心室颤动的时-频分析和胺碘酮的作用

研究心室颤动时主导频率的动态性空间时间变化。在19只犬中建立正交心电图和心脏电除颤系统;诱发心室颤动持续10~30 s;使用时-频分析法分析心室颤动时频率的时频变化。另有4只犬在诱发心室颤动后静注胺碘酮100 mg以观察主导频率的改变。结果显示:在427个10 s VF和335个30 s VF的试验中,主导频率的变化与平均频率相差12%~18%;79个使用胺碘酮的试验中,主导频率的均值和变异性均降低。表明:在10~30 s心室颤动时心电图主导频率有明显和持续性的变异,胺碘酮可减小心室颤动时的频率和变异。

Time-frequency Analysis of Ventricular Fibrillation And the Effects of Amiodarone

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.