Ventricular fibrillation (VF) is a poorly understood yet potentially lethal cardiac arrhythmia. The electrocardiogram (ECG) time series of VF is investigated by comparison of the linear and non-linear features of VF time series and surrogates in which internal correlations have been destroyed.
From 40 ECG time series of human VF and 40 surrogate time series, three quantities are evaluated: the percentage of the linear time-frequency distribution (TFD) exceeding a threshold the non-linear coarse-grained correlation dimension (Dcg), and the percentage of diagonal lines in the non- linear recurrence plot longer than 10 elements (D10).
It is found that the mean (SD) percent threshold TFD and Dcg are higher for the surrogates (6.7% (1.3) and 5.3 (0.6)) than the VF time series (5.6% (0.7) and 3.8(O.9)), whereas the mean D10 is higher for the VF time series (49% (13)) than the surrogates (32% (7)). All of these differences are significant (p< 0.0001) and indicate greater order in the VF time series than in the surrogates. It is therefore shown that both linear and non-linear signal analysis demonstrate order in the ECG time series of VF.
Clayton RH, Murray A. Linear and non-linear analysis of the surface electrocardiogram during human ventricular fibrillation shows evidence of order in the underlying mechanism. Med. Biol. Eng. Comput., 1999, 37, 354-358.
Professor Alan Murray, Freeman Unit, Newcastle upon Tyne. Tel: +44 (0)191-223-1370.
Regional Medical Physics Department, Newcastle General Hospital, Newcastle upon Tyne, NE4 6BE, UK.
Tel: +44 (0)191-233-6161 Fax: +44 (0)191-226-0970 E-mail: webmaster@rmpd.org.uk Web: http://www.rmpd.org.uk
By using this site you agree to our Terms and Conditions of Use. Please read our legal page.
Regional Medical Physics Department, a Clinical Directorate of the Newcastle upon Tyne Hospitals NHS Foundation Trust.
Copyright ©1999-2008 All Rights Reserved. Revised 28 April, 2008.
