Abstract

CANO, ME et al. A simple alternative for modulating and recording the PQRST complex. Rev. mex. ing. bioméd [online]. 2011, vol.32, n.2, pp.100-108. ISSN 2395-9126.

This work presents the instrumentation steps towards the development of a low cost personal device for conditioning, modulating in amplitude and recording the electrical activity generated by bipolar leads of the heart. Also, a method of remote monitoring using an audio transmitter-receiver in modulated frequency adapted to a PC sound card is considered. To determine the modulation effects on the PQRST complex, simultaneous measurements on several volunteers are carried out. The signal is measured twice, initially before the first modulation and again after the final demodulation. For comparison, the same signals are simultaneously passed through a commercial electrocardiograph. Because of the modulation effect, measurements between both methods show differences up to 13% in some intervals of the PQRST complex. The PR segment and the QRS wave are the most affected. In general, there is a good agreement between the recordings obtained with our device and the trademark electrocardiograph.

Keywords : Wireless; cardiac; audio; modulation.