When Medtronic (MDT) began selling the first internal pacemakers in 1960, the cardiac devices were little more than metronomes, discharging electrical pulses at a constant rate. These days, implanted electronic devices are interactive marvels that can adroitly adjust their output based on signals picked up from the patient's body. Some can even beam this information automatically to external monitors.
But as sophisticated as they are, today's pacemakers and defibrillators may come to be regarded as relics in the next few years. Medtronic, for example, is awaiting government approval of an implant that can measure pressure inside the heart's chambers beat by beat. The idea is to detect the onset of heart failure before the patient notices any symptoms. Further out, the $10 billion company is experimenting with devices that could instruct an implanted pump to administer drugs when they sense trouble.
Meantime, St. Jude Medical Inc. (STJ) will be rolling out products over the next several months that can record more cardiac data and then relay the information at higher speeds wirelessly. The company has also developed wires and leads that are no larger than the ink tube in a ballpoint pen. Today, surgeons can install a cardiac device in as little as 20 minutes in a patient under local anesthesia. Miniaturization could make the operation even faster.
"It's really an amazing revolution," says Dr. David M. Steinhaus, medical director of cardiac rhythm management at Minneapolis-based Medtronic. "This is such an exciting time."
NOISE FILTERS. The progress may seem as inexorable as Moore's Law. In fact, many of these breakthroughs are due to the doubling of computing power for the same price roughly every 18 months, which enables device manufacturers -- Medtronic, St. Jude, and Guidant Corp. (GDT) -- to pack much more capability into a hermetically sealed titanium canister the size of a stopwatch.
Still, it's hard work. The heart is constantly sending out myriad electrical signals so it takes insightful software to pick out the meaningful message from the static. Transmitting data outside the body through radio waves also consumes power. That means engineers must find ways to extend battery life or the implanted products won't last as long. Then there are market forces to overcome. Unless manufacturers can show that their expensive new gizmos will lower overall health-care bills -- say, by averting lengthy hospital stays -- no one will pay for them no matter how cool the technology is.
Medical-device producers see the biggest advances in two areas. One is enabling the implants to do more diagnostics. Today defibrillators can detect when a heart's rhythm has gone awry by monitoring its signals and then send out a choreographed pattern of jolts to restore its natural beating pattern.
LUNG LOOKOUT. Market leader Medtronic has implants that can go further. Its Sentry defibrillator can watch out for a buildup of fluids in the lungs, an early warning sign of congestive heart failure. The next iteration is the Chronicle, which Medtronic could start selling in late 2006. Designed specifically as a heart-failure monitor, it works by checking pressure inside the heart -- another yellow light that the organ is giving out -- as well as body temperature and heart rate through a single wire to the right ventricle. St. Jude is in clinical trials with a similar device, the HeartPOD, which probes the left atrium.
By the end of the decade, electronic-device manufacturers say their implants should be able to track many more vital signs. This is important because most heart patients have other serious ailments on top of heart disease. As sensors become more refined and implants learn to communicate with one another, the next step will be linking devices within the body. For example, an implant might sense when a patient's blood levels are out of whack and tell a drug pump to inject a dose of corrective medicine. "The device will be smart enough to identify before patients become symptomatic, that they're starting to go down a bad path," says Michael J. Coyle, president of the Cardiac Rhythm Management Div. at St. Jude, based in St. Paul, Minn.
The second advance complements the first: sharing all of these readings with doctors or clinicians so they can modify prescriptions or therapies if something is going wrong. The latest devices all allow medical personnel to "interrogate" them, by placing a wand-like receiver over the patient's chest that prompts the implant to beam out data. Medtronic has a system called CareLink that lets patients do this at home, too. The information is sent over a telephone line to a secure Web site at a monitoring service. Almost 60,000 patients and 750 clinics are enrolled in this program today.
VIBE ALERT. The limitation, of course, is that doctors get the patient stats only if someone picks up the wand and asks for them. To get around this, Indianapolis-based Guidant has just begun selling equipment to take readings automatically. Its Contak defibrillator can communicate wirelessly with its Latitude in-home monitor up to eight feet away at preset times. Medtronic is testing a similar product on patients in a clinical trial.
In early February, St. Jude introduced Victory, a pacemaker that takes daily readings of a heart's behavior and can wirelessly upload the data at high speeds to a programmer in a doctor's exam room. By midyear, the $2.9 billion company also plans to market devices that will vibrate like a mobile phone in a patient's chest whenever they sense trouble. "All of this is really automating the process," says Coyle. "At the next level, you don't want the patient to have to do anything."
Heart disease is the No. 1 killer in the U.S., and some 225,000 Americans will receive a cardiac device this year alone. With the Baby Boom generation set to swell the ranks of the elderly, smarter implants could hardly come at a better time.