Contactless recording of cardiac related thoracic conductivity changes

Author

Guardo, R. ; Trudelle, S. ; Adler, A. ; Boulay, C. ; Savard, P.

Author_Institution

Dept. de Genie Biomed., Ecole Polytech. de Montreal, Que., Canada

Volume

2

fYear

1995

fDate

20-23 Sep 1995

Firstpage

1581

Abstract

Cardiac related changes in the electrical conductivity distribution of the thorax were recorded in real-time with an electromagnetic sensor consisting of a 3.5 cm radius coil, a 4 MHz oscillator and an active RF voltmeter. Operation of the sensor is based on measuring changes in the amplitude of a marginal RF oscillator, caused by eddy current losses in the heart region. Signals recorded from 6 normal subjects in multiple sessions (1 hour to 1 month) showed good repeatability. The average SNR for signals recorded with the coil placed over the sternum was 34 dB. A possible application of this type of sensor is for non-invasive continuous assessment of left ventricular ejection fraction

Keywords

bioelectric phenomena; biomedical measurement; cardiology; electric admittance measurement; 1 h to 1 month; 3.5 cm; 34 dB; 4 MHz; active RF voltmeter; cardiac related thoracic conductivity changes; contactless recording; eddy current losses; electromagnetic sensor; heart region; left ventricular ejection fraction; marginal RF oscillator; noninvasive continuous assessment; normal subjects; signal repeatability; thorax; Coils; Conductivity; Contacts; Current measurement; Electromagnetic measurements; Loss measurement; Oscillators; Radio frequency; Thorax; Voltmeters;

fLanguage

English

Publisher

ieee

Conference_Titel

Engineering in Medicine and Biology Society, 1995., IEEE 17th Annual Conference

Conference_Location

Montreal, Que.

Print_ISBN

0-7803-2475-7

Type

conf

DOI

10.1109/IEMBS.1995.579839

Filename

579839