home telemonitoring for the management of heart failure
TRANSCRIPT
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TITLE: Home Telemonitoring for the Management of Heart Failure
AUTHOR: Jeffrey A. Tice, MD
Assistant Professor of Medicine
Division of General Internal Medicine
Department of Medicine
University of California San Francisco
PUBLISHER: California Technology Assessment Forum
DATE OF PUBLICATION: June 29, 2011
PLACE OF PUBLICATION: San Francisco, CA
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HOME TELEMONITORING FOR THE MANAGEMENT OF HEART FAILURE
A Technology Assessment
INTRODUCTION
The California Technology Assessment Forum (CTAF) was asked to assess the evidence for the use of
home telemonitoring devices for the management of heart failure (HF). HF is a common chronic disease
that is expensive to manage and subject to frequent episodes of decompensation requiring hospitalization.
There is an extensive literature on HF disease management programs, telephone support programs, and
home visiting programs that are intended to help patients and their physicians identify worsening heart
failure early and take corrective actions in order to avoid hospitalizations and improve patients’ quality of life.
Numerous companies have developed programs and medical devices intended to facilitate home monitoring
of patients with HF.
BACKGROUND
Heart failure (HF)
Heart failure (HF) is a major public health problem in the United States. Over five million patients in this
country have HF and 670,000 patients are diagnosed with HF for the first time each year.1 Nearly 300,000
patients die of HF as a primary or contributory cause each year. Survival has improved over time, but the
five-year mortality is still approximately 50%.1
The approach that is most commonly used to quantify the degree of functional limitation imposed by HF is
one first developed by the New York Heart Association (NYHA).2,3 This system assigns patients to one of
four functional classes, depending on the degree of effort needed to elicit symptoms: patients may have
symptoms of HF at rest (class IV), on less-than-ordinary exertion (class III), on ordinary exertion (class II), or
only at levels of exertion that would limit normal individuals (class I).
Medical therapies, such as angiotensin converting enzyme (ACE) inhibitors, beta blockers, and
spironolactone, have led to improvements in both symptom control and overall survival in patients with heart
failure.4 Implanted devices, such as biventricular pacemakers, also improve survival in appropriate
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patients.5,6
Despite recent advances in therapy, patients with HF suffer from repeat hospitalizations due to some
combination of the progression of their disease, poor adherence to diet and medical therapy, and limited
support.7-9 Because of the complexities of self-care and medical care involved in the optimal management of
HF, recent guidelines support a multidisciplinary care approach.10-12 Randomized trials have demonstrated
that nursing-led multidisciplinary teams focusing on patient and family education about diet and medications
combined with close follow-up reduces hospital readmission rates and overall healthcare costs while
improving quality of life for patients.13,14 Regular communication between patients with heart failure and their
care team is thought to improve outcomes for patients.
Home Telemonitoring Devices
Telemonitoring is defined by the transmission of physiologic parameters and symptoms from patients at
home to their health care provider. For HF, the parameters most frequently measured include the patient’s
weight, blood pressure, heart rate, oxygen saturation, and responses to questions about symptoms. In
addition, some devices allow transmission of either one or three lead ECGs for the evaluation of cardiac
rhythm, sounds via an electronic stethoscope, and videoconferencing. The goal is to facilitate frequent
measurement of these parameters in order to identify changes signaling heart failure decompensation
earlier than would have been possible without telemonitoring. Home telemonitoring might be a cost-efficient
approach to intensive follow-up of heart failure patients that reduces mortality, hospitalizations, and costs
while improving patients’ quality of life. Prior meta-analyses have suggested that home telemonitoring
reduces all-cause mortality and hospitalizations15,16, but the studies included in these and other meta-
analyses have been criticized for including many small, poor quality trials in which neither death nor
hospitalization was a primary outcome.17,18
TECHNOLOGY ASSESSMENT (TA)
TA Criterion 1: The technology must have final approval from the appropriate government
regulatory bodies.
Electronic monitoring systems used in disease management programs and/or in patient homes under the
guidance of a clinician are subject to regulatory oversight by the FDA and generally classified under Class II.
The FDA database was searched for the product codes for approved telemonitoring devices with the
following results: DRG (Transmitters and Receivers, Physiological Signal, Radiofrequency), DXN (System,
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Measurement, Blood-Pressure, Non-invasive), and MWI ((Monitor, Physiological, Patient [Without
Arrhythmia Detection or Alarms) with the following results:
DRG (Transmitters & Receivers, Physiological Signal, Radiofrequency): 112 products
DXN (System, Measurement, Blood Pressure, Non-invasive): 500 products
MWI (Monitor, Physiological, Patient (Without Arrhythmia Detection or Alarms): 144 products
The approved products feature capabilities relating to the collection and transmission of patient data to a
clinician for nonemergency review including blood pressure, weight, glucose monitoring, and oxygen
saturation.
TA Criterion 1 is met.
TA Criterion 2: The scientific evidence must permit conclusions concerning the effectiveness of
the technology regarding health outcomes.
The Medline database, Embase, Cochrane clinical trials database, Cochrane reviews database and the
Database of Abstracts of Reviews of Effects (DARE) were searched using the key words “telemonitoring,”
“telemonitor,” “remote patient monitoring,” “telemedicine,” “telehealth,” “telecare,” “telehomecare,”
“telecardiology,” or “remote physiological monitoring.” The results were crossed with the results from a
search on “heart failure” or “congestive heart failure.” The search was performed for the period from 1945
through May 2011. The bibliographies of systematic reviews15-25 and key articles were manually searched
for additional references. References were also solicited from the manufacturers and local experts. The
abstracts of citations were reviewed for relevance and all potentially relevant articles were reviewed in full.
This assessment focuses on the randomized comparisons between telemonitoring interventions and either
usual care or telephone support. This assessment includes only randomized trials of at least one hundred
patients with heart failure. This assessment excludes trials of telephone support alone that did not also
include a telemonitoring device and excludes studies that randomized patients without a diagnosis of heart
failure.
The search identified 917 potentially relevant studies (Figure 1). After elimination of duplicate and non-
relevant references including reviews and non-randomized studies the search identified 21 articles
describing 17 trials.26-46 Small trials, trials of mixed populations including patients without HF, non-
randomized trials, ongoing trials, and trials of telephone support without any home device were excluded.47-
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Figure 1: Selection of studies for inclusion in review
Level of Evidence: 1 through 5.
TA Criterion 2 is met.
TA Criterion 3: The technology must improve net health outcomes.
The most important outcomes for patients include mortality, the prevention of hospitalizations, and quality of
life. Patients with HF have a high mortality and are hospitalized frequently, so these outcomes were
routinely measured in the studies described below.
Randomized trials
Seventeen trials that randomized 6352 patients met the inclusion criteria for this assessment.26-46 The
quality of the trials is summarized in Table 1. Table 2 summarizes the characteristics of the studies including
a description of the telemonitoring intervention and the control group. Table 3 summarizes the main results
of the studies.
917 potentially relevant references screened
362 abstracts for assessment
21 studies included in assessment: 17 RCTs
67 studies for full text review
322 duplicate citations excluded 233 excluded: not randomized; reviews, abstracts only; other interventions
95 studies excluded (Editorials, reviews, abstracts, no
clinical outcomes)
46 studies excluded: not randomized, < 100 participants, no telemonitoring,
mixed population, ongoing study
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Table 1: Randomized trials of telemonitoring in patients with heart failure – Methodological Quality
Study Randomization Allocation
concealment
Groups comparable Outcome assessment
blinded
Follow-up >
80%
Intention to treat
analysis
Quality
2003 Benatar
Yes NR Yes NR Yes Yes Fair
2003 Goldberg
WHARF
Yes NR Yes Yes Yes Yes Fair
2004 Capomolla
Yes NR Yes NR NR Yes Fair
2005 Cleland
TEN-HMS
Yes Yes Yes NR Yes Yes Fair
2008 Balk
Yes Yes N, TM fewer HF
hospitalization,
p=0.001
NR NR Yes Poor
2008 Dansky
Yes, but baseline
differences in
group size
unexplained
Yes Yes Yes NR NR Poor
2008 Schwarz
Yes NR No, TM more
education: 82% vs.
49%
NR Yes Yes Poor
2008 Soran
HFHC
Yes NR Yes NR Yes Yes Fair
2009 Dar
Yes Yes Yes NR Yes Yes Good
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Study Randomization Allocation
concealment
Groups comparable Outcome assessment
blinded
Follow-up >
80%
Intention to treat
analysis
Quality
2009 Giordano
Yes NR N, TM more beta
blockers: 85% vs.
60%.
NR Yes Yes Fair
2009 Mortara
HHH
Yes Yes Yes Yes Yes Yes Good
2009 Scherr
MOBITEL
Yes NR Yes NR N Yes Fair
2010 Tompkins
Yes NR Yes NR Yes NR Poor
2010 Chaudhry
Tele HF
Yes NR Yes NR Yes Yes Good
2010 Piotrowicz
Yes Yes No, dropout 24% vs.
2.6%
NR No NR Poor
2010 Weintraub
PAN-CHF II
Yes Yes Yes NR Yes Yes Fair
2011 Koehler
TIM-HF
Yes Yes Yes NR Yes Yes Good
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Table 2: Randomized trials of telemonitoring in patients with heart failure - Study Characteristics
Study
N Location
# sites
Intervention Control Hospitalization
for inclusion?
NYHA
Class
EF for
inclusion
Adherence FU, mo 1° endpoint
2003 Benatar
216 United States
2
WT, BP, HR,
O2.
Daily
Home
Nurse 9-
12 visits
Yes, at
randomization
- - NR 3 NR
2003 Goldberg
WHARF
280 United States
18
WT, SX
Twice daily
UC Yes, at
randomization
III or IV ≤ 35% 98% 6 Any hospital
admission
2004 Capomolla
133 Italy
1
WT, SBP,
HR, SX
Daily
UC Yes, at
randomization
- - 81% 12 NR
2005 Cleland
TEN-HMS
426 UK, Germany,
Netherlands
16
WT, BP, HR,
ECG1.
Twice daily
TS 1/mo
Or UC
Yes, within 6
weeks
< 40% 81% 1/day
55% 2/day
8 Any hospital
admission or
death
2008 Balk
214 Netherlands
8
WT, BP, HR,
SX.
Daily
UC No - - NR NR NR
2008 Dansky
284 United States
10
WT, BP, HR
Daily
± video
Usual
homecare
NR - - NR 4 NR
2008 Schwarz
168 United States
1
WT, SX
Daily
UC Yes, at
randomization
II, III, or
IV
- 91% 3 Any hospital
admission
2008 Soran
HFHC
315 United States
3
WT, SX
Daily
UC Yes, within 6
months
- ≤ 40% 97% 6 HF hospital
admission or
death
2009 Dar
182 UK
3
WT, BP, HR,
O2, SX.
Daily
UC Yes, at
randomization
II, III, or
IV
- 95% 6 Any hospital
admission
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Study
N Location
# sites
Intervention Control Hospitalization
for inclusion?
NYHA
Class
EF for
inclusion
Adherence FU, mo 1° endpoint
2009 Giordano
460 Italy
5
ECG1 + TS
Weekly
UC Yes, at
randomization
+ 1 prior
II, III, or
IV
< 40% NR 12 Any hospital
admission
2009 Mortara
HHH
461 Poland, UK,
Italy
11
WT, SBP,
HR, SX
Daily
TS
monthly
No II, III, or
IV
≤ 40% 81 to 92% 12 HF hospital
admission
2009 Scherr
MOBITEL
120 Austria
8
WT, BP, HR.
Daily
UC Yes, within 4
weeks
- - 95% 6 Any hospital
admission or
death
2010 Tompkins
390 United States
1 health plan
WT, BP, HR,
O2.
Daily
UC No - - NR 6 NR
2010 Chaudhry
Tele HF
1653 United States
33
WT, SX
Daily
UC Yes, within 30
days
- - 90% week 1
55% week
52
6 Any hospital
admission or
death
2010 Piotrowicz
152 Poland
1
ECG3, SX
Daily
UC with
cardiac
rehab
Yes, at
randomization
II or III ≤ 40% NR 2 NR
2010 Weintraub
SPAN-CHF II
188 United States
4
WT, BP, HR,
SX.
Daily
TS Yes, within 2
weeks
- - NR 3 HF hospital
admission
2011 Koehler
TIM-HF
710 Germany
165
WT, BP, HR,
ECG1.
Daily
UC No II or III ≤ 35% 81% 26 Death
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Table 3: Randomized trials of telemonitoring in patients with heart failure - Study outcomes
Study TM, n
Control, n
CVD Hosp, % Any Hosp, % Death, % Quality of life HF Hosp, % Any Hosp or
Death, %
Other
2003 Benatar
108
108
NR
NR
NR
NR
NR
NR
52
58
p=.47, MLHF
12%
22%
p<.001
NR
NR
Difference in HF
hospitalization
NS at 12 months
2003 Goldberg
WHARF
138
142
8%
12%
p=.28
19%
20%
p=.28
8%
18%
p=.003
-28
-23
p=.22 MLHF
NR
NR
~54%
~62%
p NS at 180 days
2004 Capomolla
67
66
NR
NR
NR
NR
7%
11%
p NR
NR
NR
NR
NR
36%
68%
p NR
Total event count
lower in TM
group (32 versus
103, p<.001)
2005 Cleland
TEN-HMS
168 TM
173 TS
85 UC
NR
NR
NR
47%
49%
54%
p NR
17%
16%
24%*
NR
NR
NR
25%
20%
28%
p NR
51%
54%
56%
p NR
NS differences in
days lost to
hospitalization or
death
2008 Balk
101
113
NR
NR
NR at the
patient level.
Total n TM
103 vs. UC 96,
p NR
9%
7%
p NR
P for difference > .6
on SF36 and MLHF
NR
NR
9.4
7.0
p=.29
Days in hospital
2008 Dansky
45 TM+V
127 TM
85 UC
NR
NR
NR
36%
38%
40%
p NS
Not significant,
results NR
Not significant,
results NR
NR
NR
NR
NR
NR
NR
2008 Schwarz
51
51
NR
NR
32%
33%
p=.90
8%
14%
p NR
27
27
p=.98 MLHF
NR
NR
NR
NR
-
2008 Soran
HFHC
160
155
NR
NR
47%
42%
p=.44
7%
11%
p=.24
NR
NR
19%
24%
p=.31
48%
46%
p=.66
-
2009 Dar
91
91
NR
NR
36%
25%
p=.30
NR
NR
p>.50 for MLHF
and EQ5D
19%
11%
p=.01
NR
NR
-
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Study TM, n
Control, n
CVD Hosp, % Any Hosp, % Death, % Quality of life HF Hosp, % Any Hosp or
Death, %
Other
2009 Giordano
230
230
24%
36%
p=.006
29%
42%
p=.03
9%
14%
p NR
NR
NR
19%
32%
p=.001
NR
NR
-
2009 Mortara
HHH
101 TS+V+ECG
94 TS+V
106 TS
160 UC
NR
NR
NR
NR
30%
35%
36%
35%
NR
NR
NR
NR
NR
NR
NR
NR
18%
17%
18%
18%
NR
NR
NR
NR
-
2009 Scherr
MOBITEL
66
54
NR
NR
17%
31%
0%
2%
p NR
NR
NR
NR
NR
17%
33%
p=.06
2010 Tompkins
193
197
NR
NR
IRR 0.87
P NS
No CI given
NR
NR
NR
NR
NR
NR
NR
NR
IRR for urgent
care visits 1.60
p<.01
2010 Chaudhry
Tele HF
826
827
NR
NR
49%
47%
p=.45
11%
11%
p=.88
NR
NR
27%
27%
p=.81
52%
51%
p=.75
-
2010 Piotrowicz
77
75
NR
NR
NR
NR
NR
NR
70
69
p NS, SF36
NR
NR
NR
NR
-
2010 Weintraub
PAN-CHF II
95
93
NR
NR
54%
53%
p=.30
1%
4%
p=.21
NR
NR
13%
32%
p=.05
NR
NR
2011 Koehler
TIM-HF
354
356
28%
26%
p=.58
44%
39%
p=.29
15%
15%
p=.87
54
52
p=.30 for SF36
physical functioning
at 24 months
11%
13%
p=.32
NR
NR
15%
17%
p=.44 for HF
hospitalization or
death
*Comparisons at 240 days not analyzed statistically, but by Kaplan Meier rank sum test, the telemonitoring and telephone support groups did not differ; the usual care group had
significantly worse overall mortality than the other two arms (p=.04).
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Most of the studies were of overall fair to good quality. Most did not describe any allocation concealment
and blinding of the outcome assessment was rarely reported. It was not possible to blind the study
participants, but the most important outcomes, mortality and hospital admission, were objective and less
likely to be biased because patients knew their treatment assignment. Subjective outcomes, such as quality
of life questionnaires are more likely to have biased results due to the lack of participant blinding.
There was significant heterogeneity in the studies themselves. Almost all of the studies used different
devices and measures as part of the telemonitoring intervention. Some had participants take measurements
twice a day and others once a day. Most, but not all studies, measured weight and symptoms, but the
symptom questions differed between studies. Other measures included blood pressure and heart rate
(65%), ECG (24%), oxygen saturation (18%), and video monitoring (6%). Seven of the trials required
patients to have a reduced ejection fraction (most commonly ≤ 35%). Twelve of the trials required patients
to have had a recent hospitalization and seven trials randomized patients as they were being discharged
from the hospital. Follow-up varied from three to twenty-six months with only three trials reporting one year
outcomes and only one trial reporting outcomes beyond one year. Mortality varied from 2% to 24% in the
control arm of the trials, highlighting the variability in the patient populations studied. Mortality was nominally
lower in the telemonitoring (TM) group in seven trials, but was at least as high as that of the control group in
4 of the trials. Six trials did not report their mortality data. Similarly, the rate of hospitalization was lower in
the TM group in eight trials, but higher in six trials. Because of significant heterogeneity, no meta-analysis
was performed. The three largest studies impacting clinical practice are described in detail below.
Trans-European Network Home Care Management System (TEN-HMS) Study
The Trans-European Network Home Care Management System (TEN-HMS) study was the first large,
multicenter randomized trial to evaluate home telemonitoring for HF.31 The study was implemented at 16
hospitals in the United Kingdom, Germany and the Netherlands. These centers were chosen because they
lacked a comprehensive heart failure management program. The study randomized patients hospitalized for
heart failure as well as those hospitalized in the six weeks prior to randomization. All patients had an
ejection fraction ≤ 40% and were taking at least 40 mg of furosemide or an equivalent loop diuretic dose.
The study randomized participants in a 2:2:1 ratio to telemonitoring (TM), telephone support (TS), or usual
care (UC). Telemonitoring included twice-daily measurement of weight, blood pressure, heart rate, and
single lead ECG rhythm. All measures were electronically transmitted to study centers without patients
calling or typing in any of the information. Significant changes in any of the measurements triggered nursing
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review of the data and either counseling of patients or medication changes. Patient in the TM group also
received the same telephone support as patient in the TS group. Patients randomized to the telephone
support group received a monthly phone call from a nurse who specialized in heart failure care. They were
also given a number to call to reach the nurse-specialist, though in emergencies they were instructed to call
their primary care provider or the ambulance service. The primary outcome of the study was unusual: days
lost due to hospitalization or death during 450 days of follow-up. Symptoms and all-cause mortality were
secondary outcomes.
The study planned to randomize 500 patients, but it was stopped early by the data safety and monitoring
committee because of excess deaths in the usual care group.31 At that time only 426 patients had been
randomized and follow-up only allowed evaluation of the primary outcome through 240 days in most
patients. Baseline characteristics differed somewhat across the three groups and no statement was made
that the characteristics were similar across groups. No p-values were reported for baseline comparisons.
Examples of characteristics with large differences included the percentage of women in each group (20%
TM, 28% TS, 18% UC), the percentage with prior heart attacks (56% TM, 52% TS, 67% UC), the
percentage with EF < 25% (48% TM, 50% TS, 57% UC), and the median brain natriuretic protein (BNP)
level (3873 TM, 2909 TS, 2309 UC). The last is almost certainly statistically significant, but would tend to
bias the outcomes in favor of the UC group and against the TM group because a higher BNP level is
associated with more severe heart failure. During a median of 484 days of follow-up, only four patients were
lost to follow-up and an additional 12 did not comply with home telemonitoring. Only 64% of the randomized
patients had data available for the originally planned 450 day analysis.
At 240 days, there were no statistically significant differences between any of the groups in the primary
outcome of days lost to death or hospitalization.31 There was a trend towards 8 fewer days lost in the TM
group compared to the TS group and an additional 8 fewer days lost comparing TS to UC. In the subset of
patient with data for the primary outcome at 450 days (64% of randomized patients), both the TM and TS
groups had lost significantly fewer days compared to the UC group. The difference between the TM and TS
group was not significant, but favored the TS group by 6 days. The p-value for differences in mortality was
not calculated at any time point, but was consistently lowest in the TS group and highest in the UC group
(240 days TM 17%, TS 16%, UC 24%; 450 days TM 34%, TS 31%, UC 51%; overall in study TM 22%, TS
20%, UC 33%).
In the TEN-HMS study, telemonitoring reduced mortality compared to usual care.31 However twice daily
monitoring of five parameters (weight, systolic and diastolic blood pressure, heart rate, and rhythm)
transmitted without patient input was no more effective than monthly telephone support from a nurse that
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included nursing availability for patient-initiated calls. Mortality was nominally lower in the telephone support
group (20.3% versus 21.8%). There was a trend towards fewer days lost to hospitalization or death with TM
at 240 days, but this trend was reversed by 450 days. Thus, intensive home telemonitoring that required
minimal patient involvement failed to benefit patients any more than monthly telephone support from trained
nurses in this study population. Both telemonitoring and telephone support tended to produce better
outcomes than usual care.
Telemonitoring to Improve Heart Failure Outcomes (Tele-HF)
The Tele-HF study is the largest randomized trial of home telemonitoring that has been published to
date.29,30 The study randomized 1653 patients from 33 cardiology practices in the United States to either
home telemonitoring or usual care. Home telemonitoring required the patients to call a toll free number once
daily and answer five questions on heart failure symptoms, two questions on their general health, and input
their weight. A two-question depression scale was completed monthly. Any new heart failure symptoms,
depression, or a three-pound change in weight generated a message to the patient’s clinical site. Staff at the
site were required to call the patient to discuss the symptoms or weight change and to document treatment
decisions flowing from these calls. The primary endpoint of the study was any death or hospitalization within
180 days of randomization.
There were no significant differences between the two groups at baseline.30 The participants’ median age
was 61 years, 42% were female, and 39% were black. Follow-up was 100% for the primary outcome. There
were no differences between the two groups in all cause mortality (11.1% versus 11.4%, p=0.88),
hospitalization (49% versus 47%, p=0.45), HF hospitalization (27% versus 27%, p=0.81), days in the
hospital (7.2 versus 7.0, p=0.27), or the primary outcome: death or any hospitalization (52.3% versus
51.5%, p=0.75) with only the trend in deaths favoring the telemonitoring arm. Using survival analysis, the
primary outcome was slightly more common in the telemonitoring group (HR 1.04, 95% CI 0.91 to 1.19). In
six reported subgroup analyses, there were significant interactions with sex and NYHA class. Women
tended to benefit more than men (HR 0.87 versus 1.18, p for interaction = 0.02) and patients in NYHA Class
I or II tended to do better than those in Class III or IV (HR 0.88 versus 1.15, p for interaction = 0.05). There
were no significant interactions with age, race, ejection fraction, or site enrollment.
The results from the Tele-HF study30 contrast with those from the TEN-HMS study31 described above. In the
Tele-HF study, there was absolutely no benefit in the telemonitoring group compared to the usual care
group. The authors speculate that it may be the lack of regular communication with a provider that explains
15
the negative results of this study. In a prior, small trial, the same investigators found a 44% reduction in
readmission rates in patients with HF who were randomized to an intervention consisting of education and
support.13 The intervention also required more of the patients as they were required to enter their weight into
the system via the telephone, while the telemonitoring system used in TEN-HMS simply required the patient
to get on the scale twice a day: the data was automatically transmitted. The system was underused – 16%
of patients randomized to telemonitoring never used the system and by the last week of the study, only 55%
of the patients were using the system three times a week or more. However, even if only half of the patients
were using the system regularly, some trends towards improved outcomes should have been observed if
the system was effective. No such trends were observed.
Telemedical Interventional Monitoring in Heart Failure (TIM-HF) trial
The most recent, large randomized trial to be published was the TIM-HF trial.36,37 The study randomized 710
patients from 165 cardiology, internal medicine, or general medicine practices in Europe to either home
telemonitoring or usual care. Home telemonitoring consisted of once daily wireless, automatic transmission
of weight, blood pressure, heart rate, and 3-lead ECG data via a wireless personal digital assistant (PDA) to
the telemedical center. Daily health status was assessed using the PDA. In addition, patients randomized to
the TM group received a personal emergency response system that connected the patient to a physican at
the telemedical center in cases of emergency. This system also allowed for live ECG monitoring and oxygen
saturation monitoring. The primary endpoint of the study was all-cause mortality.
There were no significant differences between the groups at baseline. The participants’ average age was 67
years, 21% were female, 50% had NYHA Class III symptoms, and their average EF was 27%. Follow-up
was 99.7% complete for the primary outcome through a median follow-up of 26 months. There were no
differences between the two groups in all cause mortality (TM 15% or 8.43 per 100 person-years versus UC
15% or 8.68 per 100 person years; HR 0.97, 95% CI 0.67 to 1.41, p=0.87). In addition to the primary
outcome, there were no significant differences between the two groups for cardiovascular mortality,
hospitalization, hospitalization for cardiovascular disease, hospitalization for HF, change in NYHA class or
symptoms of depression. The SF-36 physical functioning subscale was higher at the one-year follow-up in
the TM group (54.3 versus 49.9, p=0.01), but the difference was no longer significant at two years (53.8
versus 51.7, p=0.30).
In contrast to the Tele-HF study, the TIM-HF study automated the transfer of the measured parameters and
included blood pressure, heart rate, and a 3-lead ECG tracing in addition to weight. Despite the inclusion of
16
these additional measures, better compliance (81% of patients completed at least 70% of the daily
measures), and longer follow-up, the use of TM did not reduce mortality or hospitalizations.
Summary
Despite initial promise, recent studies of a variety of approaches to home telemonitoring have failed to
demonstrate significant benefits when used in patients with heart failure. There was significant
heterogeneity in the early trials. The TEN-HMS trial found that telemonitoring was equivalent to monthly
telephone support by a trained nurse.31 The two most recent trials (Tele-HF, TIM-HF) meet the current
standards for high quality care of patients with HF and were the largest and highest quality trials
reviewed.30,36 The results from both studies were definitively negative. Neither study had any important
trends towards a reduction in either mortality or hospitalization for the telemonitoring group.
TA Criterion 3 is not met.
TA Criterion 4: The technology must be as beneficial as any established alternatives.
The management of HF is complex, particularly for patients with advanced disease. A wealth of large, high
quality randomized trials have demonstrated that a number of drugs and devices increase long-term survival
for patients with heart failure. In addition, multi-disciplinary team care focusing on patient and family
education and close follow-up reduces repeat hospitalizations and improves the quality of life for patients
hospitalized for worsening heart failure. The two largest randomized trials failed to demonstrate any
additional improvements with the addition of home telemonitoring to high quality usual care.30,36 The earlier
TEN-HMS trial did find benefits from telemonitoring, but only in patients treated at centers without an
organized heart failure management program and telemonitoring in this trial was no better than monthly
calls from a nurse.
TA Criterion 4 is not met.
TA Criterion 5: The improvement must be attainable outside of the investigational setting.
There are a wide variety of telemonitoring systems used in clinical practice across the world. They are
designed to be easy for patients to use. However, they do require that systems and personnel be trained
17
and available to rapidly respond to any of the measured parameters that suggest worsening of heart failure.
The published multicenter randomized trials as well as the many observational studies suggest that the
logistics of telemonitoring are feasible outside of the investigational setting. However, the published data
have not demonstrated significant improvements in net health outcomes, so TA criterion 5 is not met.
TA Criterion 5 is not met.
CONCLUSION
Heart failure is very common, progressive disease with frequent decompensation resulting in hospitalization
and death. Approximately half of people diagnosed with heart failure die within five years of the diagnosis.
When patients are discharged from hospitalization for heart failure up to 25% are readmitted within one
month and 50% are readmitted within six months. Patient and family education about medications, diet, and
heart failure combined with frequent follow-up has been shown to significantly reduce readmission and
death following hospitalizations for heart failure. Home telemonitoring of signs and symptoms associated
with heart failure is a promising approach to intensive follow-up of patients that places fewer demands on
patients by decreasing the need for clinic visits and on fewer demands on nursing staff by reducing the need
to travel for home visits.
This systematic review of the literature identified 17 trials that randomized 6352 patients to evaluate the
efficacy of home telemonitoring. The settings, patient populations, interventions, control groups, outcomes
and length of follow-up varied widely between the studies. Because of the heterogeneity in the trials and
their outcomes, no formal meta-analysis was performed. Two large, high quality trials that randomized 2363
patients were published in the past year (Tele-HF, TIM-HF). One used a simple intervention to capture
weight and symptoms once a day using an automated telephone-based system. The second measured
similar parameters and added daily blood pressure, heart rate, and ECG measures along with an
emergency link to center physicians. Neither study found any benefit to home monitoring compared with
usual care. Mortality was 11% in both groups in one study and 15% in both groups in the other study. In
both studies, hospitalization rates were slightly higher in the home telemonitoring groups (Tele-HF 49%
versus 47%; TIM-HF 44% versus 39%). Thus, there were not even trends in favor of home telemonitoring.
There are at least two additional large studies that have yet to be published (TEHAF, OptiLink-HF), but
preliminary results from one of the studies were negative. The strongly positive findings in some of the
randomized trials suggest that there are subgroups of patients with HF who benefit from some form of
telemonitoring. However, the published literature to date does not clearly identify which patients are most
18
likely to benefit and what combination of home monitoring technologies are required to obtain optimal
results. Newer, more invasive devices that monitor intracardiac or pulmonary artery pressure are on the
horizon and preliminary studies suggest that some of them may reduce heart failure hospitalizations in
patients with HF.
RECOMMENDATION
It is recommended that use of home telemonitoring for patients with heart failure does not meet CTAF TA
Criterion 3 through 5 for safety, effectiveness and improvement in health outcomes.
The California Technology Assessment Forum panel voted to accept the recommendation as
written.
June 29, 2011
This is the first review of this technology by the California Technology Assessment Forum
19
RECOMMENDATIONS OF OTHERS
Blue Cross Blue Shield Association (BCBSA)
The BCBSA Technology Evaluation Center has not conducted an assessment of home telemonitoring for
heart failure patients.
Centers for Medicare and Medicaid Services (CMS)
CMS does not have a national coverage code (NCD) for remote monitoring or telemonitoring.
American Telemedicine Association
The American Telemedicine Association did not provide an opinion regarding the use of this technology and
no representative provided testimony at the meeting.
American College of Cardiology/American Heart Association (ACC/AHA)
ACC/AHA 2009 Focused Update on “Guidelines for the Diagnosis and Management of Chronic Heart
Failure in the Adult” did not mention remote monitoring.
National Institute for Clinical Health and Excellence (NICE)
The NICE guideline, “Management of chronic heart failure in adulst in primary and secondary care” from
August 2010 stated that further research is required to determine whether monitoring has advantages over
specialized multidisciplinary heart failure teams.
Heart Failure Society of America (HFSA)
The Executive Summary: HFSA 2010 Comprehensive Heart Failure Practice Guideline mentions
telemonitoring within the context of disease management programs studies and care delivered in the home.
No specific guideline for telemonitoring was mentioned.
European Society of Cardiology (ESC)
The ESC Guidelines for the management and treatment of acute and chronic heart failure 2008 mentions
remote management as an emerging field in HF management programs such as telephone support and the
use of telemonitoring equipment. Telemonitoring equipment installed at the patient’s home typically capture
and record heart rate, ECG, oxygen saturation, weight, medication adherence, and blood pressure.
However, there is no consensus on which factors should be monitored.
20
ABBREVIATIONS
CTAF California Technology Assessment Forum
DARE Database of Abstracts of Reviews of Effects
RCT Randomized Controlled Trial
NR Not reported
NS Not significant
RR Relative Risk
CI Confidence Interval
NNT Number needed to treat
IRR Incidence rate ratio
HF Heart failure
TM Telemonitoring
TS Telephone support
UC Usual Care
FU Follow-up
NYHA New York Heart Association
WT Weight
BP Blood pressure
SBP Systolic blood pressure
HR Heart rate
SX Symptoms
21
02 Oxygen saturation
ECG Electrocardiogram
ECG1 Electrocardiogram, one lead
ECG3 Electrocardiogram, three leads
EF Ejection Fraction
CVD Cardiovascular disease
Hosp Hospitalization
MLHF Minnesota Living with Heart Failure Questionnaire: quality of life in heart failure
EQ5D EuroQOL 5D: a standard quality of life questionnaire
SF36 Short Form 36: a standard quality of life questionnaire
Study names
WHARF Weight Monitoring in Heart Failure
TEN-HMS Trans-European Network Home Care Management System
HHH Home or Hospital in Heart failure
MOBITEL MOBIle TELemonitoring in Heart Failure Patients
Tele-HF Telemedical Interventional Monitoring in Heart Failure
SPAN-CHF II Specialized Primary and Networked Care in Heart Failure II
TIM-HF Telemedical Interventional Monitoring in Heart Failure
22
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