Jones D L, Klein G J
J Electrocardiol. 1984 Oct;17(4):393-9. doi: 10.1016/s0022-0736(84)80077-1.
Ventricular fibrillation (VF) has been classified electrocardiographically as "fine amplitude" or "coarse amplitude" VF. It has been suggested that coarse VF represents increased "synchronization" of myocardial activation which could result in lower thresholds for defibrillation. To test the "synchronization" differences between coarse VF and fine VF, we induced VF in ten normal anaesthetized dogs. Standard limb lead and His bundle electrograms were recorded simultaneously with 12 bipolar epicardial electrograms (eight dogs) and six lead ECG (two dogs). Activation "synchronization" was assessed by calculating the standard deviations (SD) of electrogram activation times during one coarse VF and one fine VF cycle. Less synchronization during VF was indicated by a 50% larger SD (CVF: 29.3 +/- 1.1 msec, FVF: 32.6 +/- 1.6 msec) compared to ventricular pacing (21.2 +/- 1.6 msec) and 500% larger than sinus rhythm (6.5 +/- 0.5 msec). Coarse VF and fine VF did not differ. In addition, the 6-lead ECG recorded during early VF had episodes of coarse VF and fine VF occurring simultaneously. The amplitude of all electrograms diminished over 15 minutes until only fine VF could be recorded. We conclude that coarse VF does not reflect greater synchronization of activity than fine VF early in fibrillation (five minutes). Rather, differences are due to lead orientation. Later in the fibrillation bout, fine VF probably reflects metabolically induced degeneration of cellular excitability.
室颤（VF）在心电图上已被分类为“细颤”或“粗颤”。有人提出，粗颤代表心肌激活的“同步性”增加，这可能导致除颤阈值降低。为了测试粗颤和细颤之间的“同步性”差异，我们在十只正常麻醉的狗身上诱发了室颤。同时记录标准肢体导联和希氏束电图以及12个双极心外膜电图（8只狗）和六导联心电图（2只狗）。通过计算一个粗颤周期和一个细颤周期内心电图激活时间的标准差（SD）来评估激活“同步性”。与心室起搏（21.2±1.6毫秒）相比，室颤期间同步性降低表现为标准差增大50%（粗颤：29.3±1.1毫秒，细颤：32.6±1.6毫秒），且比窦性心律（6.5±0.5毫秒）大500%。粗颤和细颤没有差异。此外，在室颤早期记录的六导联心电图有粗颤和细颤同时出现的情况。所有心电图的振幅在15分钟内逐渐减小，直到只能记录到细颤。我们得出结论，在颤动早期（五分钟），粗颤并不比细颤反映出更大的活动同步性。相反，差异是由于导联方向。在颤动发作后期，细颤可能反映了代谢诱导的细胞兴奋性退化。
