Thakur R K, Souza J J, Chapman P D, Troup P J, Wetherbee J N
Division of Cardiology, Medical College of Wisconsin, Milwaukee.
Pacing Clin Electrophysiol. 1994 May;17(5 Pt 1):919-23. doi: 10.1111/j.1540-8159.1994.tb01433.x.
Experimental and clinical data using epicardial patch electrodes and monophasic waveform suggest that electrode polarity may be an important determinant of defibrillation efficacy. Our objective was to examine the effect of electrode polarity in an animal model using a nonthoracotomy system and monophasic and biphasic waveforms for defibrillation. We examined the effect of lead polarity in 14 pentobarbital anesthetized dogs (21.1 +/- 2.4 kg) using monophasic and biphasic shocks and a nonthoracotomy system. Monophasic and single capacitor biphasic shocks of 10-msec total duration were used. The lead system consisted of a right ventricular catheter electrode with 4-cm2 surface area and a left chest wall subcutaneous patch electrode with 13.9-cm2 surface area. Electrode polarities RV(-)-Patch(+) and RV(+)Patch(-) were tested using both monophasic and biphasic waveforms. Alternating current was used to induce ventricular fibrillation and test shocks were delivered after 10 seconds of ventricular fibrillation. Each polarity configuration for monophasic and biphasic waveforms was tested four times at five different capacitor voltage levels (200-600 V, in 100-V increments). Defibrillation efficacy curves were constructed using logistic regression analysis for each animal and energies associated with 80% probability of successful defibrillation (E80) were determined. The mean E80 +/- SD values were as follows. Monophasic waveform: RV(-)Patch(+) 23.4 +/- 7.5 J; RV(+)Patch(-) 20.9 +/- 7.9 J (P < 0.03). Biphasic waveform: RV(-)Patch(+) 15.8 +/- 6.8 J; RV(+)Patch(-) 12.5 +/- 6.0 J (P < 0.03). The mean impedance values for both waveforms using either polarity ranged from 65.4 to 67 ohms and were not significantly different.(ABSTRACT TRUNCATED AT 250 WORDS)
使用心外膜贴片电极和单相波形的实验及临床数据表明，电极极性可能是除颤效果的一个重要决定因素。我们的目的是在动物模型中，使用非开胸系统以及单相和双相波形进行除颤，来研究电极极性的影响。我们在14只戊巴比妥麻醉的犬（体重21.1±2.4千克）身上，使用单相和双相电击以及非开胸系统，研究导联极性的影响。使用了总持续时间为10毫秒的单相和单电容双相电击。导联系统由一个表面积为4平方厘米的右心室导管电极和一个表面积为13.9平方厘米的左胸壁皮下贴片电极组成。使用单相和双相波形测试了电极极性RV(-)-Patch(+)和RV(+)Patch(-)。使用交流电诱发心室颤动，并在心室颤动10秒后给予测试电击。在五个不同的电容电压水平（200 - 600伏，以100伏递增）下，对单相和双相波形的每种极性配置进行了四次测试。使用逻辑回归分析为每只动物构建除颤效果曲线，并确定与80%成功除颤概率相关的能量（E80）。平均E80±标准差数值如下。单相波形：RV(-)Patch(+)为23.4±7.5焦耳；RV(+)Patch(-)为20.9±7.9焦耳（P<0.03）。双相波形：RV(-)Patch(+)为15.8±6.8焦耳；RV(+)Patch(-)为12.5±6.0焦耳（P<0.03）。两种波形使用任一极性时的平均阻抗值在65.4至67欧姆之间，且无显著差异。（摘要截选至250字）
