Sharif M N, Wyse D G, Rothschild J M, Gillis A M
Department of Medicine, University of Calgary, Alberta, Canada.
Am J Cardiol. 1998 Sep 1;82(5):600-3. doi: 10.1016/s0002-9149(98)00414-7.
It has been suggested that a decrease in lead impedance may predict pacing lead failure, but there is limited prospective data about the relation of changes in lead impedance over time to lead performance. We monitored changes in lead impedance through implantable pulse generators with real-time telemetry data capability in 105 patients with Medtronic 4012 leads (n = 38) and Medtronic 4004 leads (n = 67). Pacing lead failure was documented by serial ambulatory electrocardiographic monitoring or intensified pacemaker clinic surveillance. A significant decrease in lead impedance was observed in patients with Medtronic 4012 and Medtronic 4004 leads with documented lead failure, whereas lead impedance remained stable over time in patients without documented lead failure. The sensitivity and specificity of a lead impedance decrease of > or =15% to predict lead failure were 69% and 70%, respectively. The sensitivity and specificity of a lead impedance decrease of > or =30% to predict lead failure were 36% and 90%, respectively. The positive and negative predictive values for a lead impedance decrease of > or =15% were 54% and 81%, respectively, and for a lead impedance decrease of > or = 30% were 65% and 73%, respectively. Thus, small decreases in lead impedance may identify failing leads. Serial measurement of pacing lead impedance over time is a useful tool to monitor pacing lead performance.
有人提出，起搏导线阻抗降低可能预示着起搏导线故障，但关于导线阻抗随时间变化与导线性能之间关系的前瞻性数据有限。我们通过具有实时遥测数据功能的植入式脉冲发生器，对105例使用美敦力4012导线（n = 38）和美敦力4004导线（n = 67）的患者的导线阻抗变化进行了监测。通过连续动态心电图监测或加强起搏器门诊监测记录起搏导线故障。在记录有导线故障的使用美敦力4012导线和美敦力4004导线的患者中，观察到导线阻抗显著降低，而在无导线故障记录的患者中，导线阻抗随时间保持稳定。导线阻抗降低≥15%预测导线故障的敏感性和特异性分别为69%和70%。导线阻抗降低≥30%预测导线故障的敏感性和特异性分别为36%和90%。导线阻抗降低≥15%的阳性预测值和阴性预测值分别为54%和81%，导线阻抗降低≥30%的阳性预测值和阴性预测值分别为65%和73%。因此，导线阻抗的小幅降低可能提示导线故障。随时间对起搏导线阻抗进行连续测量是监测起搏导线性能的有用工具。
