IEEE TRANSACTIONS ON INFORMATION TECHNOLOGY IN BIOMEDICINE, VOL. 5, NO. 3, SEPTEMBER 2001 253 Real-Time ECG Transmission Via Internet for Nonclinical Applications Alfredo I. Hernández, Fernando Mora, Guillermo Villegas, Gianfranco Passariello, and Guy Carrault Abstract—Telemedicine is producing a great impact in the monitoring of patients located in remote nonclinical environments such as homes, elder communities, gymnasiums, schools, remote military bases, ships, and the like. A number of applications, ranging from data collection, to chronic patient surveillance, and even to the control of therapeutic procedures, are being implemented in many parts of the world. As part of this growing trend, this paper discusses the problems in electrocardiogram (ECG) real-time data acquisition, transmission, and visualization over the Internet. ECG signals are transmitted in real time from a patient in a remote nonclinical environment to the specialist in a hospital or clinic using the current capabilities and availability of the Internet. A prototype system is composed of a portable data acquisition and preprocessing module connected to the computer in the remote site via its RS-232 port, a Java-based client–server platform, and software modules to handle com- munication protocols between data acquisition module and the patient’s personal computer, and to handle client–server communication. The purpose of the system is the provision of extended monitoring for patients under drug therapy after infarction, data collection in some particular cases, remote consultation, and low-cost ECG monitoring for the elderly. Index Terms—ECG monitoring, home monitoring, internet telemedicine, telemedicine. I. OVERVIEW OF TELEMEDICAL APPLICATIONS FOR NONCLINICAL ENVIRONMENTS Technology can be used to improve the quality of life of the people, but, in particular, the elderly, those with varied handicaps, patients in the process of recovery, and any individual that requires access to pe- riodical medical checkups. A well-applied technology improves effi- ciency and effectiveness, lowering costs, saving time, and increasing direct attention to the people. In the case of the elderly and physically handicapped, these aims gain great interest due to the increment in the expenses of medical care in direct proportion to age and disability [1]. The question then becomes, how to reduce cost, while at the same time improving the services, lower the length of hospital stays, bring medical attention to the home in those noncritical conditions, keep a constant surveillance of patients in their homes, and how to make the individual an active participant in the delivery of his/her health care. Currently, the availability of quite sophisticated telecommunication systems is making the global aim of providing all individuals with ac- cess to advanced communication, information, and control systems that improve their life conditions a reality [2], [3]. This leads to the change in conceptual design of healthcare delivery systems. In the case of re- mote monitoring in nonclinical environments, a new model of health delivery that begins with the user is being experimented. There is a shift from episodic intra-hospital medical care, to self-managed, per- manent, and remote personal care, which creates new relationships be- tween users and service providers, and new challenges in the deploy- ment of machine intelligence and in the design of low-cost and, at the Manuscript received July 18, 2000. This work was supported in part by the Universidad Simón Bolívar under Decanato de Estudios Profesionales. A. I. Hernández, F. Mora, G. Villegas, and G. Passariello are with the Grupo de Bioingeniería y Biofísica Aplicada, Universidad Simón Bolívar, Caracas 1080, Venezuela. G. Carrault is with the Laboratoire Traitement du Signal et de l’Image, Uni- versité de Rennes I, Rennes 35042, France. Publisher Item Identifier S 1089-7771(01)04234-0. same time, versatile, and reliable remote units. Fig. 1 describes some of the components of such systems. Its possible to observe the need for the development of intelligent and remotely configurable data acquisi- tion devices at a patient’s side, as well as reliable intelligent agents, or telemedical information systems [2], at both ends of the system. II. CONSIDERATIONS IN ELECTROCARDIOGRAM TRANSMISSION AND MONITORING VIA INTERNET Electrocardiogram (ECG) transmission has been around for quite some time and it has been particularly useful for pacemaker follow-up [4], [5] and other patient monitoring applications [6]. The use of ECG transmission for emergency settings has been emphasized in order to reduce response time in infarct size control or resuscitation of sudden cardiac-death victims [6]. In recent years, the development of the In- ternet has opened a new transmission medium that provides access to many computer centers all over the world at very low costs, and due to its intuitiveness and ease of use, Internet applications, such as world-wide-web (WWW) navigation, have become quite popular. ECG monitoring through the Internet can be of great interest in the follow-up of out-of-hospital patients receiving drugs in order to as- sess efficacy of therapy and potential harmful conditions to the heart. Data-collection protocols at home or care institutions can also be car- ried out for data logging purposes, particularly to provide low-cost ECG monitoring for the elderly. With the help of intelligent agents, consultation sessions can be greatly enhanced and costs lowered. Data sharing among specialists and database acquisition for research pur- poses can also be implemented. This paper presents an Internet-based ECG telemonitoring system, which has been developed as an instance of the general client–server architecture presented in Fig. 1. The data acquisition module (DAM) is a hardware device that allows acquisition and transmission of biomed- ical data from the remote patient to his/her personal computer (PC) or a personal digital assistant (PDA). It contains two main sections: a com- munication section and an application-specific section. In the commu- nication section, a microcontroller handles data compression and the communication protocol established with the PC or PDA. Communication between the patient and specialist is done through a typical client–server architecture. Again, the implementation of both client and server applications is based in a common two-layer design. The first layer implements the communication and control shell, and the second one is adapted to specific clinical applications. The communication and control shell provides the following fea- tures: • user interface (GUI) shared by all the sub-applications; • all common communication services, like connection control, chat, and video; • DAM control and the communication protocol; • transmission of biomedical signals and device commands; • low-level control services. The second layer includes an application-specific object collection that defines the particular graphic interface required for different clin- ical applications, as well as the data analysis, signal processing, and/or signal annotation methods. Real-time ECG transmission via the Internet has been previously re- ported elsewhere [7], [8] in order to provide direct access to physicians in remote locations to coronary-care-unit patient-monitoring data and to check patients being monitored at their homes. This paper describes a complete real-time ECG telemonitoring system, including the signal acquisition hardware, client, and server applications, and the required 1089–7771/01$10.00 © 2001 IEEE