ECG (electrocardiogram) is very essential component for the doctors to diagnose the state of patient’s cardiovascular system. In critical situations doctors may need to examine ECG of patient instantly to take a firm and better decision in their absence near patient. In this paper a better way of instant ECG datatransfer, processing and display is demonstrated. Here ECG is acquired using simple 3 electrode single lead configuration then it is digitized and transmitted to Android smart phone in SMS message format. This SMS data is a bundle of values representing digital ECG. Acquired SMS data is fetched from inbox of the phone and processed for calculation of heart rate and detection of arrhythmia by Android application software. Then ECG is displayed on phone screen along with conclusion of heart rate and arrhythmia (if any).

1. International Journal For Research & Development in Technology
Volume: 2, Issue: 1, JULY-2014 ISSN (Online):- 2349-3585
27
Copyright 2014- IJRDT www.ijrdt.org
Instant Elelectrocardiogram Monitoring in Android Smart Phones Chetan N Betageri 1, Dr V. Udayashankara 2 1 Research Student, Department of Biomedical Signal Processing and Instrumentation 2Professor and Head, I.T. Department
1 2 SJCE, Mysore, India Abstract— ECG (electrocardiogram) is very essential component for the doctors to diagnose the state of patient’s cardiovascular system. In critical situations doctors may need to examine ECG of patient instantly to take a firm and better decision in their absence near patient. In this paper a better way of instant ECG datatransfer, processing and display is demonstrated. Here ECG is acquired using simple 3 electrode single lead configuration then it is digitized and transmitted to Android smart phone in SMS message format. This SMS data is a bundle of values representing digital ECG. Acquired SMS data is fetched from inbox of the phone and processed for calculation of heart rate and detection of arrhythmia by Android application software. Then ECG is displayed on phone screen along with conclusion of heart rate and arrhythmia (if any). IndexTerms—ECG, Instant ECG,Android ECG, Cardiac monitoring
I. INTRODUCTION
Electrocardiogram is the waveform representing electrical activity of the heart. This is acquired by connecting skin impedance matching resistance electrodes to the surface arms and chest. A set of appropriate electrode connection made for acquiring single ECG waveform is called as lead. According biomedical standards totally there are twelve leads for complete analysis of activity of heart in various dimensions. Today in hospitals and diagnostic centers twelve lead ECG monitoring is being used worldwide. Even for treadmill test and analysis of patient they implement twelve lead ECG systems. So it is very comfortable to have ECG analysis at hospitals and diagnostic centers. Meanwhile if patient has to be monitored instantly and both patient and doctor are at different places or patient is in critical state away from hospital then there are different wireless ECG monitoring systems which communicate between patient and doctor to provide a better environment for ECG analysis. But the conventional wireless ECG monitoring systems dependent on short range networks such as Wimax, Wi-fi and Bluetooth networks.These systems need either desktop/laptop computers or dedicated hardware display systems. These conventional wireless systems also suffer from noise interference problems.
To overcome these hurdles of wireless ECG data transmission there is a need of long range, internet independent and noiseless network. The present GSM and CDMA networks are long range networks which cover most part of urban world with a strong resistance to noise interference. This paper elaborates a noise free wireless ECG transmission system and sophisticated display software. Instant ECG monitoring system has two parts; patient side hardware and doctor side software.Instant ECG monitoring system uses any one lead out of three AVR, AVL and AVF lead systemsto acquire ECG. The acquired ECG is digitized using an appropriate analog to digital converter. ADC output is a stream of digital values. These values are packed into a data bundle and then sent to a phone specific number by an advanced microcontroller through interfaced GSM system in the form of SMS. The phone which receives this SMS has Android operating system and has ECG reading application software. This ECG app fetches messages of only the particular number which was used to send the ECG data, from the SMS inbox and then displays the data in the form of a graph, which is the acquired ECG signal at patient side. As SMS platform is used to transmit the data there is very less possibility of noise interference. The ECG app software fetches the data from messages, processes it then displays the outcome in a more appropriate graphical way. The memory requirement is also less as standard single SMS can provide 140 bytes of data carriage. So in all the way the instant ECG monitoring system proves to be an efficient real time tool for on time cardiac monitoring.
II. SYSTEM ARCHITECTURE
As explained before Instant ECG monitoring system has two subsystems; a) data acquisition and transmission system, b) data process and display system. Data acquisition and transmission system is carried by the patient where data processing and display is done by the smart phone of the doctor with the help of dedicated Android app software. The architectures of both the systems are elaborated in this section.
Data acquisition is the process of sensing electric potential from the surface of the skin using electrodes and processing that electric voltage for analyzing the function of heart as ECG. The electrodes are placed at appropriate points on chest surface

2. International Journal For Research & Development in Technology
Paper Title:- Instant Elelectrocardiogram Monitoring in Android ISSN(O):- 2349-3585
Smart Phones (Vol.2, Issue-1)
28
Copyright 2014- IJRDT www.ijrdt.org
as directed by standards of ECG electrode placement. In this system we use three electrode single lead set up for acquiring ECG signal. So the system can monitor one of twelve standard ECG leads and hence only one waveform will be available for display. The voltage potential available at ECG cable output is amplified then band pass filtered. The filtered output is sampled and digitized. The digital values are stored into microcontroller memory. The microcontroller is the brain of this system. This acquires digital values from ADC output then sends them to GSM modem device. GSM modem is the bridge between mobile phone network and ECG acquisition system. Through this GSM modem with a SIM card of particular network provider with a distinct number microcontroller sends SMS to the data processing and display system present at doctors side. As explained before this data processing and display unit is doctors’ Android smart phone.
Figure 1. Patient side ECG acquisition and transmission The doctors’ smart phone to which ECG digital data has been sent is facilitated with updated Android smart phone operating system. The ECG Android application being installed in the smart phone fetches the SMS of the specific prescribed number from inbox then produces the digital values of ECG signal present in the SMS to plot waveform. Along with plotting of ECG waveform the application software also computes the heart rate using QRS detection algorithm and thus concludes the possible arrhythmia being occurred in heart rhythm. The type of arrhythmia detected by ECG application software is displayed along with the graph. If there’s no arrhythmia detected then ECG will be concluded normal by the software. The memory required by software is too less and cache will be cleared immediately once we stop the running application software. So there is advantage of low memory consumption by the application software. The application software utilizes QRS detection algorithm to detect heart rate and thus identifies arrhythmia inherited with acquired ECG. The functioning of application software can be modeled as given in below figure.
Figure 2. Functional diagram of ECG Application software in Android OS The ECG data available in the messages of specific number at the message Inbox are transferred to QRS detector algorithm and then for plotting the graph. Meanwhile results of QRS detection are sent for detection of arrhythmia. Arrhythmia detector analyses the presented results from the QRS detector with standard ECG data, then sends results for display indicating ECG embedded with any arrhythmia or normal. ECG displayed is static plot because this helps doctor to examine the waveform easy. Even if software fails to detect a distinct arrhythmia then doctor can identify the abnormality in the ECG waveform, this adds a flexible advantage of manual arrhythmia detection in this system.
III. RESULTS
As the ECG data is transmitted through most reliable mobile phone network there is very less possibilities of noise interference. This is internet free data transmission so no worries of data traffic. When ECG is normal display will be as given shown in below figure.
Figure 3. Android display showing acquired normal ECG It displays heart rate; that is beats per minute and the ECG type, which is normal as per instant acquisition. Further if acquired ECG is abnormal then application software analyzes the abnormality and displays the detected arrhythmia type, as given in below figure.
ADC
Microcontroller
GSM Modem
ECG Lead
Op Amp
BPF
SMS
Inbox
QRS
Detector
Display
Arrhythmia
Detector

3. International Journal For Research & Development in Technology
Paper Title:- Instant Elelectrocardiogram Monitoring in Android ISSN(O):- 2349-3585
Smart Phones (Vol.2, Issue-1)
29
Copyright 2014- IJRDT www.ijrdt.org
Figure 4. Android display of ECG manipulated with Tachycardia The detected heart rate simplifies detection of arrhythmia. Similarly Bradycardia, Pre ventricular contraction and Bundle branch blockage arrhythmias can be detected by this application software. The propagation delay of display of waveform depends upon number of ECG messages present in the SMS Inbox of smartphone. Propagation delay is directly proportional to the number of ECG messages present in SMS Inbox. So it is better to delete old ECG messages to have faster display of ECG. Along with that resolution of ECG waveform also increases with decrease in number of ECG messages or data. So memory management is also in users hand. If physician needs to see better display of ECG then he has to delete unwanted old ECG messages from the Inbox. This is an advantage for the user and the patient. This system provides a flexible memory management utility to operators.
IV.CONCLUSION
Instant ECG monitoring System is a faster, flexible, user friendly and Internet independent health service for cardiac patients and doctors. The system uses high security cell phone network for its communication between two ends. And as this is one side transmission system it is a simplex device which makes it simple, fast and cost effective. Its high security data transmission quality makes it a most reliable compared to other present wireless ECG monitoring systems.
As this system does not need Internet service for its operation it can work without any system crashes or hangouts. This trait adds one more crown of dependability on this system.
Memory consumption of ECG messages is very low compared to large data blocks used in conventional wireless ECG monitoring systems. The memory can be easily managed by end user by deleting unwanted ECG messages in the SMS Inbox. This does not affect other messages in the SMS inbox. This is the reason that system is user friendly. It also has some limitations, such as the display is quite small, but any way it depends on affordability of end user. It can detect only few types of arrhythmias mean while the doctor has to analyze the signal and conclude the arrhythmia in most of critical situations. Display is not real time dynamic; that is user has to run the application over and over to get very last ECG. This limitation can be overcome in the future where application software will be developed further.
V. FUTURE ENHANCEMENTS
The Instant ECG monitoring system can be further developed as compatible software application for different Smart phone software environments. Dynamic ECG display will ensure more real time cardiac monitoring. Hardware can be made simple if voice band is used for ECG signal transmission. Development of arrhythmia detection algorithm will enhance the reliability of the system to a new extent. This system can revolutionize wireless biomedical signal monitoring and analysis.
REFERENCES
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