Tiny implanted monitors, 'black boxes' for humans, gain traction
miami.com
EVAN RAMSTAD
Associated Press
Posted on Sun, Dec. 01, 2002
ARDEN HILLS, Minn. - Data recording devices in airplanes, the so-called black boxes, describe what when wrong after a disaster. Now, medical devices are emerging to act like a black box in the human body, except they're being used to prevent disaster.
Though still in an early stage, a market is growing for implantable monitors, tiny devices that track a person's innards.
Medtronic Inc. five years ago released its first implantable monitor, for people with mysterious fainting spells. Though a niche product for the giant maker of pacemakers and defibrillators, it was a breakthrough, giving doctors far more data about what's happening to a person's heart when they faint.
Two product generations later, Medtronic has sold more than 25,000 of the 2-inch-long monitors that weigh just a few grams. They're placed in a person's pectoral muscle, sometimes for as little as a few days, and keep track of heart activity in a 42-minute loop.
When a person recovers from a fainting incident, he or she holds a small device over the monitor to stop it from recording over data of the event. Then, the person goes to the doctor's office, where a doctor or nurse can retrieve the data with a special radio receiver and restart the loop.
Immediately after the device hit the market, the quality of diagnosis for people with infrequent fainting spells shot up. Often, doctors can tell from the data whether something more serious is occurring with the heart. In some cases, people diagnosed with epilepsy turned out to suffer from heart problems.
"A lot of the pull for the device came from patients, people who were frustrated, weren't able to drive, in disarray because fainting messed up their lives," said Brian Lee, a co-inventor of the device, which Medtronic calls Reveal.
The device is just the start for monitors in the body. As wireless technology and the Internet advanced, a technical structure grew that allowed makers of other implanted devices, such as pacemakers and defibrillators, to add monitoring features. Medtronic and rival Biotronik Inc. in the past year began selling such products.
The theoretical hope: with people living longer and a demographic bulge of Baby Boomers hitting old age in the next two decades, implantable monitors will help doctors keep track of patients and treat them for less cost with fewer visits to hospitals.
To date, Medtronic's Reveal remains unique as an implanted device that performs only a diagnostic function. But that will change.
"Theoretically speaking, you can record many other things, such as blood pressure, blood sugar," says George Klein, the Canadian doctor who first approached Medtronic about developing the fainting monitor in the late 1980s. "You've got a little device that's monitoring all kinds of biochemical and physiological information that can be transmitted to a medical center or to other devices in the body."
For Data Sciences International Inc., a small company five miles from Medtronic's headquarters in this Minneapolis suburb, the rise of the implantable monitor market is an opportunity for major growth. The company since the mid-1980s produced implantable monitors used to keep track of blood pressure, heart rate and other conditions in laboratory animals, improving the research capabilities of scientists in many fields.
After an infusion of venture capital this spring, Data Sciences is gearing up for its first foray into the human clinical market. It's racing with Medtronic to produce monitors that will keep track of blood pressure inside the heart itself, a device aimed at heart failure patients.
Data Sciences made several false starts in the 1990s with implantable monitors for people. "There were times when I questioned whether the medical community would embrace this in my lifetime," said Brian Brockway, president and chief executive officer.
To many doctors, implanted devices represented a last resort in patient treatment. Few believed they should be used for diagnosis, preferring to implant only devices that correct problems, as pacemakers and defibrillators do.
But the success of Medtronic's Reveal, coupled with rising costs of health care and demographic pressures, forced doctors to re-evaluate.
In addition to spotting the change in doctors' attitudes, Data Sciences made progress with pressure-sensing and packaging technologies. Traditionally, implanted devices like pacemakers were packaged in titanium. Data Sciences will rely on new ceramic material.
Its first product will have a base station in the home that periodically reads the radio signal sent from the implanted blood pressure monitor. The data will then be sent to the patient's doctor via the Internet.
Medtronic's competing product, called Chronicle, works in a similar fashion and is already undergoing early testing. Brockway believes Data Sciences' first implantable monitor, though likely to roll out after Chronicle, will leapfrog the Medtronic device.
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Evan Ramstad may be reached at eramstad(at)ap.org. |
