Kühlkamp V, Dörnberger V, Khalighi K, Mewis C, Suchalla R, Ziemer G, Seipel L
Medical Department, Eberhard-Karls-University, Tübingen, Germany.
Pacing Clin Electrophysiol. 1998 Dec;21(12):2596-605. doi: 10.1111/j.1540-8159.1998.tb00036.x.
Even with the use of biphasic shocks, up to 5% of patients need an additional subcutaneous lead to obtain a defibrillation safety margin of at least 10 J. The number of patients requiring additional subcutaneous leads may even increase, because recent generation devices have a < 34 J maximum output in order to decrease their size. In 20 consecutive patients, a single element subcutaneous array lead was implanted in addition to a transvenous lead system consisting of a right ventricular (RV) and a vena cava superior lead using a single infraclavicular incision. The RV lead acted as the cathode; the subcutaneous lead and the lead in the subclavian vein acted as the anode. The biphasic defibrillation threshold was determined using a binary search protocol. Patients were randomized as to whether to start them with the transvenous lead configuration or the combination of the transvenous lead and the subcutaneous lead. In addition, a simplified assessment of the defibrillation field was performed by determining the interelectrode area for the transvenous lead only and the transvenous lead in combination with the subcutaneous lead from a biplane chest X ray. The intraoperative defibrillation threshold was reconfirmed after 1 week, after 3 months, and after 12 months. The mean defibrillation threshold with the additional subcutaneous lead was significantly (P = 0.0001) lower (5.7 +/- 2.9 J) than for the transvenous lead system (9.5 +/- 4.6 J). With the subcutaneous lead, the impedance of the high voltage circuit decreased from 48.9 +/- 7.4 omega to 39.2 +/- 5.0 omega. In the frontal plane, the interelectrode area increased by 11.3% +/- 5.5% (P < 0.0001) and in the lateral plane by 29.5% +/- 12.4% (P < 0.0001). The defibrillation threshold did not increase during follow-up. Complications with the subcutaneous electrode were not observed during a follow-up of 15.8 +/- 2 months. The single finger array lead is useful in order to lower the defibrillation threshold and can be used in order to lower the defibrillation threshold.
即使使用双相电击，仍有高达5%的患者需要额外植入皮下导线，以获得至少10焦耳的除颤安全裕度。由于新一代设备为了减小尺寸，最大输出功率<34焦耳，因此需要额外皮下导线的患者数量甚至可能增加。在连续20例患者中，除了由右心室（RV）和上腔静脉导线组成的经静脉导线系统外，还通过单一锁骨下切口植入了单元件皮下阵列导线。RV导线作为阴极；皮下导线和锁骨下静脉中的导线作为阳极。使用二分搜索协议确定双相除颤阈值。患者被随机分为以经静脉导线配置开始，还是以经静脉导线和皮下导线组合开始。此外，通过仅从双平面胸部X光确定经静脉导线以及经静脉导线与皮下导线组合的电极间面积，对除颤场进行简化评估。在1周、3个月和12个月后重新确认术中除颤阈值。额外皮下导线的平均除颤阈值（5.7±2.9焦耳）显著低于经静脉导线系统（9.5±4.6焦耳）（P = 0.0001）。使用皮下导线时，高压电路的阻抗从48.9±7.4欧姆降至39.2±5.0欧姆。在额面，电极间面积增加了11.3%±5.5%（P < 0.0001），在侧面增加了29.5%±12.4%（P < 0.0001）。在随访期间除颤阈值没有增加。在15.8±2个月的随访期间未观察到皮下电极的并发症。单指阵列导线有助于降低除颤阈值，可用于降低除颤阈值。
