Jenkins J M, Dick M, Collins S, O'Neill W, Campbell R M, Wilber D J
Pacing Clin Electrophysiol. 1985 Jul;8(4):512-27. doi: 10.1111/j.1540-8159.1985.tb05853.x.
The pill electrode, which was developed for esophageal electrocardiography, has found application in transesophageal atrial pacing during procedures such as conversion of tachycardia, electrophysiologic measurement, and acceleration of heart rate to produce stress during cardiac imaging studies. This paper presents theoretical studies that examine the relationship of interelectrode distance, current level, and pulse duration to the achievement of successful capture. Theoretical results agree with our clinical findings, i.e., current levels of 25 mA are effective to sustain capture; increased pulse duration reduces current requirements; and close bipolar spacing combines efficacy with safety. Results of animal studies performed to assess the extent of esophageal burn injury reveal that current levels in excess of 75 mA are required to produce lesions in short-term (under 30 minutes) pacing, and greater than 60 mA in long-term (4 hours) pacing. These results are based on experiments using a pulse duration of 2 ms, and the current levels that produce injury will be considerably lower if longer pulse durations are used. Typical current levels and pulse durations for successful capture are presented for 46 subjects in several new clinical applications. Termination of tachycardia, basic electrophysiologic measurements, and controlled acceleration of heart rate can be performed noninvasively with this technique.
为食管心电图开发的药丸电极已应用于诸如心动过速转复、电生理测量以及在心脏成像研究中加速心率以产生应激等手术过程中的经食管心房起搏。本文介绍了理论研究，探讨了电极间距、电流水平和脉冲持续时间与成功夺获之间的关系。理论结果与我们的临床发现一致，即25 mA的电流水平对于维持夺获有效；增加脉冲持续时间可降低电流需求；紧密的双极间距将有效性与安全性结合起来。为评估食管烧伤损伤程度而进行的动物研究结果表明，短期（30分钟以内）起搏产生损伤需要超过75 mA的电流水平，长期（4小时）起搏则需要超过60 mA。这些结果基于使用2 ms脉冲持续时间的实验，如果使用更长的脉冲持续时间，产生损伤的电流水平将显著降低。在几个新的临床应用中，给出了46名受试者成功夺获的典型电流水平和脉冲持续时间。使用该技术可以无创地进行心动过速的终止、基本电生理测量以及心率的控制性加速。
