title: [Time-frequency analysis of ventricular fibrillation and the effects of amiodarone].
abstract: This study is to quantify time-varying dominant frequencies in electrocardiogram (ECG) during the ventricular fibrillation (VF). Orthogonal ECG (sagittal, x; transverse, y; and longitudinal, z) and the transvenous two-leads defibrillation systems were set in 19 dogs. Time-frequency analysis was used to assess changes in the dominant frequency within ECG recorded in dogs during trials of 10-30 s of VF. In 4 additional dogs, the dominant frequencies were compared during 10 s of VF before and after administration of amiodarone. Results showed that in the 427 trials of 10 s VF and 335 trials of 30 s VF, average variation in the dominant frequency was considerable, between +/- 12%-18%. The frequencies orthogonal ECG during 10 s VF were distributed symmetrically above and below the mean frequency like a normal distribution. In the 79 trials with administration of amiodarone during 10 s VF in all three ECG, the mean frequencies decreased from 6.5 (x), 7.4 (y) and 7.0 Hz (z) to 6.1, 6.4 and 6.3 Hz (P < 0.01), respectively, and the variation in dominant frequencies decreased from 1.18, 1.38 and 1.19 to 0.98, 1.11 and 1.02 Hz (P < 0.05) respectively. The results confirmed that the frequencies of 10-30 s VF in ECG vary considerably and continuously, and amiodarone decreases this variation.
authors.affiliation: Key Lab for Biomechanics & Tissue Engineering of Ministry of Education, College of Bioengineering, Chongqing University, Chongqing 400044, China. kewang97@mail.diptt.ln.cn
authors.forename: Ke
authors.initials: K
authors.lastname: Wang
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Deng
authors.forename: Zaipin
authors.initials: Z
authors.lastname: Xu
authors.forename: Shugang
authors.initials: S
authors.lastname: Li
authors.forename: Yan
authors.initials: Y
authors.lastname: Liu
authors.forename: Ran
authors.initials: R
authors.lastname: Guo
authors.forename: Abhijit
authors.initials: A
authors.lastname: Patwardhan
authors.forename: Fabio
authors.initials: F
authors.lastname: Leonelli
mesh_terms: D000638:Amiodarone / Q000494:pharmacology*; D000818:Animals; D000889:Anti-Arrhythmia Agents / Q000494:pharmacology*; D004285:Dogs; D004554:Electric Countershock; D004562:Electrocardiography / Q000187:drug effects*; D005260:Female; D008297:Male; D014693:Ventricular Fibrillation / Q000503:physiopathology*
chemical_list: D000889:Anti-Arrhythmia Agents; D000638:Amiodarone