IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS, VOL. 27, NO. 4, MAY 2009 537 Novel Methods of Faster Cardiovascular Diagnosis in Wireless Telecardiology Fahim Sufi, Qiang Fang, Ibrahim Khalil, and Seedahmed S. Mahmoud Abstract—With the rapid development wireless technologies, mobile phones are gaining acceptance to become an effective tool for cardiovascular monitoring. However, existing technologies have limitations in terms of efficient transmission of compressed ECG over text messaging communications like SMS and MMS. In this paper, we first propose an ECG compression algorithm which allows lossless transmission of compressed ECG over bandwidth constrained wireless link. Then, we propose several al- gorithms for cardiovascular abnormality detection directly from the compressed ECG maintaining end to end security, patient privacy while offering the benefits of faster diagnosis. Next, we show that our mobile phone based cardiovascular monitoring solution is capable of harnessing up to 6.72 times faster diagnosis compared to existing technologies. As the decompression time on a doctor’s mobile phone could be significant, our method will be highly advantageous in patient wellness monitoring system where a doctor has to read and diagnose from compressed ECGs of several patients assigned to him. Finally, we successfully implemented the prototype system by establishing mobile phone based cardiovascular patient monitoring. Index Terms—Faster ECG transmission, Heart Rate calcu- lation, Faster Cardiovascular Diagnosis, MMS, SMS, HTTP, Doctor Patient Communication. I. I NTRODUCTION T HE ELECTROCARDIOGRAM (ECG) plays a key role in cardiac patient monitoring and diagnosis. In the in- dustrialized world, it is estimated that millions of people die due to various coronary heart disease annually. The key to treat these diseases is timely detection. Since ECG is the most commonly recorded signal in the patient monitoring and examination process, it becomes important to be able to reliably and quickly detect cardiac diseases from ECG analysis. The use of Mobile Phones and wireless capable Personal Digital Assistants (PDAs) have grown rapidly for various applications over the past decade. More recently, it is en- visaged to provide healtcare solutions for acute, chronic and disaster affected patients [14], [26], [24]. One of the crucial benefit of mobile phone based remote health monitoring is the flexibility and mobility offered by the usage of existing Manuscript received 30 July 2008; revised 11 February 2009. Fahim Sufi is with Science, Engineering & Technology Portfolio, RMIT University, VIC, 3000, Australia. He is also working in Health Informatics division of McPherson Scientific (e-mail: research@fahimsufi.com). Qiang Fang is with the School of Electrical and Computer En- gineering, RMIT University, Melbourne, VIC, 3000, Australia (e-mail: John.fang@rmit.edu.au). Ibrahim Khalil is with the School of Computer Science and IT, RMIT Uni- versity, Melbourne, VIC, 3000, Australia (e-mail: ibrahimk@cs.rmit.edu.au). Seedahmed S. Mahmoud is with Future Fibre Technologies, Mulgrave, VIC, 3170, Australia (e-mail: smahmoud@fft.com.au). Digital Object Identifier 10.1109/JSAC.2009.090515. wireless communication protocols for transmission of health information. In a typical telecardiology application, as shown in Fig. 1, ECG signal is transmitted from the patient to the medical server as well as the doctor via different wireless protocols like SMS, MMS, HTTP and other custom socket routine. Mobile phone is utilized as a signal transmitter and receiver by both patient and doctor. Apart from mobile phones usage as a standard communication device, it has demonstrated its capability of being used to perform ECG analysis like HR detection and RR Interval calculation as demonstrated in our earlier efforts [24]. HR detection is the preliminary step for detecting many of the cardiological abnormalities like Heart Rate Variability (HRV) and different kinds of Arrhythmias. However, despite the obvious prospects of telecardiology, the following challenging issues must be addressed for its successful deployment: • Efficient transmission and Storage: Physiological signals like, ECG, Electroencephalogram (EEG), Blood Pressure (BP), Pulse (P), Blood Oxygen Level (SPO2), PPG etc. during a real-time telemonitoring can grow to a massive amount of 13 GB within 24 hours. In fact, ECG data alone from a signle patient can easily reach up to 2.77 GB in one day. Transmission and storage of this enormous amount of data is a major hurdle for real- time telemonitoring. Application of data compression can mitigate this problem to a certain extent. For wireless telecardiology applications using messagaing protocols, any compression scheme must use the limited character sets available in MMS and SMS protocols in order to avoid any data loss. Reduced data size reduces the cost of ECG transfer via SMS/MMS which is essential for wireless telecardiology to be effective. • Fast detection of abnormalities: To ascertain the heart rate from the compressed ECG signal, the compressed ECG requires to be decompressed first before any further com- putations. This decompression time on mobile devices could be significant. In the scenario as depicted in Fig. 1 both the doctor and medical server receive patients ECG, which is then analysed for any possible abnormalities. In case of abnormalities, life-saving measurements are taken. Therefore, minimizing delays in patient diagnosis is a crucial and highly prioritized research area in both medical and technical domain, since time is life for the patient [12], [14]. The motivation of this paper are the challenges outlined above, and we address them by proposing a novel SMS/MMS compatible lossless compression scheme, and HR detection 0733-8716/09/$25.00 c  2009 IEEE