Viktoriya Kabashnyuk
Faculty: Computer information technologies and automatic
Cathedra: Electronic technique
Speciality: Scientific analytical and ecological devices and systems
Supervisor of studies: Dmitry Kuznetsov
Review on the theme of master's work: "Foundation of methods and development of resources of ECG monitoring of human"
The object of research
The object of my master's work - is a portable 12-channel electrocardiograph.
Goals and objectives
It is the development of portable, inexpensive 12-channel ECG on modern element base with simultaneous removal of 12 standard leads.
Requirements
ECG input circuit should amplify a weak signal in the voltage range 0,5-5 mV in conjunction with the constant component of up to +- 300mV and the synphase component of up to 1 V. The frequency band is from 0.05 to 100 Hz [1].
Introduction
In our time disease of the heart are widespread. And increasingly, such diseases and variations affect the young people. It is therefore very important to advance to capture and recognize them. Cardiography is dealing with these questions.
In Ukraine for the past 25 years the prevalence of cardiovascular disease among the population increased by 3 times, and the mortality rate from them - at 45%.
Between standard, enhanced, and chest leads, there are relationships that need to be considered in the development of cardio equipment:
Figure 1 - Einthoven leads
where L, R, F-are the potentials of the left, right hand and left foot respectively.
Figure 2 - Reinforced Goldberger leads
Figure 3 - chest Wilson - Goldberger leads
where Ci-is the point on the surface of the chest, i = 1 .. 6 [2].
Placement of electrodes for removing 12 standard leads is shown in Figure 4.
Figure 4 - Placement of electrodes on the human body
Animation consists of 10 frames, the volume of the animation - 122 KB; size - 500x280 pixels
Designing the structure of the input circuits 12-channel ECG
The most complete information about the patient's condition can be obtained only if the parallel withdrawal of all 12 leads.
Go to the sigma-delta ADC
Figure 5 shows a typical structure of a single-channel ECG.
Figure 5 - Typical structure of single-channel ECG with a low-resolution ADC
Using of modern high-performance multi-channel delta-sigma ADC, high-resolution fast channel switching can significantly simplify the circuitry of channels of ECG [3]. The resulting structure is shown in Figure 6.
Figure 6 - Structure of the measuring channel ECG with a delta-sigma ADC
Structure of the input circuits 12-lead ECG was obtained with the light of the above (Figure 7).
Figure 7 - The proposed structure of the input circuits 12-channel ECG
Conclusions
The proposed structure of the input circuits 12-lead ECG by using a sigma-delta ADC is characterized by a high-resolution fairly simple circuitry. In addition, the simultaneous removal of all 12 standard leads, which is the key to obtaining the most complete picture of the patient's condition, allows [4, p.255].
References
1. Instruments for measuring bioelectric potentials of the heart. General technical requirements and test methods. GOST 19687 - 89 - M.: Publishing House of Standards, 1989 - 19 s.
2. Technology EKG/ By red. A. Arakcheeva, O. Sivachova. - 2011 [Electronic resource] URL: http://usefulnurse.ucoz.ru/publ/19-1-0-123 (date accessed 04/25/2011).
3. T.Miani, A.Vlasenko Sigma-delta ADC AD7739, AD7734, AD7738, AD7739 in systems with low power [Electronic resource] URL: http://www.kit-e.ru/articles/dac/2006_9_54.php (date accessed 14/04/2011) .
4. V.Kabashnyuk, D.Kuznetsov, Justification structure of the input circuits 12-channel electrocardiograph, Automation of technological objects and processes. Search for young people. Collection of Scientific Papers XI Scientific-Technical Conference and postgraduate students in the city of Donetsk, May 17-20, 2011 - Donetsk, Donetsk National Technical University, 2011. - 306.
Note
By the time of writing of the abstract Graduate work is not completed yet. Final results were obtained in December 2011. You can take full text of the research from the author or supervisor after this date.