Minneapolis Heart Institute Foundation, Minneapolis, MN, USA.
Heart Rhythm. 2012 May;9(5):742-9. doi: 10.1016/j.hrthm.2011.12.019. Epub 2011 Dec 28.
The Riata family of implantable cardioverter-defibrillator leads (St Jude Medical, Sylmar, CA) appears prone to a unique failure mechanism whereby the conductor cables wear through the silicone insulation from inside-out and are seen outside the lead body (externalized conductors).
To assess the extent of Riata lead damage associated with inside-out insulation defects and their clinical consequences.
In September 2011, we searched the U.S. Food and Drug Administration's Manufacturers and User Defined Experience medical device database for reports describing Riata lead failures that had been analyzed by the manufacturer.
The Manufacturers and User Defined Experience search identified 105 leads that had inside-out insulation defects. Eight-French single-coil Riata leads accounted for a higher-than-expected proportion (25.7%) of the leads with this defect. A total of 226 insulation defects were found in the 105 leads (2.2 defects per lead), including 143 inside-out defects (1.4 defects per lead). The most common location of insulation defects was distal to the proximal coil (n = 108). Twenty-eight leads (26.7%) had inside-out insulation defects underneath the shocking coils. Of 43 leads whose cables were assessed for the integrity of the ethylene-tetrafluoroethylene cable coating, 22 (51.2%) were found to be abraded, exposing the conductor surfaces. On X-ray radiography or fluoroscopy, 7 leads were found to have externalized cables; 2 of these leads had no electrical abnormalities, while 4 exhibited noise or increased impedance. Inappropriate shocks were experienced by 31 of the 105 patients (29.5%).
Riata leads that have inside-out insulation defects often have multiple defects, including additional inside-out abrasions along the body of the lead and beneath the shocking coils. Eight-French single-coil Riata models may be more prone to externalized cables than are dual-coil and 7-F designs. Externalized cables are but one manifestation of interior insulation damage. Our findings question the durability of the ethylene-tetrafluoroethylene cable coating on exposed cables.
植入式心律转复除颤器导联里的 Riata 系列（圣犹达医疗公司，西尔玛，加利福尼亚）似乎容易出现一种独特的故障机制，即导体电缆从内到外磨损硅树脂绝缘层，然后在导联体外部（导体外露）被看到。
评估与内-外绝缘缺陷相关的 Riata 导联损坏的程度及其临床后果。
2011 年 9 月，我们在美国食品药品监督管理局的制造商和用户定义经验医疗器械数据库中搜索了制造商分析过的描述 Riata 导联故障的报告。
制造商和用户定义经验搜索确定了 105 个具有内-外绝缘缺陷的导联。8 法式单匝 Riata 导联占具有该缺陷的导联的比例（25.7%）高于预期。在 105 个导联中发现了 226 个绝缘缺陷（每个导联 2.2 个缺陷），包括 143 个内-外缺陷（每个导联 1.4 个缺陷）。绝缘缺陷最常见的位置是在近端线圈的远端（n = 108）。28 个导联（26.7%）在电击线圈下方有内-外绝缘缺陷。在评估乙烯-四氟乙烯电缆涂层完整性的 43 个导联中，有 22 个（51.2%）发现磨损，暴露了导体表面。在 X 射线射线照相或荧光透视检查中，发现 7 个导联的电缆有外露；其中 2 个导联没有电气异常，而 4 个导联表现为噪声或阻抗增加。在 105 名患者中，有 31 名（29.5%）经历了不适当的电击。
具有内-外绝缘缺陷的 Riata 导联通常有多个缺陷，包括沿导联体和电击线圈下方的额外内-外磨损。8 法式单匝 Riata 模型可能比双匝和 7 法式设计更容易出现电缆外露。电缆外露只是内部绝缘损坏的一种表现。我们的发现对暴露电缆上的乙烯-四氟乙烯电缆涂层的耐用性提出了质疑。
