Telemonitoring in Patients with Heart Failure – Lessons from Recent Randomised Multicentre Trials
The second important study was published by Koehler et al. in 2011.7 This German multicentre study enrolled ambulatory patients who had stable disease. Their mean age was 67 years, the mean LVEF was 27 %, 50 % of patients had NYHA functional class III symptoms and more than 90 % were optimally treated with either angiotensin receptor blockers and β-blockers or angiotensin-converting enzyme inhibitors. The TLM system was very advanced, with direct bluetooth transmission of vital sign parameters to the core lab and a parallel system for handling emergency calls. Again, death and hospitalisation for HF were similar in the TLM and control groups. An analysis of the Kaplan–Meier curves shows that the percentage of patients who experienced cardiac events was only 10 %, versus 50 % in the US study by Chaudhry et al.,6 acute HF.
which enrolled patients admitted for
The trial was conducted in the UK, the Netherlands and Germany and enrolled patients 48 hours to six weeks after hospitalisation for acute HF. Eighty-five patients were randomised to a control group, 170 to a nurse-led monitoring system group and 163 to a TLM group. Patients in the TLM group had to transmit clinical parameters daily to the co-ordinating centre and, at the end of the study, compliance to this intensive programme was found to be quite low. A significant effect of TLM was demonstrated for cardiac death but not for HF hospitalisation. Similar to the US study,6 in the control group occurred in nearly 50 % of patients.
Two other European randomised multicentre studies have been published in recent years. In 2005, data from the Trans-European network home care management system (TEN-HMS) study were published.8
cardiac events
In 2009, Mortara et al. presented the results of the Home or hospital in heart failure (HHH) study.9
Patients with chronic HF were enrolled
during a stable phase of the disease in three European countries: Italy, Poland and the UK. The incidence of cardiac events at six months was 10 %, as in the German study,7
and again no differences
in the primary endpoints (cardiac death and HF hospitalisation) were observed between controls and the TLM group. Interestingly, when looking at the Italian arm of the study, which accounted for more than 50 % of the total study population, the TLM group exhibited a significantly lower number of cardiac events. This was explained by the extensive experience of Italian centres in the use of TLM and remote management of HF patients.
Why the Trials May Have Failed to Demonstrate Benefits from Telemonitoring
The main message of all these studies seems to be negative. Why did these trials fail to demonstrate any benefit from telemonitoring? Possible explanations are listed in Table 1. Of course, the obvious one is that TLM does not work and cannot have a positive effect on prognosis, whether after an acute event or in a chronic phase of the disease. However, this is not necessarily the case. Further explanations for these negative results are discussed below.
In these trials, the impression is that TLM has been used in the same way that a drug is tested in a randomised population (the drug is given and a positive or negative response is awaited during follow-up). None of them reported in any detail the interventions suggested by the core lab to address initial signs of decompensation, or the processes put in place to formulate recommendations for patients after reception of their clinical parameters. The telemedicine system should be supported by an expert in HF who knows the patients’ general disease
EUROPEAN CARDIOLOGY
Table 1: Possible Reasons Why the Recent Large Multicentre Trials Failed to Demonstrate Any Benefit From Home Telemonitoring in Heart Failure Patients
TLM does not really improve outcomes
In the study design, TLM was treated like a drug, when it is simply a way of improving communication
None of the trials reported data about the responses to alerts and the type of interventions put in place to solve the problems
The follow-up was very short (6–12 months) for multicentre studies using new technologies
The choice of physiological indicators was inadequate TLM relied mainly on patient-initiated communication, and this may have led to an underuse of the system (patients get bored with TLM, particularly if there is no adequate feedback)
TLM may be not effective if it is not integrated into an HF programme and if individualised alerting algorithms are not used
HF = heart failure; TLM = telemonitoring. Figure 1: Home or Hospital in Heart Failure (HHH) Study
0.6 0.7 0.8 0.9 1.0
0.5 02 4 6 Time (months)
All patients – control group All patients – TLM group
Italian patients – control group Italian patients – TLM group
p=0.080 p=0.016
Effect of telemonitoring (TLM) on mortality and heart failure hospitalisation in the whole study population and in the Italian arm of the HHH study. In the Italian centres, TLM was associated with a significant reduction in clinical events, probably because these centres had more experience of TLM and because TLM was more integrated with the HF clinic. Source: reproduced with permission from Mortara, et al., 2009.9
characteristics and co-morbidities. However, it is likely that, when centres enrolled patients shortly after an acute event, they did not have time to gather detailed information about these patients for correct home monitoring after discharge. Moreover, even when the team had extensive expertise in HF and knowledge of their patients, was it sufficiently prepared and organised to manage rapidly and efficiently a large flow of TLM data? Enrolling centres often become involved in such multicentre studies because of their experience of HF, not because they have a structured organisation that can handle large volumes of clinical data and actively manage information derived from these data. The HHH study may be considered a good example of this. Italian centres contributed to testing and ameliorating the TLM system used later on in the trial and, in the preceding pilot study, they had improved their abilities in telemonitoring and telemanagement. This expertise translated into a significant reduction in clinical events that was not observed to the same extent in the other participating European centres (see Figure 1). Thus it is time to design specific training courses in telemedicine and to establish new methods of compensation for all the personnel involved in complex clinical systems remotely caring for HF patients at home.
85 810 12
Italian TLM group
Italian control group
Cumulative event-free rate
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