Kaye G C, Butrous G S, Allen A, Meldrum S J, Male J C, Camm A J
Department of Cardiology, St. Bartholomew's Hospital, London, England.
Pacing Clin Electrophysiol. 1988 Jul;11(7):999-1008. doi: 10.1111/j.1540-8159.1988.tb03944.x.
The effects of injected 50 Hz alternating current on the function of cardiac pacemakers has been observed in 18 patients with implanted unipolar VVI units. Current, in the range 0-600 microA was applied via electrodes attached to the patients' upper body and feet and fed from a specially designed current injection unit at the bedside. Most implanted pacemakers reverted to interference mode in the current range 29-250 microA. At current levels just below the reversion current all units developed irregular and inappropriate pacing. This current level was pacemaker dependent and varied in the range 27-246 microA. The total reversion current depended on the location of the injecting electrodes and on the patients' posture. The sensitivity of the units to injected interference was increased by deep inspiration. Temporary pacing catheters fitted to an additional ten patients were used to monitor the interference voltage which would be sensed by an implanted unit. This voltage was similarly dependent on patient posture and on deep respiration. Current injection has proved to be a safe, controllable and reproducible method of testing the sensitivity of implanted pacemakers to 50 Hz external interference.
在18例植入单极VVI起搏器的患者中，观察了注入50Hz交流电对心脏起搏器功能的影响。通过连接在患者上身和脚部的电极施加0至600微安范围内的电流，电流由床边专门设计的电流注入装置提供。大多数植入的起搏器在29至250微安的电流范围内恢复为干扰模式。在略低于恢复电流的电流水平下，所有起搏器都出现了不规则和不适当的起搏。该电流水平取决于起搏器，范围在27至246微安之间。总恢复电流取决于注入电极的位置和患者的姿势。深吸气会增加起搏器对注入干扰的敏感性。另外10例患者使用的临时起搏导管用于监测植入装置会感知到的干扰电压。该电压同样取决于患者的姿势和深呼吸。事实证明，电流注入是一种安全、可控且可重复的方法，用于测试植入起搏器对50Hz外部干扰的敏感性。
