Defibrillation success with high frequency electric fields is related to degree and location of conduction block.
Defibrillation success with high frequency electric fields is related to degree and location of conduction block.
复制标题
高频电场除颤的成功与否与传导阻滞的程度和位置有关。
DOI：
10.1016/j.hrthm.2013.01.016
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发表时间：
2013
期刊：
影响因子：
5.5
通讯作者：
Tung,Leslie
中科院分区：
文献类型：
--
作者：
Weinberg,SethH;Chang,KellyC;Zhu,Renjun;Tandri,Harikrishna;Berger,RonaldD;Trayanova,NataliaA;Tung,Leslie
背景我们最近证明，高频交流电（HFAC）电场可以通过诱导振荡的、升高的跨膜电位（Vm）可逆地阻断心脏中的传播，该跨膜电位在电场持续时间内使心肌细胞保持在不应状态，并可以终止心律失常，包括室颤（VF）。注意事项量化和表征传导阻滞（CB）诱导HFAC领域，并确定CB的程度是否可以用来预测除颤successful. METHODS光学映射在成年豚鼠心脏（n = 14），和模拟进行了解剖学上准确的兔心室模型。对心室施加HFAC场（50-500 Hz）。一种新的功率谱度量CB-在1-30 Hz范围内的频谱功率损失，称为传导功率损失（LCP）-在HFAC场进行了评估，并与除颤成功和VF易损性进行了比较。在心外膜表面进行的光学标测实验表明，LCP和CB区域的大小与VF开始和终止显著相关。在模拟中，亚表面心肌LCP和CB大小与VF终止比表面值更密切相关。模拟结果的多元线性回归分析表明，虽然CB的表面和表面下的心肌是预测，表面下的心肌CB是更好的预测除颤successful.CONCLUSIONSHFAC领域引起的CB场依赖性状态，和除颤成功的程度和位置的CB。
BACKGROUNDWe recently demonstrated that high frequency alternating current (HFAC) electric fields can reversibly block propagation in the heart by inducing an oscillating, elevated transmembrane potential (Vm) that maintains myocytes in a refractory state for the field duration and can terminate arrhythmias, including ventricular fibrillation (VF).OBJECTIVESTo quantify and characterize conduction block (CB) induced by HFAC fields and to determine whether the degree of CB can be used to predict defibrillation success.METHODSOptical mapping was performed in adult guinea pig hearts (n = 14), and simulations were performed in an anatomically accurate rabbit ventricular model. HFAC fields (50–500 Hz) were applied to the ventricles. A novel power spectrum metric of CB—the loss of spectral power in the 1–30 Hz range, termed loss of conduction power (LCP)—was assessed during the HFAC field and compared with defibrillation success and VF vulnerability.RESULTSLCP increased with field strength and decreased with frequency. Optical mapping experiments conducted on the epicardial surface showed that LCP and the size of CB regions were significantly correlated with VF initiation and termination. In simulations, subsurface myocardial LCP and CB sizes were more closely correlated with VF termination than surface values. Multilinear regression analysis of simulation results revealed that while CB on both the surface and the subsurface myocardium was predictive, subsurface myocardial CB was the better predictor of defibrillation success.CONCLUSIONSHFAC fields induce a field-dependent state of CB, and defibrillation success is related to the degree and location of the CB.