Remote monitoring of patients with implantable cardiac devices reduced the mortality rate for cardiac patients by 50 percent and improved their clinical status by nearly 10 percent in a randomized control trial recently published in The Lancet. The trial was sponsored by medical device company Biotronik.
The trial was conducted at 36 different clinics and hospitals in Europe, Australia, and Israel and included a total of 664 patients. All patients had either implantable cardioverter-defibrillators (ICDs) or cardiac resynchronization therapy defibrillators (CRT-Ds) with telemonitoring functionality, but only one group used that functionality. An experiment group of 333 patients had readings from their device evaluated daily by medical personnel, while the remaining 331 formed a control group that received standard care with no telemonitoring. The mean age of all patients was 65.5.
According to the clinicaltrials.gov profile of the study: "During home monitoring surveillance, medical and technical data from an ICD or CRT device are sent to a modified mobile phone, the so-called Cardio Messenger. This device transmits the data via a mobile phone network to the Biotronik service center. There, the data are put into an easily accessible form and can then be viewed by the physician online via the internet on a secure website. Additionally, the occurrence of heart rhythm disturbances or device problems will be transmitted by fax, SMS or email."
After one year of monitoring, ten patients had died in the experiment group, versus 27 in the standard care group. In addition, according to a composite score encompassing death, hospitalization, NYHA class and patient self-assessment, 27.2 percent of the patients in the standard group (90 patients) had their heart condition worsen in the one year interval, compared with 18.9 percent of the telemedicine group (63 patients).
"Reducing mortality by over 50 percent is an excellent outcome for any therapy. [The study] showed how important automatic, daily transmissions of clinical and device data are to patient management and outcomes," Coordinating Investigator Dr. Gerhard Hindricks, from the University of Leipzig Heart Center in Germany, said in a statement. "Improvements in patients' health are likely due to the early detection of the onset or progression of ventricular and atrial tachyarrhythmias and the early recognition of therapy settings that may need adjusting."
These findings line up with a much larger study published in 2010 in the journal Circulation. That study, headed up by the Center for Body Computing's Dr. Leslie Saxon, followed 100,000 patients with implantable devices and also found that telemonitoring reduced mortality by 50 percent, though it looked at a 5-year rather than a 1-year follow-up period.
The Biotronik study also looked at the efficacy of the telemonitoring technology and infrastructure. They found that data was transmitted on 85 percent of patient days within the experiment group. In addition, they tracked the response time of the medical staff to an alert from the monitoring software. The median time was one day to patient contact and two days to follow-up.
"The effects of home monitoring depend on physicians' and medical staff's response to the remotely monitored data. By reacting quickly to notifications, we were able to follow up with patients exactly when they needed medical attention, and adapt their therapy accordingly," Dr. Peter Sogaard, one of the clinicians at the Aalborg University Hospital in Denmark, said in a statement. "We were also able to divide work between a qualified nurse and myself, the overseeing physician, to improve our clinic's workflow and ensure efficient patient management."