Martin G, Cosin J, Such M, Hernandez A, Llamas P
Eur Heart J. 1986 Jul;7(7):560-9. doi: 10.1093/oxfordjournals.eurheartj.a062106.
To relate the evolution of ventricular fibrillation (VF) to the haemodynamic recovery after cardioversion, we characterized the differences in the ECG power spectrum (PS) time course, among different types of VF: under control conditions, with previous administration of nifedipine and on cardiopulmonary bypass (CPB). In the first few seconds VF showed a PS with a narrow peak between 8 and 15 Hz and its higher harmonics, suggesting some organization and regularity. In the following 40 seconds, the arrhythmia accelerated slightly, maintaining an organized spectrum. Afterwards, the PS became slow and irregular, losing its initial characteristics after 60 seconds. Conversely, VF on CPB maintained its organized PS, over a prolonged period. Previous administration of 0.32, 0.64 mg kg-1 of nifedipine maintained the initial characteristics of the PS for 90 and 150 seconds. Similar results were obtained with previous autonomic blockade. In another group of dogs, defibrillation was performed after successive periods of VF, to study electromechanical dissociation (EMD). In all control dogs, EMD was observed after 90 seconds of VF. Pretreatment with nifedipine postponed EMD until 120-150 seconds and was not observed in dogs on CPB. The PS time course during VF seems a reliable method of analyzing and quantifying the different types of VF. It could be related with the onset of EMD, reflecting the metabolic alterations that happen during VF. Nifedipine could delay the ischaemic effects during VF and increase the possibility of successful cardiac resuscitation.
为了将心室颤动（VF）的演变与复律后的血流动力学恢复相关联，我们对不同类型的VF在心电图功率谱（PS）时间进程上的差异进行了表征：在对照条件下、先前给予硝苯地平后以及在体外循环（CPB）期间。在最初的几秒钟内，VF的PS在8至15Hz之间有一个窄峰及其高次谐波，表明存在一定的组织性和规律性。在接下来的40秒内，心律失常略有加速，维持着有组织的频谱。之后，PS变得缓慢且不规则，60秒后失去其初始特征。相反，CPB期间的VF在较长时间内维持其有组织的PS。先前给予0.32、0.64mg/kg的硝苯地平可使PS的初始特征分别维持90秒和150秒。自主神经阻滞预处理也获得了类似结果。在另一组犬中，在连续的VF期后进行除颤，以研究电机械分离（EMD）。在所有对照犬中，VF 90秒后观察到EMD。硝苯地平预处理将EMD推迟至120 - 150秒，而CPB犬未观察到EMD。VF期间的PS时间进程似乎是分析和量化不同类型VF的可靠方法。它可能与EMD的发生有关，反映了VF期间发生的代谢改变。硝苯地平可延迟VF期间的缺血效应并增加心脏复苏成功的可能性。
