High Resolution
Electrocardiography in Healthy Dogs: Time Domain Parameters and
Comparison of the Non-Stationary (Wigner Distribution) Versus
Standard Stationary Frequency Domain Analysis Methods
M. BERNADIČ, P. HUBKA, P. SLAVKOVSKÝ, H.
PETRÁŠOVÁ, J. HOLZEROVÁ, D. MAASOVÁ, L. ZLATOŠ, B.
MLADOSIEVIČOVÁ, I. HULÍN
Institute of Pathophysiology, Medical School, Comenius
University, Bratislava, Slovak Republic
Received April 2, 2004
Accepted November 26, 2004
On-line available January 10, 2005
Summary
Fractionated heart activation can be detected as late potentials
from surface recordings of signal-averaged electrocardiograms
(SA ECG) which are considered as a marker of sustained
ventricular tachycardia. For animal studies, reference values in
time and frequency domain analyses are essentially missing. In
the present study, we have established reference values in SA
ECG time domain analysis and time-frequency representation of
heart activation in healthy dogs. A group of 25 healthy mongrel
dogs (body weight 12-15 kg) was investigated. Wigner
distribution and our modification of Fast Fourier transform
(FFT), gliding window FFT, was applied in SA ECG frequency
domain analysis. Reference values in time domain SA ECG were
established. Time and voltage criteria were adapted to short
duration of heart cycle and fast voltage decrement of the QRS
complex in dogs. Wigner distribution and gliding window FFT were
applied in order to describe mean heart activation in the
frequency domain. Contribution of higher frequencies (30-80 Hz)
was detected by both frequency analysis methods in the second
third of ventricular activation in healthy animals. Presented
results could offer a basis for further experimental
arrhythmologic studies.
Key words
Signal-averaged ECG • Spectral analysis • Reference values •
Late potentials
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