Post-shock synchronized pacing in isolated rabbit left ventricle: evaluation of a novel defibrillation strategy.
Post-shock synchronized pacing in isolated rabbit left ventricle: evaluation of a novel defibrillation strategy.
复制标题
离体兔左心室电击后同步起搏：新型除颤策略的评估。
DOI：
10.1111/j.1540-8167.2007.00792.x
复制
发表时间：
2007
影响因子：
2.7
通讯作者：
Lin,Shien-Fong
中科院分区：
文献类型：
--
作者：
Tang,Liang;Hwang,Gyo-Seung;Song,Juan;Chen,Peng-Sheng;Lin,Shien-Fong
简介：近阈值除颤电击失败后，出现等电窗（IEW）和快速重复反应，重新引发室颤（VF）。我们假设，适当的定时（同步）postshock起搏刺激（SyncP）可能会捕获的重复响应过程中恢复的组织，并防止电击后重新启动VF，从而提高除颤efficacy.Methods和Results：我们探讨了影响postshock SyncP在离体兔心脏（n = 12）的除颤疗效。IEW后，对左心室（LV）前/后段的恢复组织进行光学记录引导的真实的实时检测和电刺激（5 mA）。IEW持续时间为69 ± 13 ms。在相同的电击强度下，成功和失败的除颤事件分别与SyncP捕获的50%和15%的心肌相关（P < 0.001）。与前左心室刺激（55%; P < 0.01）相比，后左心室电刺激导致75%的夺获心肌事件，并导致更高的成功除颤率（14%，后左心室vs. 3%，前左心室）。电击后SyncP终止VF的总体成功率约为10%。电击后SyncP心肌夺获失败的原因包括低强度电击后IEW缺失（42.9%）、参考部位位置不正确（25.7%）、起搏电极位置不正确（17.9%）以及其他原因（如波突破）（13.5%）。休克后SyncP输注到左心室后部比输注到左心室前部更有效终止室颤。
Introduction:A failed near‐threshold defibrillation shock is followed by an isoelectric window (IEW) and rapid repetitive responses that reinitiate ventricular fibrillation (VF). We hypothesized that properly timed (synchronized) postshock pacing stimuli (SyncP) may capture the recovered tissues during the repetitive responses and prevent postshock reinitiation of VF, resulting in improved defibrillation efficacy.Methods and Results:We explored the effect of postshock SyncP on defibrillation efficacy in isolated rabbit hearts (n = 12). Optical recording‐guided real‐time detection and electrical stimulation (5 mA) of recovered tissues in anterior/posterior left ventricle (LV) were performed following IEW. The IEW duration was found to be 69 ± 13 ms. With the same shock strength, successful and failed defibrillation episodes were associated with 50% and 15% of the myocardium, respectively, captured by the SyncP (P < 0.001). Electrical stimulation from the posterior LV resulted in 75% of episodes capturing myocardium, as compared with anterior LV stimulation (55%; P < 0.01) and higher successful defibrillation rate (14%, posterior vs. 3%, anterior LV). The overall success in terminating VF by postshock SyncP was approximately 10%. The causes for failed myocardium capture by postshock SyncP included lack of IEW after low‐strength shock (42.9%), incorrect locations of reference site (25.7%) and pacing electrodes (17.9%), and others, such as wave breakthroughs (13.5%).Conclusion:Postshock SyncP was feasible and the larger the myocardium captured area, the more likely was the successful defibrillation. Postshock SyncP delivered to the posterior LV was more effective than anterior LV to terminate VF.