Remote monitoring of pacemaker patients improves detection of
21 May 2008
Remote monitoring of pacemaker patients via the Medtronic CareLink
Network detected clinically actionable events (CAEs) more quickly than
routine follow-up care of transtelephonic monitoring (TTM) and in-office
visit, according to a study presented last week at the Heart Rhythm 2008
congress in San Francisco.
Medtronic Inc. (NYSE: MDT) sponsored the PREFER (Pacemaker Remote
Follow-up Evaluation and Review) trial, which was presented by Bruce
Wilkoff, MD, Director of Cardiac Pacing and Tachyarrhythmia Devices,
Department of Cardiovascular Medicine, Cleveland Clinic, and Professor
of Medicine at Cleveland Clinic Lerner College of Medicine, Case Western
“In the trial we found that by following patients through the
Medtronic CareLink Network every three months — and thus having
quarterly access to device diagnostics — clinicians are able to more
quickly identify the occurrence of clinically actionable events,” said
Dr. Wilkoff, principal investigator for PREFER.
For example, physicians who remotely monitored patients with the
Network more quickly detected new onset atrial fibrillation (AF) in
patients with no known history. Untreated AF — a rapid irregular
heartbeat in the upper chambers (atria) — can lead to stroke.
PREFER was a prospective, randomized, parallel, unblinded trial
involving 980 pacemaker patients at 50 centres in the United States. The
primary objective was to compare the rate of first diagnosis of CAEs
between patients who utilize the Medtronic CareLink Network (REMOTE arm)
versus patients who are followed via routine office visits augmented by
TTM (TTM arm). Secondary objectives were to characterize the frequency
of actions taken in response to CAEs, and to compare the rate of first
diagnosis of single types of CAEs. CAEs included physiologic changes
such as new onset atrial fibrillation (AF), uncontrolled ventricular
rate in AF, ventricular tachycardia, and device integrity alerts
affecting leads, pulse generators or batteries.
Patients in the REMOTE group had scheduled pacemaker interrogations
transmitted via the Medtronic CareLink Network at 3, 6, and 9 months
after enrollment, and an in-office evaluation at 12 months post-enrollment.
TTM patients with a dual-chamber devices transmitted 30-second EKG
strips at 2, 4, 6, 8 and 10 months after enrollment, with in-office
evaluations at 6 and 12 months. TTM patients with a single-chamber
pacemaker transmitted data via TTM instead of an in-office evaluation at
PREFER demonstrated that utilization of the Medtronic CareLink
Network resulted in a statistically significant improvement in the rate
of first diagnosis of clinically actionable events between the 602
patients in the REMOTE arm and the 295 patients in the TTM arm
(<0.0001). There were 272 patients in the REMOTE arm and 111 patients in
the TTM arm in which the investigator detected an event.
“Intuitively, one might think that increased frequency of information
as available via TTM would be beneficial in catching these clinically
actionable events,” said David M. Steinhaus, MD, vice president and
medical director of the Cardiac Rhythm Disease Management business at
Medtronic. “However, despite frequency, the limited point-in-time EKG
information provided by TTM didn’t uncover the potential for serious
cardiac events as early as the more comprehensive data provided for the
remote group. This has important implications for patient care by using
remote management systems such as the Medtronic CareLink Network.”
How it works
The Medtronic CareLink Network enables patients to transmit data from
their implantable device, as instructed by their physician, using a
portable monitor that is connected to a standard telephone line. Within
minutes, the patient’s physician and nurses can view the data on a
Available information includes arrhythmia episode reports and stored
electrograms along with device integrity information, which is
comparable to the information provided during an in-clinic device
follow-up visit, and provides the physician with a view of how the
device and patient’s heart are operating.
The system provides an efficient, safe and convenient way for
specialty physicians to optimize patient care by remotely monitoring the
condition of their patients and, if needed, make adjustments to
medication or prescribe additional therapy.
The Medtronic CareLink Network was introduces in the United States in
2002. Today, more than 250,000 patients at nearly 2,400 clinics in 20
countries are followed remotely, saving patients' time by eliminating
in-office visits, and allowing physicians to perform a complete analysis
of all the device- and patient-specific cardiac data stored within
Medtronic patients’ ICDs, pacemakers and CRT-D devices.
The Network has registered 1 million patient data transmissions since
the service’s inception.