Tedder M, Anstadt M P, Tedder S D, Revishvili A S, Hegde S S, Lowe J E
Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710.
ASAIO J. 1993 Jul-Sep;39(3):M711-4.
The insulation of implantable cardioverter-defibrillator (ICD) sensing leads can fracture, causing device malfunction. Before March 1989, 32 patients received silicon CPI K54 sensing leads. Of these, four (12.5%) experienced discharges while in sinus rhythm. Subsequent ICD interrogation revealed that abdominal muscular contraction triggered discharges in two patients, but no abnormal sensing could be elicited in the other two patients. These patients subsequently were found to have sensing lead fractures. All sensing leads appeared intact radiographically but at reoperation were found to have insulation fractures 2-4 cm from the pin. The mechanism of fracture appears to be related to chronic intermittent lead compression between the anterior abdominal wall musculature and the ICD generator. Since March 1989, 134 patients have undergone ICD implantation with improved CPI 4312 sensing leads; none of these patients has experienced sensing lead fractures. The insulation of these leads is 2.5 times thicker than the K54 (1.0 mm vs. 0.4 mm). Patients with K54 sensing leads are at an increased risk for sensing lead insulation fracture and merit close surveillance. More importantly, sensing lead fractures must be considered in patients who present with inappropriate ICD discharges.
植入式心脏复律除颤器（ICD）感知导线的绝缘可能会发生断裂，从而导致设备故障。1989年3月之前，32例患者接受了硅质CPI K54感知导线。其中，4例（12.5%）在窦性心律时出现放电。随后的ICD问询显示，2例患者的腹部肌肉收缩触发了放电，但另外2例患者未引出异常感知。这些患者随后被发现存在感知导线断裂。所有感知导线在影像学上看起来完好无损，但再次手术时发现距针脚2 - 4厘米处存在绝缘层断裂。断裂机制似乎与前腹壁肌肉组织和ICD发生器之间的慢性间歇性导线受压有关。自1989年3月以来，134例患者接受了使用改进型CPI 4312感知导线的ICD植入；这些患者均未发生感知导线断裂。这些导线的绝缘层比K54导线厚2.5倍（1.0毫米对0.4毫米）。使用K54感知导线的患者发生感知导线绝缘层断裂的风险增加，值得密切监测。更重要的是，对于出现不适当ICD放电的患者，必须考虑感知导线断裂的情况。
