Ambulatory ECG Monitoring for Syncope and Collapse: A Comparative Assessment of Clinical Practice

in UK and Germany.

Short title: Ambulatory ECG for syncope

Richard Sutton DSc MB BS (a),Robin Mears MBA (b),

Ritsuko Kohno MD PhD (c)David Benditt MD (c)

From the Cardiology Department, National Heart & Lung Institute, Imperial College,

London, UK (a); Medtronic Inc., Minneapolis, Minnesota, USA (b) and the Cardiac

Arrhythmia Center, Cardiovascular Division, University of Minnesota Medical School,

Minneapolis Minnesota, USA (c).

Corresponding author:Emeritus Professor Richard Sutton

Cardiology Department

Hammersmith Hospital

Ducane Road

London W12 0NN

United Kingdom

Tel: +44 20 7594 5735

Email: r.sutton@imperial.ac.uk

Dr Benditt is supported in part by a grant from the Dr Earl E Bakken Family in support of

Heart-Brain research.

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Potential Conflicts of InterestDr Sutton is a consultant to Medtronic Inc., serves on a Speaker’s bureau for St Jude

Medical Inc. (Abbott Laboratories Inc.) and holds equity in Boston Scientific Inc. and

Edwards LifeSciences Corp.

Robin Mears is a Medtronic employee and holds equity in Medtronic Inc.

Dr Benditt is a consultant to and holds equity in Medtronic Inc, and St Jude Medical

(Abbott Laboratories Inc.)

Author ContributionsRichard Sutton: Manuscript concept, critical data review and manuscript revisions;

Robin Mears: Data acquisition, Figure development, manuscript revisions

Ritsuko Kohno: Manuscript review as an ICM expert and text revisions

David G Benditt: Manuscript concept, critical data review and manuscript revisions.

Key AbbreviationsAECG: Ambulatory electrocardiogram

ED: Emergency department

ICM: Insertable cardiac monitor (up to 3 years of recording) previously known as

Insertable/implantable loop recorder.

ELR: External Event Recorder: Wearable monitor (usually 2 weeks to 1 month)

PCP: Primary care practitioner (provider)

TLOC: Transient loss of consciousness.

HCP: Health care practitioner

What’s New- The following of Syncope Guidelines for selection of diagnostic ambulatory ECG

devices is presently unclear

- A survey of the practice of Emergency physicians and Cardiologists in UK and

Germany has been undertaken

- Most UK and German practitioners closely follow local or European Guidelines but

a substantial minority diverges from them in use of Insertable cardiac monitors and

selection of a second monitoring technology when the first yields no diagnosis.

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Abstract

Introduction: Diagnostic ambulatory ECG (AECG) monitoring is widely used for evaluating

syncope/collapse. In Europe, 2 sets of practice guidelines (National Institute for Health and

Clinical Excellence [NICE] and European Society of Cardiology [ESC]) provide

recommendations concerning selection of optimal AECG devices. However, whether

physicians in clinical practice select AECGs based on published guidelines is unclear. This

study examined the clinical practice of Emergency Department (ED) and Cardiologists in

two European countries: Germany (D) and United Kingdom (UK).

Methods and Results: A quantitative survey was undertaken. One-hundred-seventy-seven

respondents participated (ED: UK 33, Germany 40; Cardiology: UK 54, Germany 50). The

choice of AECG technology varied by specialty. Thus, among ED physicians, despite

patients having daily symptoms, 20% (UK), 31% (D) of respondents chose an AECG

technology other than Holter monitor. Conversely, when monitoring for infrequent events

(<monthly), 15-30% (UK & D) indicated choice of 24-48 hour Holter, 15-30% (UK & D) a

conventional event recorder and only ~50% select an insertable cardiac monitor (ICM) .

Among Cardiologists, 6% (UK) 10% (D) would not choose a Holter for daily symptoms

and, for infrequent symptoms, ~80% would select an ICM (UK & D). Many cardiologists

(UK & D) persist with Holters for infrequent events even after repeated failure of that

technology to provide a diagnosis.

Conclusions. In evaluation of syncope/collapse, most UK and German ED physicians and

Cardiologists use AECG’s according to practice guidelines, but a substantial minority

diverge from guideline recommendations in the choice of AECG technology.

Key Words: Ambulatory ECG monitoring, syncope, collapse, insertable cardiac monitor.

Abstract Word count: 246; Text, Figures, Tables & References: Word count: 3671

Condensed AbstractAre Syncope Guidelines are followed for selection of diagnostic ambulatory ECG

technology (AECG) in European Emergency and Cardiology Departments?

A United Kingdom and German survey allows these conclusions: in evaluating

syncope/collapse, most physicians use AECGs along practice guidelines, but

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a substantial minority diverges from recommendations.

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Introduction

Syncope and collapse (syncope/collapse) account for ~1% of European Emergency

Departments (ED) case load (1,2). While many episodes of syncope/collapse prove

benign, it is not always so; injury, accidents, reduced quality of life and, rarely, death, with

cardiac syncope raising greatest concern (3,4). Thus, understanding the basis of the

patient's symptoms, and developing effective prevention is important.

In the United Kingdom (UK) and Germany there are 2 sets of practice guidelines covering

diagnostic evaluation of syncope/collapse patients (4,5). Two references are given for the

European Society of Cardiology (ESC) 2009 version (4) that were in use during the

present study, recently updated 2018 (5) The National Institute for Health and Clinical

Excellence (NICE) guidelines are predominantly followed in the UK (6), while the ESC

guidelines are followed in Germany (4,5). Both guidelines offer diagnostic strategies for

determining syncope/collapse aetiology. Briefly, if a cause is not identified by initial

medical history, physical examination and 12-lead ECG (4), the next step is usually short-

or longer-term diagnostic ambulatory ECG (AECG) monitoring.

Appropriate choice among the diverse currently available AECG monitoring technologies

is important. Recommendations for selection of appropriate AECG technology are

provided in guidelines (4-6), recent publications (7-9), and the Syncope Unit Project

(10,11). Specifically, both NICE and ESC guidelines documents recommend use of Holter

monitors when event recurrence rates are very frequent (daily), wearable event monitors

are indicated for less frequent episodes (weekly-monthly), and insertable cardiac monitors

(ICMs) when symptoms occur infrequently (4-6).

The principal objective of the survey reported here was to ascertain the 'real world' manner

in which available diagnostic AECG monitoring technologies are selected by ED and

Cardiology clinicians practising in UK and Germany. The goal was to determine whether

clinical practice corresponds to current guidelines and where they diverge to develop

understanding of the reasons for such differences.

Methods

This report comprises findings obtained from a survey undertaken from July to December

2015 of ER and Cardiology physicians in UK and Germany. The survey was conducted by

an independent polling agency (ZS Associates, Evanston, IL, USA). Care was taken to

avoid identification of specific device manufacturers. The study was sponsored by

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Medtronic Inc. Minneapolis, MN, USA but sponsor personnel did not participate in

recording or interpreting the observations. An honorarium of ~US$100 was paid to

respondents after questionnaire completion.

Physicians, selected from hospital staff lists, who indicated interest in participating in the

survey underwent qualification prior to acceptance. Respondents were deemed qualified if

they fulfilled the following criteria:

a) Currently 2-30 years post-training

b) Board certified in their specialty

c) >75% of their time spent caring for patients

d)[c)] for ED physicians and non-implanting cardiologists: reported caring for >5

syncope/collapse patients/month of whom >50% were suspected to be of cardiac

origin . Respondents were asked to exclude accidental falls or epileptic seizures.

e) for Implanting Cardiologists: reported caring for >2 syncope/collapse cases/month

and implanting >5 ICMs in past year. Accidental falls and epileptic seizures were again

excluded.

f) were aware of the variety of wearable ambulatory diagnostic ECG technologies

available and had knowledge of ICMs.

Qualified respondents completed a quantitative survey instrument on-line; ED physicians:

33 UK and 40 German; implanting cardiologists (IC): 54 UK and 50 German; non-

implanting cardiologists (NIC): 14 UK and 20 German.

Data Analysis

The statistical plan required a sample size of ~30 qualified individuals for each physician

sub-group, which allowed sufficient qualified respondents assuming that test parameters in

the larger population of physicians in that sub-specialty are normally distributed.

Hypothesis testing was conducted using z-test and Student’s t-test for proportions and

averages respectively to ensure that samples compared belonged to equivalent

populations. Statistical significance was set at 95% confidence level.

Results

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Findings summarised here comprise questionnaire responses from 177 physicians (73 ED

and 104 cardiology) who met qualification criteria and completed questionnaires. The

years of practice experience were, for UK responders, m14.4 for ED physicians, 12.9 for

NICs and 24.5 for ICs.

All UK ED physicians and 85% of German ED physicians worked in public hospitals. For

NICs, UK and Germany public hospital percentages were 93% and 58% respectively,

whereas for ICs the public hospital percentages were 98% and 82% respectively.

NICs and ICs were questioned regarding the syncope/collapse diagnoses, that they

encountered, as a percentage of all patients There were no significant differences

between UK and German cardiologists and the data are combined (Table 1, percentage

data are provided as mean ± SD, 25th -75th quartile).

Factors Driving Monitor Technology Choice

The primary factors driving selection of a particular monitoring technology for a given

TLOC (transient loss of consciousness) patient was evaluated (Figure 1, Table 2). Both

ED physicians and Cardiologists in UK and Germany indicated that the most important

driver was their impression of obtaining a useful diagnostic yield. Second in importance

was frequency with which TLOC recurrence was expected (Figures 2 and 3).

In terms of device choice, both UK and German physicians tended to follow guidelines

appropriate to their regions (NICE in UK [6] and ESC in Germany [4]), but in each case

there were important divergences, these were particularly notable among ED physicians

who may be expected to be less familiar with guidelines than are cardiologists.

1. ED Physicians (Figures 2 and 3) The survey findings revealed that most UK ED physicians (80%) follow NICE guidelines

(6) for Holter for daily symptoms, but diverged from NICE for Holter recordings if expected

frequency of events was 2-3/week, when 73% preferred event monitors or ICMs to Holters

(p<0.05). However, ~30% of these same physicians indicated, in contradistinction to NICE

recommendation for ICM, that they would select wearable event monitors or Holter even

for anticipated episode recurrences of <6 monthly (Figure 2).

Among German ED physicians, 69% follow ESC guidelines for Holter with daily symptoms

(p <0.05 vs Event/ICM); the remainder prefer longer-term monitors (Figure 3). However,

only 46-54% would follow ESC guidelines for ICM use when event frequency is <6

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monthly. About one-third of UK ED physicians would continue with Holters or wearable

event recorders, compared with German physicians ranging from 15-25% (Figure 3).

2. Cardiologists (Figures 4 and 5)UK cardiologists (94%) follow NICE guidelines Holter recommendations for daily

symptoms, but only 43% follow NICE recommendations for Holter recordings for event

frequencies of 2-3/week. Most UK cardiologists (75-83%) follow NICE guidelines for ICM

use when symptoms are expected <6 monthly (Figure 4).

German cardiologists also largely follow ESC guidelines for Holter recorders for daily

symptoms (90%) (Figure 5). In addition, 70% follow recommendations for Holter

recorders when expecting event rates of 2-3/week. Further, German cardiologists closely

follow ESC guidelines for use of ambulatory monitors in patients with low frequency

symptoms, with 76-82% recommending ICMs.

Repeat monitoring

Often, the initial monitoring may not provide a definitive diagnosis, in such cases,

physicians may decide to continue ambulatory ECG monitoring for an additional period of

time ('follow-up monitoring'). The survey examined physician preferences regarding their

follow-up monitoring strategy. In this assessment, responses were divided into ED

physicians, cardiologists practising primarily in hospitals, and cardiologists primarily office-

based (Figure 6).

Findings reveal that many physicians persist with the same methodology. In general,

although differences were not statistically significant, the survey suggested that German

physicians, both ED and cardiologists tended to repeat the same monitoring more so than

did UK physicians (Figure 6). The main factors driving repeated use of the same external

monitoring tool is summarized in Table 2. Here, the most important drivers were ease of

use of external monitoring (UK 73%, Germany 60%), and non-invasive nature of the

monitor (UK 64%. Germany 60%) (Table 2).

Discussion

Main Findings

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This survey examined the current 'real world' application of both wearable ambulatory

ECG recorders and insertable cardiac monitors for diagnosis of patients presenting with

'syncope/collapse' by UK and German EDs and cardiologists. As there are 2 pertinent

guidelines available (NICE in UK [6], ESC Syncope guidelines in Germany [4]) we aimed

to ascertain the degree to which clinical practice conformed to appropriate regional

guidelines. There were 4 main findings. First, both sets of guidelines emphasize that

choice of monitor type should be based on expected time to syncope recurrence. Thus,

the survey indicated that AECG monitoring strategies of most EDs and cardiologists

largely conform to guidelines but, important divergences were identified. The vast majority

of physicians appropriately use Holter monitors as recommended for daily symptom

recurrences. However, the majority depart from the same Holter recorder

recommendations, preferring longer-term event recorders, when expected event

recurrence is 2-3/week. Conversely, while most physicians adhere to guidelines to use

ICM's for very infrequent events (<6monthly), a substantial minority (~30%) indicated

preference for short-/intermediate-term monitoring over ICMs.

Second, UK and German cardiologists appeared to follow their regional practice

guidelines more closely than did ED physicians. Perhaps, due to the fact that ED

practitioners face such a broad range of problems, they are less likely to be as familiar

with primarily cardiology-based AECG guidelines.

Third, when repeat AECG monitoring was needed in patients in whom initial AECG

recordings were unrevealing, a substantial proportion of physicians indicated that they

tend to persist with the same technology, even though it has previously proved non-

diagnostic.

Finally, the relative frequency of syncope/collapse diagnoses, as reported by the

cardiologists surveyed, was similar in both UK and Germany . Consequently, any variance

regarding AECG monitoring strategies among cardiologists cannot be attributed to patient

population differences.

Choosing Among AECG Monitor Technologies

AECG monitors, both wearable and insertable, are now widely used by physicians

throughout the world for evaluation of cause of many troublesome symptoms likely due to

cardiac arrhythmia, including palpitations, lightheadedness, collapse, and transient or fixed

neurological disturbances (transient ischaemic attacks [TIAs], cryptogenic stroke). The

recently updated ESC Syncope guidelines (4,5), and NICE guidelines on syncope/collapse

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(6) are concordant in terms of recommending that monitoring should be selected based on

the clinician's estimate of predicted time to symptom recurrence.

In the survey performed here, we found that UK and German physicians largely

followed available practice guidelines but in a substantial minority there were

discrepancies. Similar observations were obtained in our recent physician survey in US

(8), where we probed 'real world' AECG practice patterns in a broad group of physicians:

ER physicians, Hospital-based internal medicine physicians, cardiologists and

neurologists. The key findings again revealed that, while the majority of practitioners

conformed to available guideline recommendations, there were important departures. A

substantial minority the magnitude of which was lowest among cardiologists (10%) and

highest among primary care physicians (40%) chose intermediate or long-term AECG

recording devices for documenting ‘daily’ events. An even larger minority, lowest among

cardiologists (15%) and among EDs (72%) chose short-/intermediate-term monitoring

despite anticipating very low recurrence rate (1/year).

Based on observed device selection by EDs and cardiologists in this report, it is apparent

that factors other than technology alone impact device choice. For example, expectation

regarding patient compliance may influence physician technology preference, including

patient intolerance of cutaneous ECG electrodes, cumbersome nature of devices, or

desire to assess treatment effect after diagnosis may prompt physicians toward ICMs at

an early stage of evaluation. Current generation insertable cardiac monitors offer recording

of up to 3 years, very low risk of skin irritation or infection and almost imperceptible

surgical scars.

Limitations

The interpretation of findings in this survey is subject to several limitations. First, although

meeting the pre-determined statistical plan, the number of respondents was small,

Second, responses from survey participants were based on recollection of recent practice

which inevitably reduces overall quality of data compared with prospective studies. Third,

in most European hospitals it is not customary for ED physicians to initiate AECG

monitoring. However, while UK and German ED physicians may be prescribing monitoring

more often than expected, it is likely that follow-up is by cardiologists, and consequently

EDs impression of utility of various technologies may be incomplete. We did not address

this aspect of AECG care. Fourth, it is possible that not all AECG technologies were

readily available in all geographies, and insurance coverage may have limited choice in

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some circumstances. Moreover, use of guidelines by physicians is not always as up-to-

date as may be ideal. In this matter, ESC Guidelines of 2009 (4) brought the ICM more

into the foreground of investigation compared with those of 2004 (12), thus, following the

2004 guidelines might have been undeclared and influenced results. Finally, clinician

responses may have been influenced by having been offered an honorarium, despite the

honorarium source was concealed.

Conclusion

In conclusion, in the evaluation of syncope/collapse, most UK and German Emergency-

Department and Cardiology clinicians appear to employ Ambulatory-ECG technology

appropriately based on regional guidelines (NICE in UK, ESC in Germany). Nonetheless,

in a substantial minority there remain divergences between choice of monitoring

technology and guideline-based recommendations.

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References 1. Blanc JJ, L’Her C, Touiza A, Garo B, L’Her E, Mansourati J. Prospective evaluation

and outcome of patients admitted for syncope over a 1 year period. Eur Heart J

2002;23:815–820.

2. Disertori M, Brignole M, Menozzi C, Raviele A, Rizzon P, Santini M, et al.

Management of patients with syncope referred urgently to general hospitals. Europace

2003; 5: 283–291.

3. D'Ascenzo F, Biondi-Zoccai G, Reed MJ, Gabayan GZ, et al. Incidence, etiology and

predictors of adverse outcomes in 43,315 patients presenting to the

Emergency Department with syncope: an international meta-analysis. Int J Cardiol

2013;167:57-62.

4. Moya A, Sutton R, Ammirati F, Blanc JJ, Brignole M, Dahm JB, et al.

The task force for the diagnosis and management of syncope of the European Society of

Cardiology (ESC). Guidelines for the diagnosis and management of syncope (version 2009).

Eur Heart J 2009; 30: 2631-2671.

5. Brignole M, Moya, A, de Lange FJ, Deharo J-C, Elliott PM, Fanciulli A, et al.

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2018 ESC Guidelines for diagnosis and management of syncope. The Task

Force for the Diagnosis and Management of Syncope of the European Society of

Cardiology (ESC). Eur Heart J 2018; -39: 1-69. Doi:10.1093/eurheartj/ehy037

6. National Institute for Health and Clinical Excellence. Transient loss of consciousness

(‘blackouts’) management in adults and young people. London: NICE; 2010. NICE

clinical guideline 109. http://guidance.nice.org.uk/CG109/NICEGuidance/pdf/English

7. Kohno R, Nantsupawat T, Benditt DG. Trends in Subcutaneous Cardiac Monitoring

Technology. J Innovations Cardiac Rhythm Management (In Press 2018).

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Diagnostic ECG Monitoring for Syncope and Collapse: An Assessment of Current

Clinical Practice in the United States. Pacing Clin Electrophysiol 2018;41(2):203-20

9. Brignole M, Alboni P, Benditt D, Bergfeldt L, Blanc JJ, Bloch Thomsen PE, et al.

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evaluation of patients with syncope. Europace 2001 3(4): 253-260.

10.Brignole M, Ammirati F, Arabia F, Quartieri F, Tomaino M, Ungar A, et al.

Assessment of a standardized algorithm for cardiac pacing in older patients affected by

severe unpredictable reflex syncopes. Eur Heart J 2015; 36: 1529-1535.

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11.Brignole M, Arabia F, Ammirati F, Tomaino M, Quartieri F, Rafanelli M, et al,

on behalf of the Syncope Unit Project 2 (SUP 2) investigators. Standardized algorithm for

cardiac pacing in older patients affected by severe unpredictable reflex syncope: 3-year

insights from the Syncope Unit Project 2 (SUP 2) study. Europace 2016;18: 1427-1433.

12.Brignole M, Alboni P, Benditt D, Bergfeldt L, Blanc JJ, Bloch Thomsen PE, et al.

Task force on syncope, European Society of Cardiology. Guidelines on Management

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2004; 6: 467-537.

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Figures and Legends

Figure 1: Clinical Factors Driving Choice of Ambulatory ECG Monitor Technology by UK and

German Physicians.

ED= Emergency Department

Card= Cardiology

TLoC= transient loss of consciousness

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Figure 2:Comparison of UK ED Physician Choice of Monitoring Technology vs NICE

Recommendations Based on Anticipated TLOC Recurrence Frequency. See text for

explanation.

NICE= National Institute for Health and Clinical Excellence, TLOC=transient loss of consciousness, HCP= health care provider, ICM/ILR=Insertable cardiac monitorED=Emergency Department

17

Figure 3Comparison of German ED Physician Choice of Monitoring Technology vs ESC Guideline

Recommendations Based on Anticipated TLOC Recurrence Frequency. See text for

explanation

TLOC=transient loss of consciousness, HCP= health care provider, ICM/ILR=Insertable cardiac monitorED=Emergency Department

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Figure 4Comparison of UK Cardiology Physician Choice of Monitoring Technology vs NICE

Recommendations Based on Anticipated TLOC Recurrence Frequency. See text for

explanation

NICE= National Institute for Health and Clinical Excellence, TLOC=transient loss of consciousness, HCP= health care provider, ICM/ILR=Insertable cardiac monitor

Figure 5

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Comparison of German Cardiology Physician Choice of Monitoring Technology vs ESC

Guideline Recommendations Based on Anticipated TLOC Recurrence Frequency. See

text for explanation

TLOC=transient loss of consciousness, HCP=health care provider, ICM/ILR=Insertable cardiac monitor

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Figure 6

Percent of UK and German Physicians Who Reported Repeating the Same Type of Monitor System Multiple Times in the Same Patients

ED=Emergency Department physicians, CARD (IN)=hospital cardiologists, CARD (OUT)=office-based cardiologists.

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TablesTable 1

Estimated Frequency of Diagnoses Among Newly Presenting Syncope/Collapse Patients in UK and Germany

as a Percent (%) of All Diagnoses

RespondentType

Mean Value

Standard Deviation (SD)

25th Percentile

75th Percentile

Cardiac Causes

NIC 17% 7% 10% 22%

IC 20% 12% 12% 25%

Neurological

Conditions*NIC 8% 18% 6% 9%

IC 6% 18% 3% 8%

Reflex Syncope

NIC 20% 55% 10% 24%

IC 18% 57% 8% 27%

Orthostatic Hypotensio

nNIC 11% 29% 7% 11%IC 10% 38% 5% 12%

° %. ‘Neurological conditions’ consisted of psychogenic pseudosyncope/pseudoseizures or collapse associated with acute cerebrovascular conditions.NIC= Non-implanting cardiologistsIC= Implanting cardiologists

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Table 2Reasons Provided for Repeating Same External Monitor Technology Multiple Times

in Same Patient

UK ER

UK Hosp Cardiol

UK Outside Cardiol

Germany ER

Germany Hosp Cardiol

Germany Outside Cardiol

Ease of external monitor use

73% * 40% 30% 60% 48% 43%

Noninvasive nature

64%* 35% 52% 60% 45% 37%

Low cost 27% 30% 30% 33% 42% 33%

Burden of Follow-up with Ext Monitor

9% 0% 9% 13% 30% 32%

Burden of Follow-up with ICM

27% 0% 9% 20% 27% 40%

Patient request

18% 15% 19% 20% 21% 27%

ICM= insertable cardiac monitor Ext Monitor= External monitors, some with telemetry

* p<0.05 vs UK cardiologists

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