A new solution for a Heart Failure Monitoring system based on Wearable and Information Technologies E. Villalba1, M. T. Arredondo1, S. Guillen2, E. Hoyo-Barbolla1 1: Life Supporting Technologies, Technical University of Madrid, Spain 2: Health & Wellbeing Technologies R&D group, ITACA Institute, Spain
[email protected]
Abstract Cardiovascular diseases (CVD) are the leading source of death in the western world and in particular, in Europe CVD cause 45% of all deaths. Besides, Heart Failure (HF), the paradigm of CVD, affects mainly people older than 65. Facing this reality, the European Union funded MyHeart Project, whose mission is empowering citizens to fight CVD by means of a preventive lifestyle and an early diagnosis. This paper presents an innovative integrated solution for the assessment of Heart Failure: HF Management (HFM). HFM is a Heart Failure Disease Management System that makes use of innovative approaches, based on Information Technologies (IT) and wearable technologies, for the continuous assessment of HF progression and cardiovascular risk stratification. By integrating patient data from different sources with special emphasis in the information obtained from extensive ECG processing the system assesses the patient’s cardiac condition. Rather than just merely evaluating the cardiovascular status, HFM is designed to motivate patients to acquire an active role in their health management and to help them to improve their cardiac condition by promoting physical exercise.
1. Introduction Heart Failure is a relative common chronic disorder which mainly affects people older than 65 [1]. In developed countries, population life expectancy is increasing; causing a growth of rehospitalizations due to chronic diseases and a decrease in the quality of life.
with selected information, allowing the evaluation of symptoms progression, arrhythmic and ischemic risk with the aim of preventing possible rehospitalizations due to clinical destabilizations. The main objective of the system presented is to make use of technology and procedures to improve the outcomes, both mortality and morbidity, of HF population. The system also aims at improving the efficiency of the healthcare resources, maximizing the cost-benefit of the heart failure management. The scenario proposed is the supervising of short walks for the monitoring of HF related biomedical parameters (e.g. ECG, respiration and level of activity) and the motivation of key patients’ by means of the devices used. The data collected are processed and used in the detection of functional capacity worsening and ischemia complications. The evolution of the data with time is automatically assessed in order to enable the early detection of possible clinical decompensations (clinical destabilization warning signs), the continuous out of hospital arrhythmia risk stratification and the evaluation of HF progression. On the other hand, motivation strategies have been carefully studied in order to provide patients with pertinent and relevant information according to their situation and needs. There are two main stakeholders that benefit directly from using the system: HF chronic disease service management providers, such as cardiologists and nurses; and patients with HF. Figure 1 shows the monitoring process, that consists of four main elements:
The use of new heart monitoring technologies and specialized processing based on Wearable and Information Technologies, provides professionals
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be treated keeping the same quality level of assistance (100% affirmative). According to the responses analyzed, the system will contribute to motivate the patients and raise their awareness of the importance of taking control of their healthcare to do controlled exercise and their confidence in managing their pathology in a correct manner, which will directly improve their quality of life.
Fig. 1. System Overview •
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The Front-end, composed of the different garments, textile sensors and electronics for the recording of the vital signals that are demanded by the application (ECG, respiration and activity level). The patient station, which is based on a personal digital assistant device that receives information from the monitoring program and encourages and motivates the patients in the daily care of their heart. The Server, which is the core processing element. All the patients’ data gathered during walk sessions are regularly sent by the patient stations to be processed. The Professional station that provides direct access to the application through a web-based interface provided by the server.
2. Methods A preliminary “mock-up” version of the system was thoroughly validated during 3 months by the main stakeholders involved: end-users, business managers and medical specialists. The validation was based on personal interviews with questionnaires including open and close-ended questions followed by a system demonstration, in order to allow the users validate the system usability and comfort. In total, 26 people were interviewed: 10 end users (9 men and 1 woman, 80% of them above 60 years), 6 business managers and 10 cardiologists. The analysis of the preliminary validation has proven to be very positive. Regarding the confidence the system generates in users, the analysis of the responses shows a very positive outcome (95% affirmative). Furthermore, the system is believed to be a booster of the healthcare system productivity, as business managers conclude, that more patients could
The study unveiled that the selected patient device needed to be adapted in order to make it more userfriendly for the elderly users. Furthermore, it was argued that the garment fabrics need to be adaptable to temperature changes, as some patients may have confort problems in wearing tight clothes. The most valued features of the system were the possibility to contribute to the prevention of new rehospitalizations, the patient motivation to treatment compliance and daily exercise and, finally, the avoidance of possible critical events, all of them having effects in a global healthcare reduction of the overall healthcare system costs. From the point of view of the business managers and the medical professionals, the proposed application will open up a completely new market of user-centered preventive personal healthcare, in which Europe could hold a leading position. Having analyzed the results obtained from the evaluation and validation process described above, and after a revision of the changes suggested, an integrated working version of the system has been developed.
3. Results The system has been completely developed following an open architecture based on XML and Web Services [2] in order to allow further scalability. Furthermore, the system is integrated in a content manager such as the Cocoon Framework [3] resulting in a distributed system. The main characteristics or the different elements are presented in Figure 2 and described in the following sections.
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Some screens of the Patient Station are presented in Figure 3.
Fig. 3. Patient station layout
3.3. The Server Fig. 2. The System Components
3.1. The Front-end Module The Front-End is formed by different garments [4], sensors and electronics which are required for the recording of the following biomedical signals: 1 lead ECG, Respiration, Bio-impedance and Activity. A stretched t-shirt, denominated MyTShirt [5] has been designed to integrate the required sensors for an adequate monitoring process. This garment can be worn during any season of the year, it is available for both men and women and furthermore and it is transpirable and washable. Due to the impossibility of using conductive gel in a garment, the application requires the use of dry ECG electrodes.
The server is the core processing element of the HFM application. All the patient data collected during the walks are transferred by the patient stations to the server which provides processing and storage capabilities. Moreover, the server provides a webbased interface through which health care professionals are able to access application configuration and patients’ data visualization functionalities. The server has four different functionalities: • • •
3.2. The Patient Station The Patient Station is an assistive mobile device. For the purpose of the project an HP Compaq iPAQ PDA was chosen, since it is compliant with all the technical requirements, such as Bluetooth and GSM module for enabling connectivity to GPRS networks, which offers “always-on” access to Internet-based content and data services world-wide. This assistive mobile device is known as MyDevice in the context of the HF Management application, which will be used by the patient for the walking sessions. The device provides with user interfacing, processing and communication capabilities, both between the Front-end-Patient Station and Server.
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A processing module to handle the ECG and the patient data (i.e. Questionnaires) received from the Patient Station. Storage of all the data in a database which includes the monitoring session data, the patient data, the clinical history, treatments, etc. Following a healthcare protocol defined by the medical team involved, the system creates notifications of a worsening situation for professionals. Web application for the professional interaction, which allows them to manage the patient related data, receiving notifications; and visualizing all recorded and processed data from of all patients.
Besides, it also grants a secure access, user login administration and data privacy and confidentiality. The server architecture was designed as a well integrated system in the common access platform within Myheart [5], with a secure access, user login administration (based on LDAP technology), data privacy and confidentiality, communication services, such as SMS sending; and a web application for the interaction.
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3.4. The Professional Station The Professional Station is a PC-based workstation, implemented with the Cocoon Framework and the CFORM [3] based visualization. As all the professional interaction functionality is accessed through a web-based interface offered by the server, no specific software requirements are demanded for the stations, except that they are equipped with an adequate Internet browser. Figure 4 presents the entry screen to the Professional Station.
We strongly believe this kind of systems will constitute an important part of the life of the citizens of the future, supporting a better Quality of Life and helping in the prevention and treatment of chronic diseases in a real contribution to a better world.
5. Acknowledgements The “My HF Management” work is a complete integrated system part of the MyHeart project, “Fighting Cardiovascular Diseases by prevention and early diagnosis” (IST-2002-507816). MyHeart is a 6th Framework Project of the IST programme, partly funded by the European Commission.
6. References [1] World Health Organization. The Atlas of Heart Disease and Stroke. Edited by J. Mackay and G. Mensah, 2004. [2] Web Services Essentials. By Ethan Cerami. Publisher: O'Reilly. Pub Date: February 2002. ISBN: 0-596-00224-6. [3] Cocoon: Building XML Applications. Matthew Langham Carsten Ziegeler. Publisher: New Riders Publishing. 1st Edition July 19, 2002. ISBN: 0-7357-1235-2.
Fig. 4. Professional Station
4. Discussion and Conclusions As far as the system has been validated, the positive technical results are really encouraging to continue the work and the developments that have been implemented since the evaluation was performed. In particular, it has been shown how connectivity through the Internet and Web Services works as it was planned. Besides, user interaction has been improved (the look and feel of the user Interface, the avatars, etc), according to the information extracted from the validation of the “mock-up”, empowering user adherence to the system.
[4] Wealthy: Smart Clothes for the monitoring in real time and conditions of physiological, emotional and sensorial reactions of human. F. Axisa, A. Dittmar, G. Delhomme IEEE EMBS International Conference 2003, Cancun. [5] Deliverable 6, 7: Application concepts and Technical Progress, MyHeart IST-2002-507816, January 2005. Address for correspondence Elena Villalba Mora Life Supporting Technologies ETSI Telecomunicación. B-303-1 Ciudad Universitaria s/n. Madrid 28040. e-mail:
[email protected] Tel. +34915495700 ext 3407 / Fax: +34913366828
Nevertheless, more studies about security issues need to be carried out, since it is a critical part of the system. Moreover, there are still pending better solutions with the Bluetooth to make the system connectivity completely transparent to the user. Future work encompasses a complete technical revision and clinical trials and the implementation of more algorithms that will enhance the functionality provided to the users.
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