Adaptation of a holistic framework to the analysis of the remote monitoring service of cardiac implanted devices at Niguarda Hospital

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POLITECNICO DI MILANO

Scuola di Ingegneria Industriale e dell’Informazione

Corso di Laurea Magistrale in Ingegneria Biomedica

Adaptation of a holistic framework to the

analysis of the remote monitoring service of

cardiac implanted devices at Niguarda Hospital

Relatore: Prof. Enrico G. Caiani

Correlatore: Dr.ssa Emanuela T. Locati

Tesi di laurea di:

Greta M. Merlotti Matr. 836467

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I

Index

Figures Index ... IV

Tables Index ... VII

Acknowledgments ... X

Ringraziamenti ... XI

Summary ... XII

Sommario ... XXI

Chapter 1 - Introduction ... 1

1.1 Implantable devices ... 1

1.1.1 Implantable loop recorder ... 1

1.1.2 Pacemaker (PM) ... 3

1.1.3 Implantable cardioverter device (ICD) ... 6

1.1.4 Cardiac resynchronization therapy (CRT) ... 9

1.2 European spreading of devices ... 11

1.3 Control of implantable devices ... 16

1.4 Example of benefits of remote disease monitoring ... 19

1.4.1 Atrial fibrillation (AF) ... 19

1.4.2 Heart failure (HF) ... 22

1.5 Remote Monitoring Development... 24

1.6 Devices classification and economic aspects ... 26

1.7 Remote Monitoring organizational model and benefits ... 35

Chapter 2 - Methods ... 41

2.1 Varied analytical approaches ... 41

2.2 Holistic framework ... 43

2.2.1 Description of the Holistic model ... 44

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II

Chapter 3 - Contextual Inquiry Analysis ... 47

3.1 Service structure ... 47

3.1.1 Data from field observation and databases ... 47

3.1.2 Service regulation ... 50

3.2 Contextual Inquiry results ... 51

3.2.1 Niguarda experience ... 51 3.2.2 Medtronic devices ... 53 3.2.3 Privacy ... 55 3.2.4 Niguarda workflow ... 57 3.2.5 Timing ... 59 3.2.6 Outpatient visits ... 61

3.2.7 Remote monitoring reimbursement ... 63

3.3 Value specification ... 63

Chapter 4- Design... 66

4.1 Model review ... 66

4.1.1 Patient empowerment ... 66

4.1.2 Circular Model ... 67

4.1.3 Digital Health literacy ... 68

4.1.4 Patient adherence to RM service ... 69

4.2 Database modification proposal ... 71

4.2.1 Color Code creation ... 71

4.2.2 Phone call classification ... 74

4.3 Improvement of the human resources workflow ... 78

4.3.1 Literature revision ... 78

4.3.2 Timing calculation ... 82

4.3.3 Comparison ... 84

4.4 Reimbursement ... 87

4.4.1 Economic Literature review ... 87

4.4.2 Italian reimbursement model of the remote monitoring service ... 92

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III

Chapter 5 – Operationalization ... 97

5.1 Adherence results ... 97

5.2 Color Code results ... 99

5.3 Phone call statistics ... 102

5.3.1 Analysis of year 2013 ... 102

5.3.5 Comparison of phone calls from 2013 to 2016 ... 110

5.3.6 Analysis of year 2016 (June-December) ... 111

5.4 Reimbursement application ... 112

Chapter 6 - Summative evaluation ... 114

6.1 Adherence ... 114

6.2 Database implementation ... 114

6.2.1 Service Database ... 114

6.2.2 Color Code ... 115

6.3 Timings ... 115

6.3.1 Phone calls database ... 116

6.4 Reimbursement ... 116

References ... 118

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IV

Figures Index

Figure 1 Medtronic REVEAL LINQ [w2] ... 2

Figure 2 Hyman design of the first “artificial pacemaker” [5] ... 3

Figure 3 Representation of Abrams PM [w3] ... 4

Figure 4 PM Medtronic Advisa MRI SureScan PM [w2] ... 5

Figure 5 Medtronic Evera DR ICD [w2] ... 7

Figure 6 Lead II ECG showing Torsades being shocked by an ICD back to the patient's baseline cardiac rhythm [w5]... 9

Figure 7 CRT-D implant [w2] ... 9

Figure 8 Medtronic Amplia, Compia CRT-D Secure-Scan [w2] ... 10

Figure 9 PM spreading- units per million inhabitants, Courtesy of Medtronic ... 12

Figure 10 Defibrillators spreading- units per million inhabitants, Courtesy of Medtronic ... 13

Figure 11 CRT-P spreading- units per million inhabitants, Courtesy of Medtronic . 14 Figure 12 CRT-D spreading- units per million inhabitants, Courtesy of Medtronic . 15 Figure 13 Traditional follow-up (blue arrow) vs remote follow-up (yellow arrow) [16] ... 18

Figure 14 FA ECG vs Normal ECG [17] ... 19

Figure 15 FA incidence over Italian population [18] ... 20

Figure 16 AF percentage [19] ... 20

Figure 17 Heart Failure ECG [20] ... 22

Figure 18 HF prevalence based on age [24] ... 23

Figure 19 European RM refund situation [w8] ... 34

Figure 20 RM AIAC organization model [19] ... 35

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V Figure 22 Mean time to diagnosis of clinical events in remote vs clinic follow-up

[29] ... 39

Figure 23 Median time from event to clinical decision: remote vs. clinical follow-up [29] ... 39

Figure 24 Holistic Framework: CeHRes roadmap [51] ... 45

Figure 25 Alert conditions for Reveal LINQ Wireless Devices [w2] ... 48

Figure 26 Patients database chronological displacement errors; in column ARRUOL (first enrollment), patients were not recorded in chronological order ... 49

Figure 27 Phone calls database ... 49

Figure 28 Medtronic CareLink website [w9] ... 50

Figure 29 Patient and followed with RM Medtronic CareLink at Niguarda Hospital52 Figure 30 Medtronic CareLink system [w2] ... 53

Figure 31 Medtronic type of transmissions [w2] ... 55

Figure 32 Activities list as a result of implanting: enrollment and first transmission 58 Figure 33 Activities list as a result of the received transmission... 59

Figure 34 Circular RM Model ... 67

Figure 35 Example of "Color Code" design ... 74

Figure 36 RM timing literature comparison [32-57-58-59-60-61-62] ... 80

Figure 37 Timing comparison ... 85

Figure 38 Real and aim timing comparison ... 86

Figure 39 Patient and Hospital timing comparison ... 87

Figure 40 On time/ late transmission distribution ... 97

Figure 41 Percentage of on time and late transmissions ... 98

Figure 42 Unscheduled transmissions distribution ... 99

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VI

Figure 44 Planned transmissions (PT) distribution... 100

Figure 45 PT percentage ... 101

Figure 46 2013 phone calls distribution ... 103

Figure 47 2013 Phone calls categories percentage ... 104

Figure 54 2013-2016 mean comparison (overall mean =134) ... 110

Figure 56 2013-2016 and 2016b comparison ... 112

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VII

Tables Index

Table 1 Class of recommendation [25] ... 27

Table 2 Level of evidences [25] ... 28

Table 3 RM recommendations [25] ... 28

Table 4 Recommendations of the Consensus Document HRS 2015 on RM [26] ... 30

Table 5 European refound. [w8] ... 33

Table 6 Timing before the advent of RM (min*year*patient) ... 60

Table 7 Timing during early years of telemonitoring ... 60

Table 8 Timing of actions required by the patients, before and after the advent of RM service ... 61

Table 9 Total number of outpatient visits per year ... 62

Table 10 Total outpatient visits row marginal mean and mode ... 62

Table 11 Outpatient visits mean and mode per patient ... 63

Table 12 Number of phone calls ... 75

Table 13 Phone calls reasons ... 76

Table 14 Phone calls sub-categories ... 77

Table 15 Phone call duration ... 78

Table 16 Timing comparison based on literature research [32-57-58-59-60-61-62] 79 Table 17 Calò-Niguarda RM timing comparison [61] ... 81

Table 18 Calò-Niguarda control group comparison [61] ... 81

Table 19 Training time per year (min) ... 82

Table 20 Number of transmissions after censoring per year ... 83

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VIII Table 22 Transmissions revision timing per year (min), consisting in

transmission*patient*year * revision timing (15 min for technician, 5 min for

physician) ... 83

Table 23 Phone calls timing per year ... 84

Table 24 On-field mesured timing ... 85

Table 25 Activities timing aim ... 86

Table 26 Patient timing ... 86

Table 27 Raatikainen results [62] ... 89

Table 28 Cost incurred by hospital administration per patient [61] ... 89

Table 29 Social costs per patient in a year [61] ... 90

Table 30 Overall mean annual costs per patient in SC group and RM group [63] .... 91

Table 31 Diffusion of implantable devices in Lombardy ... 94

Table 32 On time and late transmissions per year ... 97

Table 33 On time and late transmissions ... 98

Table 34 Adherence percentage ... 98

Table 35 Color code statistics ... 102

Table 36 Phone calls reason per months, year 2013 ... 103

Table 37Average number of phone calls on 11 months, Max and Min number of monthly phone calls in year 2013 ... 103

Table 39Average number of phone calls on 11 months, Max and Min number of monthly phone calls in year 2014 ... 105

Table 41 Average number of phone calls on 11 months, Max and Min number of monthly phone calls in year 2015 ... 107

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IX Table 43 Average number of phone calls on 11 months, Max and Min number of monthly phone calls in year 2016 ... 109

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X

Acknowledgments

This thesis is the realization of a collaborative project between the Politecnico di Milano and Niguarda Ca’ Granda Hospital, conceived and developed during the academic year 2015-2016.

Particularly, this has been possible thanks to the availability and enthusiasm of Dr. Emanuela T. Locati, cardiologist in the Cardiology 3-Electrophysiology Department at Niguarda Ca’ Granda Hospital and the head cardiologist Dr. Maurizio Lunati. Additional important contributions were made by Dr. Giulia Imo and Franca Negrini, electrophysiology technician and nurse in charge of the remote monitoring service, respectively and Medtronic Ing. Sabrina De Cicco.

Moreover, nothing could have been achieved without the precious support of Prof. Enrico G. Caiani, PhD, Associate Professor in Biomedical Engineering and e-Health at Politecnico di Milano, who made possible the cooperation with Dr. Locati and the realization of this experience.

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XI

Ringraziamenti

Questa tesi è la realizzazione di un progetto di collaborazione tra il Politecnico di Milano e l’Ospedale Niguarda Ca’ Granda, ideato e sviluppato durante l’anno accademico 2015-2016.

In particolare, questa esperienza è stata resa possibile grazie all’entusiasmo e alla disponibilità della Dott.ssa Emanuela T. Locati, medico cardiologo nel reparto di Cardiologia 3- Elettrofisiologia dell’Ospedale Niguarda e al direttore del dipartimento Dott. Maurizio Lunati.

Fondamentali contributi nello svolgimento del lavoro sono stati apportati dalla Dott.ssa Giulia Imo e Franca Negrini, tecnico di elettrofisiologia e infermiera incaricati del servizio di controllo remoto, e dall’ Ing. Sabrina De Cicco di Medtronic.

Infine, nulla sarebbe stato ottenuto senza il prezioso supporto del Prof. Enrico G. Caiani, PhD, Professore Associato in Ingegneria Biomedica e e-Health presso il Politecnico di Milano, il quale ha reso possibile la collaborazione con la Dott.ssa Locati e la realizzazione di questa esperienza.

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XII

Summary

Nowadays Remote Monitoring (RM) service is a reality established in the Italian hospitals and for this reason it requires a specific description of assets, clear guidelines and a verification of the service. The available resources and the problems encountered by operators and patients analysing the situation, can lead to an improvement of the service from the practical, clinical and administrative point of view.

The aim of the project was to analyze the actual situation of RM service activities in the case of chronic disease management. Involving all the possible stakeholders and studying how the RM service is actually performed in the Niguarda Hospital reality, can provide an overview of the service, its weaknesses and strengths, whose analysis allows the development of new ideas and proposals for a steady and gradual improvement of the patients’ satisfaction and adequacy of the operators.

All the considerations and analyses were based on stakeholders’ feedbacks and needs.

Introduction

The availability of Cardiac Implantable Electronic Devices (CIED) in clinical practice represents a crucial step in modern cardiology. Thanks to scientifically recognized efficiency in patient care, the adoption of these systems is increasing all around the world. CIED include: implantable loop recorder (ILR), pacemaker (PM), implantable cardioverter-defibrillator (ICD), cardiac resynchronization therapy (CRT or CRT-P), cardiac resynchronization therapy and defibrillator (CRT-D or CRT ICD or CRT+ICD). Telemedicine technologies and remote data transmission allow the control of technical and clinical parameters of a CIED, even when the patient is not at the hospital.

The Consensus Conference of AIAC (Associazione Italiana di Aritmologia e Cardiostimolazione) indicated that RM can supplement and replace the traditional ambulatory visit without compromising patient safety.

RM brings benefits related to the cure of some pathologies (e.g. atrial fibrillation and heart failure) and the opportunity of frequently monitoring patients’ heart rhythm and take timely action during any of pharmacological therapy.

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XIII RM helps to maximize the appropriateness consumption of healthcare resources, reserving treatments and diagnostic tests for those that actually need them.

Intelligent automated telemonitoring systems that communicate daily bi-directionally from the CIED to the RM service are available on the market: Home Monitoring by Biotronik, CareLink Network by Medtronic, Latitude by Boston Scientific, Merlin by St. Jude Medical and Smartview by Sorin.

The ESC (European Society of Cardiology) 2013 guidelines attribute to the RM, used for the early recognition of clinical and technical problems, the Class II recommendation and level of evidence A, but numerous evidences produced by the different studies defined recommendation Class I level of evidence A for CIED follow-up. Despite the previous definition, there is still lack of classification at economic level.

The AIAC has developed through its Telecardiolology Area a linear organizational model that has been recommended into the guidelines where the flow of information starts from the patients’ CIED and finishes with the RM operators.

Regarding the implementation of the model, the nurse / electrophysiology technician role consist in training and education of the patient, review of data and alarms, screening of transmissions and submission of clinical cases to the physician, contact with the patient (phone calls) and counselling. The physician tasks are: collection of informed consent, supervision and control of transmissions, programming devices, keep relationships with other specialists.

Important clinical trials have demonstrated the superiority of RM than the traditional control, in terms of: reduction of scheduled / unscheduled visits and their duration, reduction in ER accesses and hospitalizations, early identification of technical problems and clinically relevant events.

As regards the patients' satisfaction, RM avoids indirect health costs borne by the patient; more than 90% of patients finds RM easy or very easy to use and recommended, 78% of patients prefer RM to hospital visit, 83% of patients said they would be more comfortable thanks to RM.

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XIV

Methods

In order to examine the proper strategy to conduct the analysis of the RM service at Niguarda Hospital, a literature search of papers describing the design methods for eHealth technologies was performed; the following approaches were identified: user-centered design approach, multidisciplinary approach, stakeholders’ participation approach, iterative evaluation stages approach and performance approach.

These approaches define the stakeholder’ identification and continuous involvement in the design (importance of patient’s needs), the qualitative and quantitative data collection, continuous check and review of the innovations and the evaluation of the performance through all the defined aspects. To highlight the importance of each stage, a holistic approach that combines all the key points for health technologies description has been proposed by Van Gemert-Pijnen et al.

The model is based on a multidisciplinary mixed-methods approach to increase the cooperation between those who are responsible for producing the technology or create and deliver eHealth service and those who participate and use it to ensure that eHealth technologies fit in with the needs and values. It is divided in these sections: contextual inquiry, value specification, design, operationalization, summative evaluation.

The holistic approach tends to emphasize the importance of the whole and the interdependence of its parts, while avoiding separate analysis; for this reason, we decided to adapt the proposed holistic framework to conduct our analysis.

Contextual Inquiry and Value Specification

The analysis first focused on the service organization: the initial team was formed by a cardiologist, a nurse and a electrophysiology technician. The service was carried out in the department of Cardiology 3- Electrophysiology at Niguarda Ca' Granda Hospital. All the patients enrolled in the service are carriers of implantable Medtronic devices (PM, ILR, ICD-MONO, ICD-BIC, CRT) and use Medtronic CareLink monitor. The field observation has led to direct data collection (measurements) and indirect data collection, consisting in interviews to the operators and by consulting the databases. The participation to the project is voluntary and the service was initially provided for free, with no refund from the SSN to the structure.

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XV In December 2016, a total of 512 patients were enrolled, of which 343 regularly followed by the basic equipe (1 Physician, 1 Technician), according to the following classification: 127 CRT, 115 ICD-MONO, 34 ICD-BIC, 17 PM, 50 ILR.

According to the work-flow directly observed and compared with the Italian guidelines, the activities are described, with specific focus to the user: after the implant, the patient sign the informed consent submitted by the physician and the technician enrols, trains and delivers the technology to the patient; the RM service starts when the patient sends the first data transmission to the center. In the target date, the technician checks that all transmission are arrived and, after a first revision, submits clinical cases to the physician that creates the medical report; in case of need the patient is summoned for an outpatient visit.

The estimated time (min*year*patient) needed before the advent and during the early years of RM at Niguarda Hospital, based on operators’ personal experience, is the following:

 TECHNICIAN: training (0 min; 20 min), paperwork (0 min; 5 min), transmissions (0 min; 90 min), phone calls (5 min; 30 min), clinical management issues (20 min; 0 min), total (25 min; 145 min);

 PHYSICIAN: training (0 min; 5 min), paperwork (15 min; 5 min), transmissions (0 min; 20 min), phone calls (15 min; 5 min), clinical management issues (60 min; 30 min), total (90 min; 65 min);

 HOSPITAL: paperwork (30 min; 10 min), total (30 min; 10 min).

The timings needed by the patient for the different actions before and after the advent of RM are: training (0 min; 20min), paperwork (30 min; 10 min), transmissions (0 min; 10 min), phonecalls (20 min; 35 min), clinical management issues (60 min; 25 min), moving (150 min; 60 min), total (260 min; 160 min).

A group of 53 ICD carriers patients made a mean of 2 outpatient visits/year for years 2011, 2012, 2015, 1 visit/year for years 2009, 2010,2013,2014,2016, the mode is 2 visits/year only for year 2011, 1 visit/year for the others. In 2011 (year of RM enrollment) the patients made twice the number of outpatient visits due to the beginning of the study at Niguarda Hospital.

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XVI The information flow, along with the demonstrated importance of user-centered eHealth design, gives rise to a model with a circular structure in which the flow is never interrupted; the model, already used at Niguarda Hospital, needs a precise definition.

The main problem found in the RM service was the optimization of the resources: timing and lack of structured databases (missing data, misclassification of data, insufficent description of data, uncertainty of data). The possible implementation is the creation of an encoding system that increments operators’interoperability and databases structuring. The absence of an effective reimboursement at Niguarda Hospital leads to an economic disadvantage in the face of a proven clinical benefit.

Design

The first proposed improvement regards the organizational working model used in RM: as observed at Niguarda, the model has a circular workflow of information, in which the patient's centrality in chronic diseases care is highlighted. The information flow starts from the patient’s CIED and, after the RM activity, finishes to the patient itself.

To understand the acceptance, involvement and usage skills (Digital Health Literacy) that patients have in the context of the RM technology, the data from a selected group of patients, carriers of ILR device were analyzed. Starting from the definition proposed by WHO, the definition of adherence was contextualized in the RM service to ILR device use: percentage of the ratio between the number of on-time transmissions and the total of the expected transmissions for each individual patient.

A possible aim was to improve the databases, according to operators’ needs and based on every-day practice, for example the creation of a “Color Code” to be assigned to the patient, explanatory of his/her condition and the needed degree of care (based on medical report of transmissions: red for hospitalization, orange for outpatient visit, yellow for less than 3 months transmissions interval, green for 3 months transmissions interval, blue for technical problems, violet for device replacement).

Our goal was to assign a score to the patient that result immediately understandable by the operator and it gives the overall patient situation, to provide an initial and simplified idea of his/her conditions, before the operator could access the complete medical records.

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XVII An additional improvement is related to the phone calls databases, in order to create a better definition of the calls reasons in a structured database; starting from the annotated main reasons of call, recurring patterns of reasons and theirs duration have been identified as follows:

 transmissions and battery (2 min);

 symptoms, visit planning, acoustic alarm, Optivol (4 min);  other and technical problems (6 min)

Starting since June 2016, the operators at Niguarda Hospital have been using the proposed categorization in the database.

The main resource in the RM service is the operators’ working time; a quantitative analysis about the timing actually used for the activities was performed. This verification, compared to the information reported in the literature, can demonstrate the time needed to the practice of the service, and define if there are possible improvements in the usage of these resources. Based on data collected from March 2016 to December 2016 ( min *patient*year):

 TECHNICIAN: training 5 min (20 min to add for the first enrollment), paperwork 5 min, transmissions 140,8 min, phone calls 18,5 min, total 169,3 min;

 PHYSICIAN: paperwork 5 min, transmissions 46,9 min, phone calls 5 min, clinical management issues 30 min, total 86,9 min;

 HOSPITAL: paperwork 10 min, total 10 min.

It can be noted that, although the total time spent by the hospital (sum of technician, physician and hospital time) before and after the advent of the RM is increased ( 145 min ; 247,7 min), the patient has a considerable gain of time (260 min; 134min).

The following price has been identified in the Tariffario Medicina Specialistica Ambulatoriale and was considered appropriate for the basic pricing of the remote telemetry control of the bearers of CIED patients for a calendar year: 89.54 Monitoring telemetry electrocardiographic  estimated 46.50 EUR.

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XVIII  89.54 ECG telemetry ILR and PM  estimated 46.50 EUR

 89.54.6 ECG telemetry, RM for ICD  estimated 56.50 EUR  89.54.7 ECG telemetry, RM for CRT  estimated 66.50 EUR

Operationalization

The Operationalization chapter describe the implementation of proposals designed in the previous chapter.

On the total of transmissions expected in a four years period of 18 ILR bearers, the percentage of late transmissions was equal to 14%, resulting in 86% of adherence.

For 53 patients analyzed in 6 years, the Color code result in:

 UNSCHEDULED TRASMISSION: 25% green, 51% yellow, 3% orange, 0% red, 20% blue, 1% violet.

 PLANNED TRASMISSION: 41% green, 55% yellow, 1% orange, 0% red, 1% blue, 2% violet.

The mean score obtained retrospectively examining all the transmissions used to implement the code is 0,6.

To validate the phone calls classification, a separate analysis of the second half of 2016 (b), in which the operator used the new classification, was conducted.

The comparison between the mean of years from 2013 to 2016 and the second half of 2016 shows that the “other” category decreased; this could be related to the fact that the phone calls were redistributed in a more precise manner in the defined categories (e.g. transmission, symptoms and visit planning).

The CAR-LIN ambulatory started in November 2016 with pricing method proposed. At present, with the basic equipe, Niguarda Hospital is undertaking a pricing pilot project, following a maximum of 500 patients over a calendar year.

At the end of December 2016, with 343 active patients enrolled, the cost for the salary of the Technician and the income from the CAR-LIN service flat rate are equal.

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XIX The CAR-LIN service income is directly proportional to the number of patients enrolled, while the technician cost is about 16,000 € /year up to 500 patients, then it doubled because of the need to employ another technician.

Summative Evaluation

As our result suggest, the method proposed in this work could be useful to analyze the RM service from all points of view. The validity of the possible improvements has been demonstrated in the practical application, suggesting a solid and useful design started with on field experience. This method could be effectively extended to all RM services to assess the overall Italian situation including different instrumentation (Biotronik, Boston, St. Jude etc.) for a general comparison of all realities and their practice.

It must be considered that the RM service is an ongoing process strictly dependent from the operator and the making of the activities into practice in each hospital; the analysis carried out in the year 2016 reflects the service performed by the operators, which can be different, especially as regards working timing, if carried out by others.

The patients who do not properly accomplish their task cause a waste of service resources. Reminders and automatic messages could be used to avoid the waste of the operator’s time that could be used to expand the service to other patients; automatic messages are also useful to discuss or confirm the arrival of transmissions.

A possible implementation of digital service resources is the creation an ad hoc database (with the possibility to share it with RM services in other hospitals), with a design that starts from the real needs of operators, in collaboration with the Hospital's ICT service.

The presence of the Color Code would be very useful in contexts of interchanging operators; every new operator will be able to immediately understand the patient's situation, his condition over time and recent pathology development. Cross-referencing this information with the patient's clinical data would provide a better specificity of the guidelines according to the kind of pathology and treatment.

Total real timings of Niguarda Hospital RM service turn out to be very high, but they were measured with completeness, considering all activities related to the service, including

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XX hospital paperwork. The mean number of transmissions made by each patient per year is very high (9 trans*year) compared to the guidelines (2-4 trans*year), proving the operators’ decision to shorten the time between the sending of transmissions.

In the first month of application of charges, patients have willingly accepted the new regulation and the eventual payment of the fee in the absence exemption; the actual measurement of their acceptance degree could be made with the support of questionnaires specifically defined for the RM service.

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XXI

Sommario

Il servizio di Monitoraggio Remoto (RM) è una realtà ormai affermata all'interno degli ospedali italiani e come tale necessita di una descrizione specifica delle attività, delle linee guida precise ed una verifica della messa in pratica del servizio. Un'analisi della situazione, delle risorse a disposizione e dei problemi riscontrati da operatori e pazienti, può portare ad un miglioramento del servizio dal punto di vista pratico, clinico e amministrativo.

Lo scopo del progetto è stato analizzare la situazione attuale delle attività di servizio RM per la gestione delle malattie croniche. Coinvolgendo tutti i possibili soggetti interessati e studiando come il servizio di RM viene effettivamente eseguito nella realtà dell’ospedale Niguardaè possibile avere una visione completa del servizio, i suoi punti deboli e di forza, la cui analisi permette lo sviluppo di nuove idee e proposte per un costante e graduale miglioramento e una maggiore soddisfazione da parte dei pazienti e adeguatezza da parte degli operatori. Tutte le considerazioni e le analisi sono basate sui feedback e i bisogni degli utenti.

Introduzione

La disponibilità di Dispositivi Elettronici Cardiaci Impiantabili (CIED) nella pratica clinica rappresenta un passo cruciale nella cardiologia moderna. Grazie all'efficienza nella cura del paziente scientificamente dimostrata, l'adozione di questi sistemi è in aumento in tutto il mondo. I CIED includono: implantable loop recorder (ILR), pacemaker (PM), implantable cardioverter-defibrillator (ICD), cardiac resynchronization therapy (CRT or CRT-P), cardiac resynchronization therapy and defibrillator (CRT-D or CRT ICD or CRT+ICD). Tecnologie di telemedicina e la trasmissione remota di dati consentono di controllare i parametri tecnici e clinici di un CIED, anche quando il paziente non è in ospedale.

L’AIAC (Associazione Italiana di Aritmologia e Cardiostimolazione) Consensus Conference ha indicato che il RM può integrare e sostituire la tradizionale visita ambulatoriale, senza compromettere la sicurezza del paziente. Il RM porta benefici legati alla cura di alcune patologie (ad esempio la fibrillazione atriale ed insufficienza cardiaca) e la possibilità di monitorare frequentemente il ritmo cardiaco dei pazienti e intervenire tempestivamente durante le terapie farmacologiche. Il RM aiuta a massimizzare l’adeguatezza del consumo delle risorse sanitarie, riservando trattamenti e test diagnostici a

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XXII coloro che ne hanno realmente bisogno. I sistemi di telemonitoraggio automatizzati intelligenti che comunicano quotidianamente bidirezionalmente dal CIED al servizio RM disponibili sul mercato sono: Home Monitoring da Biotronik, CareLink Network da Medtronic, Latitude da Boston Scientific, Merlin da St. Jude e Smartview da Sorin.

Le linee guida ESC (European Society of Cardiology) 2013 attribuiscono al RM, utilizzato per il riconoscimento precoce di problemi clinici e tecnici, la raccomandazione di Classe II e livello di evidenza A, ma numerose testimonianze prodotte dai diversi studi definiscono la Classe IA per il follow-up dei CIED. Nonostante il controllo remoto dei dispositivi sia considerato nella classe IA, non è stato ancora definito un valore economico al servizio. L'AIAC ha sviluppato attraverso la sua Area Telecardiolology un modello organizzativo lineare che è stato raccomandato nelle linee guida dove il flusso di informazioni parte dal CIED del paziente e termina con gli operatori del servizio di RM.

Nell’implementazione pratica del modello, il ruolo dell’infermiera / tecnico di elettrofisiologia consiste in: formazione e educazione del paziente, revisione dei dati e degli allarmi, screening delle trasmissioni e presentazione di casi clinici al medico, contatto con il paziente (telefonate) e consulenza. I compiti del medico sono: raccolta di consenso informato, supervisione e controllo delle trasmissioni, programmazione di dispositivi, mantenere i rapporti con altri specialisti.

Importanti studi clinici hanno dimostrato la superiorità del RM rispetto al controllo tradizionale, in termini di: riduzione delle visite programmate / non programmate e la loro durata, riduzione di accessi in pronto soccorso e ricoveri, individuazione precoce di problemi tecnici e eventi clinicamente rilevanti.

Per quanto riguarda la soddisfazione dei pazienti, il RM evita i costi indiretti a carico del paziente; più del 90% dei pazienti trova RM facile da usare e lo raccomanda, il 78% preferisce il RM alla visita in ospedale e l’83% considera il RM più confortevole.

Metodi

Per trovare la strategia adeguata per condurre l'analisi del servizio RM di Niguarda, è stata eseguita una revisione della letteratura degli articoli che presentano i metodi di progettazione per tecnologie eHealth; sono stati individuati i seguenti approcci: user-centered,

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XXIII multidisciplinare,a partecipazione degli utenti, a valutazione iterativa e a valutazione delle prestazioni.

Questi approcci definiscono l’identificazione degli operatori e il loro continuo coinvolgimento nella progettazione (importanza delle esigenze del paziente), la raccolta di dati qualitativi e quantitativi, un continuo controllo e revisione delle innovazioni e la valutazione della performance attraverso tutti gli aspetti definiti. Per sottolineare l'importanza di ogni tappa, è stato proposto da Van Gemert-Pijnen et al. un approccio olistico che unisce tutti i punti chiave per la descrizione delle tecnologie eHealth.

Il modello è basato su un approccio multidisciplinare di metodi misti per aumentare la cooperazione tra coloro che sono responsabili della produzione della tecnologia o creare e fornire servizi eHealth e coloro che vi partecipano e la usano per garantire che le tecnologie eHealth siano in sintonia con le esigenze e valori definiti. È diviso nelle seguenti sezioni: Inchiesta contestuale e Specifica dei valori, Progettazione, Operazionalizzazione e Valutazioni conclusive.

L'approccio olistico tende a sottolineare l'importanza del tutto e l'interdipendenza delle sue parti, evitando l’analisi separata; per questa ragione abbiamo deciso di adeguare il modello proposto per condurre la nostra analisi.

Inchiesta contestuale e Specifica dei valori

La prima analisi si focalizza sull’organizzazione del servizio: l’equipe iniziale era formata da un cardiologo, un infermiere e un tecnico di elettrofisiologia. Il servizio è stato effettuato nel reparto di Cardiologia 3 - Elettrofisiologia dell'Ospedale Niguarda Ca' Granda. Tutti i pazienti arruolati nel servizio sono portatori di dispositivi impiantabili Medtronic (PM, ILR, ICD-MONO, ICD-BIC, CRT) e usano il monitor Medtronic CareLink. L'osservazione sul campo ha portato alla raccolta diretta dei dati (misurazioni) e la raccolta di dati indiretta, che consiste in alcune interviste agli operatori e consultazione di banche dati. La partecipazione al progetto è volontaria e il servizio è stato inizialmente fornito gratuitamente, senza alcun rimborso dal SSN alla struttura.

Nel mese di dicembre 2016, per un totale di 502 pazienti arruolati, di cui 343 regolarmente seguiti dall’equipe base (1 medico, 1 tecnico), secondo la seguente classificazione: 127 CRT, 115 ICD-MONO, 34 ICD-BIC, 17 PM, 50 ILR.

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XXIV In base alle attività osservate direttamente e il confronto con le linee guida italiane, viene descritto il flusso delle attività: dopo l'impianto, il medico fa firmare il consenso informato e il tecnico arruola, addestra e consegna la tecnologia al paziente che inizia la trasmissione dei dati al centro. Nella data fissata, il tecnico verifica che tutte le trasmissioni siano arrivate e, dopo una prima revisione, presenta i casi clinici al medico che crea il referto; in caso di bisogno il paziente viene convocato per una visita ambulatoriale.

La stima del tempo necessario prima dell'avvento e durante i primi anni di RM a Niguarda basati su esperienze personali degli operatori, in min*anno*paziente, è la seguente:

 TECNICO: arruolamento (0 min; 20 min), pratiche burocratiche (0 min; 5 min), trasmissioni (0 min; 90 min), telefonate (5 min; 30 min), gestione problematiche cliniche (20 min; 0 min), totale (25 min; 145 min);

 MEDICO: arruolamento (0 min; 5 min), pratiche burocratiche (15 min; 5 min), trasmissioni (0 min; 20 min), telefonate (15 min; 5 min), gestione problematiche cliniche (60 min; 30 min), totale (90 min; 65 min);

 OSPEDALE: pratiche burocratiche (30 min; 10 min), totale (30 min; 10 min). I risultati del tempo necessario ai pazienti per le diverse azioni prima e dopo l’avvento del RM sono: arruolamento, (0 min; 20min), pratiche burocratiche (30 min; 10 min), trasmissioni (0 min; 10 min), telefonate (20 min; 35 min), gestione problematiche cliniche (60 min; 25 min), spostamenti (150 min; 60 min), totale (260 min; 160 min).

Un gruppo di 53 pazienti portatori di ICD ha effettuato una media di 2 visite/anno per il 2011, 2012, 2015 e 1 visita/anno per il 2009, 2010, 2013, 2014, 2016, la moda è di 2 visite/anno solo per il 2011, 1 visita/anno per tutti gli altri anni. Nel 2011 (anno di arruolamento) i pazienti hanno effettuato il doppio del numero di visite ambulatoriali, a causa dell'inizio del servizio presso l’ospedale.

Il flusso di informazioni, insieme all'importanza della progettazione centrata sull'utente, dà luogo ad un modello con una struttura circolare in cui il flusso non viene mai interrotto. Il modello, già utilizzato a Niguarda, ha bisogno di una definizione precisa.

Il problema principale riscontrato nel servizio di RM è stata l'ottimizzazione delle risorse: i tempi e la mancanza di database strutturati (dati mancanti, errata classificazione di dati, descrizione insufficiente dei dati, incertezza dei dati). La possibile implementazione dei

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XXV database è la creazione di un sistema di codifica che incrementi l’interoperabilità degli operatori e la strutturazione dei database stessi.

L'assenza di un rimborso effettivo all’ospedale Niguarda porta ad uno svantaggio economico a fronte di un beneficio clinico provato.

Progettazione

La prima proposta di implementazione riguarda il modello di lavoro organizzativo utilizzato in RM: come osservato nell’ospedale Niguarda, il modello ha un flusso circolare di informazioni, in cui la centralità del paziente nella cura delle malattie croniche è evidenziata. Il flusso di informazioni parte dal CIED del paziente e, dopo le attività di RM, torna al paziente stesso.

Per capire le capacità di accettazione e di utilizzo (Digital Health Literacy) che i pazienti hanno nei confronti della tecnologia RM, i dati provenienti da un gruppo selezionato di pazienti portatori di ILR sono stati analizzati. Partendo dalla definizione proposta dalla WHO, la definizione di aderenza è stata contestualizzata per l'uso di un dispositivo ILR nel servizio di RM: percentuale del rapporto tra il numero di trasmissioni puntuali ed il totale delle trasmissioni previste per ogni singolo paziente.

Un possibile obiettivo era quello di migliorare i database, in base alle esigenze degli operatori e sulla base della pratica quotidiana, ad esempio, la creazione di un ‘Codice colore’ da assegnare al paziente, esplicativo della sua condizione e il grado necessario di cura (basato sui referti delle trasmissioni: rosso per l’ospedalizzazione, arancio per le visite ambulatoriali, giallo per un intervallo di trasmissione minore di 3 mesi, verde per un intervallo di trasmissione di 3 mesi, blu per i problemi tecnici, viola per la sostituzione del dispositivo). Il nostro obiettivo è stato assegnare un punteggio al paziente che risulti immediatamente comprensibile da parte dell'operatore e che definisca la situazione generale del paziente, per fornire una prima idea semplificata della sua condizione, prima che l'operatore possa accedere alle cartelle cliniche complete.

Un ulteriore miglioramento è legato ai database telefonate, col fine di creare una migliore definizione dei motivi per chiamate in un database strutturato; sulla base dei principali motivi di ogni chiamata annotati nel campo libero, le ragioni di chiamata ricorrenti e la loro durata sono state identificate come segue:

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XXVI • trasmissioni e batteria (2 min);

• sintomi, programmazione visita, allarme acustico, Optivol (4 min); • altro e problemi tecnici (6 min)

A partire dal giugno 2016, gli operatori del servizio di Niguarda hanno utilizzato nel database la categorizzazione proposta.

La principale risorsa del servizio di RM è il tempo di lavoro degli operatori; un'analisi quantitativa sui tempi effettivamente utilizzati per le attività è stata effettuata. Tale verifica, rispetto a quanto riportato in letteratura, può dimostrare il tempo necessario per la pratica del servizio e definire se ci siano possibili miglioramenti nell’utilizzo di tali risorse. Sulla base dei dati raccolti da marzo 2016 a dicembre 2016 (min*paziente*anno) sono stati misurati:

 TECNICO: addestramento 5 min (20 min da aggiungere per il primo arruolamento), pratiche burocratiche 5 min, trasmissioni 140,8 min, telefonate 18,5 min, totale 169,3 min;

 MEDICO pratiche burocratiche 5 min, trasmissioni 46,9 min, telefonate 5 min, gestione problematiche cliniche 30 min, totale 86,9 min;

 OSPEDALE pratiche burocratiche 10 min, totale 10 min.

Si può notare che, nonostante il tempo totale speso dalla struttura (somma del tempo del tecnico, medico e ospedale) prima e dopo l'uso della RM è aumentato (145 min; 247,7 min), il paziente ha un notevole guadagno di tempo (260 min; 134 min).

Il prezzo seguente è stato identificato nel Tariffario Medicina Specialistica Ambulatoriale ed è stato ritenuto opportuno per la tariffazione base del controllo a distanza dei pazienti portatori di CIED per un anno solare: 89.54 monitoraggio elettrocardiografico telemetria stimato 46,50 euro.

L’adeguamento tariffario proposto, secondo la complessità dei dispositivi differenti RM, è: • 89.54 ECG telemetria di ILR e PM stimato 46.50 EUR

• 89.54.6 ECG telemetria e RM per ICD stimato 56.50 EUR • 89.54.7 ECG telemetria e RM per CRT stimato 66.50 EUR

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XXVII

Operazionalizzazione

Il capitolo consiste nella descrizione dell’attuazione delle proposte progettate nel capitolo precedente.

Sul totale delle trasmissioni effettuate in un periodo di quattro anni da 18 portatori di ILR, la percentuale di trasmissioni in ritardo è stato pari al 14%, con conseguente 86% di aderenza.

Per i 53 pazienti analizzati in 6 anni, il codice colore risultata in:

 TRASMISSIONI NON PROGRAMMATE : 25% verde, 51% giallo, 3% arancio, 0% rosso, 20% blu, 1% viola.

 TRASMISSIONI PROGRAMMATE: 41% verde, 55% giallo, 1% arancio, 0% rosso, 1% blu, 2% viola.

Il punteggio medio ottenuto in modo retrospettivo esaminando le trasmissioni utilizzate per implementare il codice è di 0,6.

Per convalidare la classificazione delle telefonate è stata condotta un'analisi separata della seconda metà del 2016 (b), in cui l'operatore utilizza la nuova classificazione. Il confronto tra la media degli anni dal 2013 al 2016 e la seconda metà del 2016 dimostra che la categoria “altro” è diminuita; questo potrebbe essere legato al fatto che le telefonate sono state ridistribuite in modo più preciso nelle categorie definite (ad esempio trasmissione, sintomi e la pianificazione visita).

L'ambulatorio CAR-LIN è iniziato nel novembre 2016 con la tariffazione precedentemente proposta. Allo stato attuale, con l'equipe di base, l’Ospedale Niguarda sta avviando un progetto pilota sulla nuova tariffazione per seguire un massimo di 500 pazienti nel corso di un anno solare. Alla fine di dicembre 2016, con 343 pazienti arruolati attivi, il costo per lo stipendio del tecnico coincide con il reddito derivante dall’ambulatorio CAR-LIN. L’introito del servizio CAR-LIN è direttamente proporzionale al numero di pazienti arruolati, mentre il costo tecnico è di circa 16.000 € / anno fino a 500 pazienti, in seguito raddoppia a causa della necessità di impiegare un altro tecnico.

Valutazione conclusive

Come i nostri risultati suggeriscono, il metodo proposto in questo lavoro potrebbe essere utile nell’ analizzare il servizio di RM da tutti i punti di vista. La validità delle

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XXVIII implementazioni è stata dimostrata nell'applicazione pratica che suggerisce una proposta di design solida e utile estrapolata dall’esperienza sul campo.

Questo metodo potrebbe essere esteso in modo efficace a tutti i servizi RM della realtà italiana, considerando tutta la strumentazione (Biotronik, Boston, St. Jude etc.), per un confronto generale della pratica complessiva.

Bisogna però considerare che il servizio di RM è un processo in continua evoluzione strettamente dipendente dall’operatore e dalla messa in pratica delle attività all’interno di ogni singolo ospedale; l’analisi effettuata nell’anno 2016 rispecchia il servizio effettuato dagli operatori, che potrà essere diverso, soprattutto per quanto riguarda le tempistiche di lavoro, se effettuato da altri.

I pazienti che non assolvono correttamente il loro compito provocano uno spreco di risorse del servizio. Promemoria e messaggi automatici potrebbero essere impiegati per evitare lo spreco di tempo dell'operatore che creerebbe la condizione per espandere il servizio ad altri pazienti; messaggi automatici sono utili anche per discutere o confermare l'arrivo delle trasmissioni.

Una possibile implementazione di risorse di servizi digitali è la creazione di un database ad hoc (con la possibilità di condividerlo con i servizi di RM in altri ospedali), con un design che parta dalle reali esigenze degli operatori, in collaborazione con il servizio ICT dell'ospedale.

La presenza del codice colore sarebbe molto utile in contesti di intercambiabilità tra gli operatori; ogni nuovo operatore sarà in grado di capire immediatamente la situazione del paziente, la sua condizione nel corso del tempo e lo sviluppo di patologia recente. Incrociare queste informazioni con i dati clinici del paziente fornirebbe una migliore specificità delle linee guida in base al tipo di patologia e del trattamento.

I tempi reali totali di servizio RM dell'ospedale Niguarda risultano essere molto elevati, ma sono stati misurati con completezza, considerando tutte le attività connesse al servizio, tra cui le pratiche burocratiche dell’ospedale. Il numero medio di trasmissioni effettuate da ciascun paziente per anno è molto alto (9 trans*anno) rispetto alle linee guida (2-4 trans*anno), dimostrando la decisione degli operatori di ridurre il tempo che intercorre tra l'invio di trasmissioni.

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XXIX Nel primo mese di applicazione delle tariffe, i pazienti hanno accettato di buon grado il nuovo regolamento e l'eventuale pagamento della quota in assenza di esenzione; la misura effettiva del loro grado di accettazione potrebbe essere realizzata utilizzando questionari specificamente definiti per il servizio di RM

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1

Chapter 1 - Introduction

1.1 Implantable devices

The introduction of medical devices in clinical practice, such as pacemakers and implantable defibrillators, represented a crucial step in modern cardiology over the past decades. Thanks to scientifically recognized increased efficiency in patient care, these systems are being widely used all around the world, and their adoption is increasing. [1].

In fact, nowadays such devices for the electrical cardiac stimulation/defibrillation of the heart and recording of ECG signal allow the specialist to have elements for personalizing electrophysiological treatment, through diagnostic and support functions to create follow-up programs based on the specific needs of the patient.

 Electronic cardiac devices (ECDs) include: Implantable loop recorder (ILR);  Pacemaker (PM);

 Implantable cardioverter-defibrillator (ICD) to provide early defibrillation and cardioversion of life-threatening arrhythmias;

 Cardiac resynchronization therapy (CRT or CRT-P);

 Cardiac resynchronization therapy and defibrillator (CRT-D or CRT ICD or CRT+ICD) that combines functions of CRT-P and ICD devices to both improve the heart’s pumping efficiency and defibrillate the heart internally in case of an acute arrhythmic event.

1.1.1 Implantable loop recorder

An implantable loop recorder (ILR) is a small device implanted under the skin of the chest; it is programmed to continuously monitor the activity of the heart in the form of electrocardiogram (ECG), storing information in its circular memory.

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Abnormal activities such as arrhythmia (irregular heartbeats) are recorded by preserving a segment of the memory for later review. Typically, up to three episodes of abnormal activity can be stored [2], with the most recent episode replacing the oldest. [3]

Recording can be activated in two ways:

 first, recording can be activated automatically according to heart rate ranges previously defined and set in the ILR by the physician. If the heart rate drops below, or rises above, the set rates, the ILR will record without the patient’s knowledge.

 The second way the ILR records is through a hand-held "patient activator" whereby the patient triggers a recording by pushing a button when he notices symptoms such as skipped beats, lightheadedness or dizziness. [w1]

The ILR records by preserving the electrical information preceding, during and after the symptoms in the format of an electrocardiogram. [3]

The physician can download and review the recorded events during an office visit. [w1]

Figure 1 Medtronic REVEAL LINQ [w2]

The ILR is a small, rectangular device (Figure 1) that measure 62x19x8 mm and weight 17g. [3]

A pair of built-in sensing leads located in the shell of the device allows for recording of a single lead bipolar electrogram, which can be downloaded via radiofrequency with a special

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programmer. The device is usually implanted into the subcutaneous tissue in the left pectoral area under local anesthesia; current devices have an estimated battery life of 36 months.[w2]. Some devices include an algorithm for atrial tachycardia and atrial fibrillation detection based on irregularities in RR intervals.

1.1.2 Pacemaker (PM)

The PM is a medical device capable of obviating the cases of cardiac arrhythmia consisting of too slow or irregular heartbeats (bradycardia). The pulse generator, interpreting the patient ECG signals registered from the leads, transmits electrical impulses to the cardiac muscle, taking into account the patient's pathological profile.

In 1889, John Alexander McWilliam reported his experiments in which the application of an electrical impulse to the human heart in asystole caused a ventricular contraction, and that a heart rhythm of 60–70 beats per minute could be evoked by impulses applied at pacings equal to 60–70/minute [4].

In 1932, American physiologist Albert Hyman, described an electro-mechanical instrument of his own, powered by a spring-wound, hand-cranked motor. Hyman himself referred to his invention as an "artificial pacemaker", the term continuing in use to this day [5].

Figure 2 Hyman design of the first “artificial pacemaker” [5]

The first clinical implantation into a human of a fully implantable PM was in 1958 at the Karolinska Institute in Solna, Sweden, using a PM connected to electrodes attached to the myocardium of the heart by thoracotomy. The device failed after three hours.

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The world's first implanted PM patient, Arne Larsson, went on to receive 26 different PMs during his lifetime. He died in 2001, at the age of 86, outliving the inventor as well as the surgeon [6].

Cardiothoracic Surgeon Leon Abrams, and Medical Engineer Ray Lightwood, developed and implanted the first patient controlled variable rate heart PM in 1960 at Birmingham University [w3].

Figure 3 Representation of Abrams PM [w3]

Currently, although various types are available, artificial PM devices generally include the same following components:

 a thin metal box or case called a pulse generator, which contains the power source producing the electrical impulses of the PM. In addition, the pulse generator contains a small computer processor that can be programmed to set the rate of the PM, the pattern of pacing, the energy output, and various other parameters. The pulse generator for most modern permanent PMs weighs 28 to 56 g;

 flexible insulated wires or leads to carry electrical impulses from the generator to the heart muscle, and to relay information concerning the heart's natural activities back to the PM. There may be several of such wires, or leads, placed within the heart, most commonly in the right atrium and right ventricle. Only one type of PM is “leadless” and does not have any wires;

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 the pacing lead most commonly incorporates one or two electrical "poles." An electrical impulse is transmitted to the heart muscle when needed, and the lead is also able to sense the heart's intrinsic electrical activity.

Figure 4 PM Medtronic Advisa MRI SureScan PM [w2]

Varieties of types of PMs and modes of pacing have been developed to restore or sustain a regular heartbeat in different ways. All contemporary PMs sense the intrinsic activity and stimulate the heart only when the intrinsic heart rate falls below the programmed pacing rate. Essentially all contemporary PMs also incorporate rate responsive capability, based on a "sensor" incorporated into the PM that can sense activity or respiratory rate and can alter the heart rate (HR) based on the perceived physiologic need.

Pacemakers may also be single, dual, or triple chambered:

 single-chamber PMs have one lead to carry impulses to and from either the right atrium (RA) or right ventricle (RV);

 a dual-chamber PM characteristically has two leads, one to the RA and one to the RV, which can allow a heart rhythm that more naturally resembles the normal activities of the heart and reflects intrinsic depolarization;

 triple-chamber PMs typically have one lead in the RA, one to stimulate the RV, and one to stimulate the left ventricle (LV). These devices are used in patients who have a weakened heart muscle (thus resulting in heart failure). These PMs "resynchronize" the ventricles and may improve the efficiency

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of the contraction of the heart. They are also commonly referred to as "biventricular pacemakers."

The PM is most commonly implanted into soft tissue beneath the skin in an area below the clavicle, known as prepectoral implantation; this is located under the skin and fat tissue but above the pectoral muscle. The PM leads are typically inserted into a major vein (transvenously) and advanced until they are secured within the proper region(s) of the heart muscle. The other ends of the leads are attached to the pulse generator. Less commonly, the pulse generator is placed under the skin of the upper abdomen.

People who have a permanent PM will require periodic monitoring of the implanted device. The PM status will be regularly checked or "interrogated" (often done remotely using a telephone or a secure web-based system) to provide information regarding the type of heart rhythm, the performance of the PM leads, the frequency of utilization, the battery life, and the presence of any abnormal heart rhythm. The pulse generators are usually powered by lithium batteries that function for an average of five to eight years before they need to be replaced.

All contemporary devices are programmable with information and settings that can be changed and stored. Information is obtained by transmitting data from the pulse generator to a programmer, usually done during a follow-up office visit. However, with newer pulse generators it may be possible to obtain information about the PM’s performance by downloading data from the patient's device to the internet and then to the caregiver's office.

1.1.3 Implantable cardioverter device (ICD)

The ICD is a life-saving device that is implanted in categories of patients at high risk of ventricular tachyarrhythmias (VTs). The treatment consists in providing defibrillation therapy, cardioversion and antitachycardia pacing. Furthermore, the device is able to store information that can be analyzed by the physician in the course of the monitoring visit. The development of the ICD was pioneered at Sinai Hospital in Baltimore and similar developmental work was carried out almost coincidentally at the University of Missouri [7]. More than a decade of research resulted in the development of an ICD that would automatically sense the onset of ventricular fibrillation (VF) and deliver an electric

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countershock within 15–20 seconds, converting the rhythm to sinus rhythm. Improved versions were programmed to be able to detect VT, often a forerunner of VF. These were then called implantable cardioverters. Dr. Levi Watkins, Jr. implanted the first device in February 1980 at Johns Hopkins Hospital [w4].

The ICD includes the following components:

 the pulse generator houses a battery and a tiny computer; energy is stored in the battery until is needed and the computer receives information from the leads to determine what rhythm is occurring;

 lead(s) consists of wire(s) that send(s) impulses from the pulse generator to the heart muscle, as well as sense(s) the heart’s electrical activity; each impulse causes the heart to contract.

The ICD is indicated in patients with high risk of cardiac arrhythmias, in which the device is typically under stand-by condition and acts to restore normal heart rhythm when life-threatening arrhythmias occur. The ICD can automatically detect both ventricular (VT/VF) and atrial tachyarhythmias (AT/AF), delivering therapies using a shock (defibrillation/cardioversion) or rapid ventricular pacing to stop the arrhythmias. During the shock, the ICD delivers the energy required to reset the heart muscle restoring a normal cardiac rhythm. The ICD also reacts to bradyarrhythmias using pacing therapies (if the heartbeat is less than a predetermined value, the device stimulates with an appropriate rate). In addition, the device records any electrical event that may have happened and can be

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interrogated, thus being able to provide diagnostic information and monitoring, useful for the evaluation of the system and the clinical treatment of the patient. The ICDs can be divided mainly in 3 categories:

 single chamber ICDs  dual chamber ICDs

 CRT-ICDs: single-chamber ICDs have only an RV lead, while dual-chamber ICDs have RA and RV leads, and an additional lead placed on the epicardium or via the coronary sinus to stimulate the LV [8].

ICDs are programmed through an external computer (programmer) located in an ambulatory or hospital setting to set the device according to the specific patient’s necessity, transmitting information previously through a telephone line, now wirelessly.

ICDs constantly monitor the rate and rhythm of the heart and can deliver therapies, by way of an electrical shock, when the heart rate exceeds a preset number. More modern devices have software designed to attempt to discriminate between VF and VT, and may try to pace the heart faster than its intrinsic rate in case of VT, to try to break the tachycardia before it progresses to VT. This is known as overdrive pacing, or anti-tachycardia pacing (ATP). ATP is only effective if the underlying rhythm is VT, and is never effective if the rhythm is VF. Rate discrimination evaluates the rate of the lower chambers of the heart (the ventricles) and compares it to the rate in the upper chambers of the heart (the atria). If the rate in the atria is faster than or equal to the rate in the ventricles, then the rhythm is most likely not ventricular in origin, and is usually more benign. If this is the case, the ICD does not provide any therapy, or withholds it for a programmable length of time.

Rhythm discrimination will see how regular a VT is. Generally, VT is regular, but if the rhythm is irregular, it is usually due to conduction of an irregular rhythm that originates in the atria, such as atrial fibrillation (AF). In the Figure 6, an example of torsade de pointes can be seen; this represents a form of irregular VT. In this case, the ICD will rely on rate, not regularity, to make the correct diagnosis.

Morphology discrimination checks the morphology of every ventricular beat and compares it to the morphology of normally conducted ventricular impulse for the patient. This normal

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ventricular impulse is often an average of a multiple of normal beats of the patient acquired in the recent past and known as a template.

The integration of these various parameters is very complex, and clinically the occurrence of inappropriate therapy is still occasionally seen and a challenge for future software advancements.

Figure 6 Lead II ECG showing Torsades being shocked by an ICD back to the patient's baseline cardiac rhythm [w5]

1.1.4 Cardiac resynchronization therapy (CRT)

Cardiac resynchronization therapy (CRT) with biventricular pacing is a treatment for heart failure (HF) consisting of the use of an implantable device that restores the proper synchronization of the two ventricles by sending electrical impulses to the heart chambers.

Figure 7 CRT-D implant [w2]

CRT is an evolution of PM, thus providing strategic electrical stimulation to RA, RV and LV to coordinate ventricular contractions and improve cardiac output in patients with

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ventricular asynchrony. This is commonly associated with HF. The primary objective of CRT is the restoration of a normal ventricular activation pattern; moreover, CRT allows the optimization of the atrio-ventricular interval in patients with sinus rhythm [9]. A cardiac resynchronization pacemaker without ICD capability (CRT-P) is used in patients with ventricular dysfunction who are not candidates for an automatic cardioverter-defibrillator-type device. Cardiac resynchronization therapy and defibrillator (CRT-D) combines ICD and CRT-P.

Figure 8 Medtronic Amplia, Compia CRT-D Secure-Scan [w2]

Battery life is an important characteristic because longer duration means prolonging the time before device replacement or re-implant, reducing costs and risks of surgery for the patient [10]. The battery status can be detected by telemetry or by programmer. Finally, models can differ also by their year of commercialization due to the very dynamic CRT-D market. This is reflected by a model turnover of one year. The rapid technical development of CRT and CRT-D devices in the last decade has introduced difficulties in their assessment, as comparative analysis must be made comparing like devices. Some of the patients to which this document refers have received submodels of apparently the same device, or different devices with different functionalities.

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1.2 European spreading of devices

In the last few years, implantable medical devices have become a fundamental resource in the care of heart problems. This observation is supported by statistics regarding the spread of the implants in Europe, in particular from 2010 of Medtronic devices.

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As for PM, Italy is in third place in Europe by number of implants per million inhabitants, trailing only Germany, Belgium and Luxembourg, with a gradual increase of the implants over the years, slightly above the European average.

Also from the point of view of ICDs, Italy is slightly above the average with a linearly increasing trend over the years. Surprisingly, Germany’s first place total is roughly twice that of the European average.

As for CRT-P and CRT-D, there are obvious differences between the two devices; in the first case Italy is, albeit slightly, for the first time below the European average as opposed to other states that follow a diametrically opposite trend (PM systems and ICD below average and high values of CRT-P). From the graph of CRT-D, Italy is again above average and ranked second after Germany.

1.3 Control of implantable devices

Thanks to advances in technology, today’s PM, ICD and CRT devices can operate mainly in automatic mode. The growing number of patients with implants and the consequent increase in the number of controls that patients have to undergo periodically determine an equally increasing consumption of resources among the electrophysiology ambulatory (mainly in terms of person-time).

The first telemedicine systems were born in the 70s but only after 2000 did the use of a remote control for ICDs begin [11-12-13]. In recent years, several work-flow processes able to improve the management of patients with implanted ICD have been designed and developed: from a monitoring focused primarily on the device, the attention has been moved mainly to the patient, thanks to the integration and monitoring of additional functional parameters. Integration with telemedicine technologies - and therefore of remote data transmission - allows the control of technical and clinical parameters of a medical device, even when the patient is not at the hospital. To conduct follow-up after implantation, the specialist today can choose between two different methods of execution:

a. Traditional (outpatient, hospital);

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In the traditional mode, the follow-up is performed at an outpatient clinic in programmed dates, where the device is interrogated by telemetric radio-frequency, thus requiring the physical presence of the patient, the doctor and the technical and nursing staff.

The timing of the controls, according to the main guidelines [16], include:

1. testing the device shortly after the intervention for its positioning, focused on the evaluation of possible surgical complications, location of the leads and the device’s proper performance;

2. testing the device from 1 to 4 times a year, depending on the type, where in addition to its integrity, the therapeutic response of the patient is evaluated;

3. increasing the frequency of examinations approaching the battery "end of life" or in the event of any problems related to the device operational status.

During this evaluation, the operational parameters of the system are analyzed, thus obtaining information on both the status of the implanted device and on the patient's health.

These parameters allow the specialist electrophysiologist to perform an assessment of the adequacy of the programming for the individual patient and the adequacy of the drug therapy in progress, as well as of the whole clinical picture.

Electronic control (remote follow-up) can replace the periodic planned ambulatory visit. In fact, the guidelines of the ISHNE (International Society for Holter and Noninvasive Electrocardiology)/ EHRA (European Heart Rhythm Association) Expert Consensus [14] for ambulatory monitoring of the holders of implantable devices and the Consensus Conference of AIAC (Associazione Italiana di Aritmologia e Cardiostimolazione) [17] indicated that the remote control can supplement and / or replace in all aspects the traditional ambulatory monitoring without compromising patient safety [14-15].

The telecommunication networks (both home and mobile) are used in remote control for transmission of the operational device data; such communication takes place automatically from the device itself through a "Communicator" connected (in wireless manner) with the implanted device (PM / ICD generator) [16].