• Compact multichannel ECG system for noninvasive location of myocardial ischemia
• The model measurements of the liver iron stores

Result 1: Compact multichannel ECG system for noninvasive location of myocardial ischemia

Projects: APVV-51-059005 a VEGA 2/7084/27

Authors: V. Rosík, S. Karas, E. Hebláková, M. Tyšler

Compact portable system for body surface potential mapping was developed that enables early noninvasive detection of possible myocardial ischemia. The measuring system with intelligent data acquisition unit enables simultaneous measurement of up to 144 ECG leads. Active electrodes, powering by a Li-ion cell and optical link to the USB port of the controlling notebook reduce the noise in ECG and guarantee the patient safety. Modular software controls the measurement process, ECG monitoring and recording and mapping of the dynamics of the ECG potentials on the chest. It ca be used for more detailed cardiac diagnostics. The method for detection of possible ischemia is based on an inverse solution looking for a dipolar source that best represents the changes in surface maps of the time integrals of ECG potentials measured in situation with manifestation of ischemia, e.g. after the health condition has changed or after excercise. On a group of patients after cardiac intervention the ability of the method to identify the reperfused myocardial area was demontrated, on another group of ischemic patients the possibility to detect an ischemic lesion was tested. Two systems for the Slovak Healthcare University and Faculty of Biomedical Engineering CTU in Kladno were realized.

Publications:

• TYŠLER M., KNEPPO P., ROSIK V., KARAS S., HEBLÁKOVÁ E. and MUZIK J.: Body Surface Potential Mapping for Noninvasive Ischemia Detection. IFMBE Proceedings, vol.20 (NBC - 14th Nordic Baltic Conference on Biomedical Engineering and Medical Physics), 339-342, ISSN 1680-0737, ISBN 978-3-540-69366-6 [CD-ROM].

• KARAS S., HEBLÁKOVÁ E., ROSÍK V., TYŠLER M.: Multichannel high-resolution electrocardiograph developed in Matlab. In: Technical Computing Prague 2008. Sborník příspěvků 16. ročníku konference. 16th Annual Conference Proceedings. Humusoft, s.r.o., Praha 2008, 55. ISBN 978-80-7080-692-0.

Result 2: The model measurements of the liver iron stores

Project: APVV-51-059005 a VEGA 2/7084/27

Authors: V. Zrubec, J. Maňka, I. Šimáček, M. Škrátek, P. Jurdák

 A method and a model of equipment for noninvasive measurement of the iron load in the liver, which will (in some cases) replace the invasive and risk needle biopsy, have been designed. For the calibration and evaluating of data acquired by this SQUID biosusceptometer two testing systems have been designed: 1) Electronic phantom for measurement of the volume magnetic susceptibility enabling to determine the ferritin content in the liver from biosusceptometer measured data. 2) Complex model of chest and abdomen for the calibration of the biosusceptometer, enabling to measure the Fe concentrations in different-sized liver models and simultaneously to observe the air influence in the lungs. Using these models it is also possible to determine the influence of liver position change on measurement uncertainty. To simulate the magnetic properties of ferritin, the FeCl₃ solution in distilled water has been used. The content of FeCl₃ corresponded to the concentrations of Fe of 30 mg to 3g per liter of water, which are approximately the concentrations of Fe per one kg of the liver tissue.

Publications:

• ZRUBEC, Vladimír - MAŇKA, Ján - ŠKRÁTEK, Martin. Adjustable electronic phantom for volume magnetic susceptibility measurements. In Journal of Physics: Conference Series. ISSN 1742-6588, 2008, vol. 97, art. no. 012126. (Scopus)
• JURDÁK, Peter - KOPÁNI, Martin - ŠIMÁČEK, Ivan - MAŇKA, Ján - ŠKRÁTEK, Martin: Magnetometric Measurements of Ferro- or Ferrimagnetic Microparticles Dispersed in Medium Approximating the Intracellular Environment. In Jian-Ping Wang Nanoscale Magnetic Materials and Applications, Mater. Res. Soc. Symp. Proc. Volume 1032E, Warrendale, PA, 2008, 1032-I04-19.