Kudenchuk P J, Bardy G H, Dolack G L, Poole J E, Mehra R, Johnson G
Department of Medicine, University of Washington, Seattle 98195.
Circulation. 1994 Jun;89(6):2641-4. doi: 10.1161/01.cir.89.6.2641.
Recent development of a prototype single-lead unipolar transvenous defibrillator offers the possibility of device implantation with the ease of a permanent pacemaker. Lowering defibrillation energy requirements would allow for a further reduction in defibrillator generator size and enhance the feasibility of pacemaker-like placement. However, if achieving a lower defibrillation energy requires placing additional intracardiac leads, the potential advantage of a smaller generator may be offset by the disadvantages of a more complex lead system. The purpose of this study was to compare defibrillation energy requirements of a single-lead unipolar defibrillator with a three-electrode system employing an additional lead in the coronary sinus.
Testing of a single-lead unipolar biphasic pulse defibrillation system versus a three-electrode system with an additional coronary sinus lead was performed in prospective, randomized fashion in 15 patients with a history of ventricular tachycardia or fibrillation. Ventricular fibrillation was induced with alternating current, and defibrillation threshold was measured by a pulse given 10 seconds after arrhythmia induction. The mean defibrillation threshold stored energy and mean leading edge voltage did not significantly differ between the two systems (11.3 +/- 5.9 J versus 9.9 +/- 5.2 J and 418 +/- 118 V versus 390 +/- 112 V, respectively; P > .4). Using either defibrillation system, all patients were successfully defibrillated by < 24 J and over half of patients by < 10 J.
A unipolar transvenous biphasic defibrillation system is an effective means of treating ventricular fibrillation. The added complexity of additional leads is not offset by any significant improvement in defibrillation efficacy or energy requirements. Given the simplicity and effectiveness of a single-lead system coupled with a small generator, placement of defibrillation systems may now approach the ease of pacemaker implantation.
近期一款单极经静脉除颤器原型的研发，使得设备植入如同永久起搏器植入一样简便。降低除颤能量需求将进一步减小除颤器发生器的尺寸，并提高类似起搏器放置方式的可行性。然而，如果要实现更低的除颤能量需要额外放置心内导联，那么更小发生器的潜在优势可能会被更复杂导联系统的劣势所抵消。本研究的目的是比较单极除颤器与采用一根额外冠状窦导联的三电极系统的除颤能量需求。
对15例有室性心动过速或颤动病史的患者，以前瞻性、随机方式进行了单极双相脉冲除颤系统与带有额外冠状窦导联的三电极系统的测试。用交流电诱发室颤，并在心律失常诱发后10秒给予脉冲测量除颤阈值。两个系统之间的平均除颤阈值存储能量和平均前沿电压无显著差异（分别为11.3±5.9 J对9.9±5.2 J以及418±118 V对390±112 V；P>.4）。使用任一除颤系统，所有患者均能以<24 J成功除颤，超过半数患者以<10 J成功除颤。
单极经静脉双相除颤系统是治疗室颤的有效手段。额外导联增加的复杂性并未被除颤疗效或能量需求的任何显著改善所抵消。鉴于单导联系统的简单性和有效性以及发生器体积小，除颤系统的放置现在可能接近起搏器植入的简便程度。
