title: A comparison between the automatized impedance cardiography and pulsed-wave Doppler echocardiography methods for measurements of stroke volume (SV) and systolic time intervals (STI).
abstract: Stroke volume (SV) and systolic time intervals (STI) were measured automatically using impedance cardiography signals (ICG) and compared with those obtained by pulsed-wave Doppler echocardiography using the apex approach. The comparison was made in 9 healthy male subjects, mean age 24.9 +/- 12.2 years, using recordings of 10 heart cycles simultaneously obtained by the two methods. During measurements the subjects rested in the supine position. There were no differences between mean values of SV determined by the two methods as well as between mean values of ejection time (ET) (p > 0.8 and p > 0.9, respectively). The pre-ejection period (PEP) estimated by ICG was 22 ms longer than that determined by echocardiography (p < 0.001). The relationship between SV values measured by impedance cardiography (SVA) vs those calculated by echocardiography (SVE) was found to be close to the line of identity in the range of measurements. The regression equation for SV was: SVA = 0.784.SVE + 15 (r = 0.69, p < 0.001, SEE = 10.7 ml). We conclude that automatic determination of SV and ET from ICG signals provides results comparable in absolute values with those obtained by the pulsed wave Doppler ultrasonocardiography using the apex approach for subjects remaining in the supine position.
authors.affiliation: Department of Applied Physiology, Polish Academy of Sciences, Warsaw.
authors.forename: G
authors.initials: G
authors.lastname: Cybulski
authors.forename: Z
authors.initials: Z
authors.lastname: Miśkiewicz
authors.forename: J
authors.initials: J
authors.lastname: Szulc
authors.forename: A
authors.initials: A
authors.lastname: Torbicki
authors.forename: T
authors.initials: T
authors.lastname: Pasierski
mesh_terms: D000328:Adult; D002307:Cardiography, Impedance; D015150:Echocardiography, Doppler; D006801:Humans; D008297:Male; D013318:Stroke Volume / Q000502:physiology; D013599:Systole / Q000502:physiology