Neal Fearnot began to work under the Cook Pacemaker Company in Leechburg, PA on developing the technology developed by Dr. Fearnot at Purdue University into an improved prototype for a temperature-based exercise responsive pacemaker that was released in 1988 as the Kelvin Sensor rate-responsive pacemaker. One of the first CVT rate-adaptive pacemakers was the Cook Model Kelvin 500 series. Continue reading
The Circadia pacemaker was one of the very few devices that had a lead-borne thermistor to measure cental venous temperature (CVT) as a sensor for rate-response.
A unique feature of this pacemaker was an iridium-oxide (IrOx)-coated button welded to the can. It was believed that this button would improve unipolar IEGM sensing and reduce unipolar pacing thresholds (it didn’t). Continue reading
One of the indicators of metabolic demand that has been used for controlling the rate of pacemakers is central venous blood temperature (CVT).
In 1983, Bill Cook and Dr. Neal Fearnot began to work under the Cook Pacemaker Company on developing the technology developed by Dr. Fearnot at Purdue University into an improved prototype for a temperature-based exercise responsive pacemaker that was released in 1988 as the Kelvin Sensor rate-responsive pacemaker. One of the first CVT rate-adaptive pacemakers was the Cook Model Kelvin 500 series.
Another one of the first CVT rate-adaptive pacemakers was the Intermedics Nova MR, which differs from the Kelvin 500 series in that its pacing algorithm had a more dynamic HR response. Continue reading
Medcor was established in Hollywood, FL in 1969, and began developing pacemakers, lead and accessories in 1971. By 1975 it had a series of lithium-powered pacemaker in the market, but they never became popular with physicians.
On July 1980, Daig Corporation of Minnetonka, MN acquired Medcor with the expectation that Medcor pacemaker technology could be profitably marketed.
Daig had hoped to market a new line of Medcor pacemakers, but significant electronic malfunctions were encountered which foreclosed further development Medcor’s pacemaker product line. As a result of malfunctions in the first pacemaker line, FDA approval was withheld on a second Medcor line of pacemakers due to similarities in product design.
In 1981, amidst a very serious financial condition, Daig closed its doors. The remaining assets were acquired by Daig’s largest customer – Pacesetter (now part of St. Jude Medical).
UPDATE, May 20, 2013:
Mark Christensen – who worked at Daig Corporation from 1980 to 1986 – sent me a kind note with some additional information: “As you note in your comments on Medcor, it was purchased by Daig in 1980 but remained as a separate business. Daig’s financial crisis in 1981 caused Daig to go into Chapter 11 Bankruptcy and Medcor went to Chapter 7 – liquidation and was sold at auction in late 1981. No pacemaker company bought any of the assets. Daig reorganized, diversified into EP catheters and was bought by St Jude Medical in 1996 (15 years later).” Thanks Mark!
Medtronic announced at TEDMED 2010 that it is working on leadless pacemakers. Dr. Stephen Osterle, senior vice president of medicine and technology and member of Medtronic’s Executive Management Team, unveiled the device. Osterle said that physicians will be able to control the device with a smart phone.
EBR Systems, Inc., founded in 2003 and headquartered in Sunnyvale, CA, is developing the WiCS® Wireless Cardiac Stimulation technology to eliminate cardiac pacing leads, historically a major source of complications and reliability issues. The startup was spun out of research by founder Debra Echt, a former professor of medicine and a cardiologist at Vanderbilt University. Continue reading
Nanostim is an early-stage AIMD company in Milpitas, CA that is developing a pacemaker that can be implanted inside the heart through a catheter. The tiny device is attached directly to the heart, eliminating the need for leads.
In May 2011 Nanostim announced that St. Jude Medical had made a substantial investment in the company.
The company is operating in stealth mode, but some details about the leadless pacemaker have emerged from Nanostim’s patents and patent applications. An interesting detail is about the possible use of a betavoltaic power source: Continue reading
Barouh Berkovits at American Optical Co of Boston, MA designed the first “Demand Pacemaker” – what we now know as a VVI pacemaker. As other companies in the 1970s, American Optical developed a nuclear-battery-powered version of their pacemaker.
American Optical used a 3Ci Pu-238 Radioisotope Thermal Generator (RTG) produced by Fred Hittman’s Hittman Nuclear Development Corp. (Model NB-200). It consisted of a tiny 8 Ci slug of metallic Plutonium 238 (Pu-238). The radiation produced by the Pu-238 bombarded the walls of its container, producing heat that a thermopile then converted to an electrical current. A thermopile is a stack of thermocouples, which are devices that convert thermal energy directly into electrical energy using Seebeck effect. The thermocouple was made of two kinds of metal (or semiconductors) connected to each other in a closed loop. If the two junctions are at different temperatures, an electric current will flow in the loop. Continue reading
Image Credit: Arco Medical Products Co. (1974)
An isotopic thermoelectric generator was developed in the US by Numec Corporation under a contract from the US Atomic Energy Commission and sold for $3,200 (back in 1974). The thermopile consisted of doped bismuth telluride pairs that were placed in a parallel/series arrangement to generate some 300 μW of power to run this Arco Medical model NU-5F pacemaker. Continue reading
In the late 1960s Medtronic – today the largest manufacturer of implantable medical devices in the world – teamed up with Alcatel, a French company, to design a nuclear-powered pacemaker. The first human implant of the device took place in Paris in 1970.
The nuclear battery in the Medtronic device used a tiny 2.5 Ci slug of metallic Plutonium 238 (Pu-238). The radiation produced by the Pu-238 bombarded the walls of its container, producing heat that a thermopile then converted to an electrical current. A thermopile is a stack of thermocouples, which are devices that convert thermal energy directly into electrical energy using Seebeck effect. A thermocouple is made of two kinds of metal (or semiconductors) connected to each other in a closed loop. If the two junctions are at different temperatures, an electric current will flow in the loop. Continue reading