Higgins John V, Gard Joseph J, Sheldon Seth H, Espinosa Raul E, Wood Christopher P, Felmlee Joel P, Cha Yong-Mei, Asirvatham Samuel J, Dalzell Connie, Acker Nancy, Watson Robert E, Friedman Paul A
Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota.
Pacing Clin Electrophysiol. 2014 Oct;37(10):1284-90. doi: 10.1111/pace.12419. Epub 2014 May 9.
Abandoned cardiovascular implantable electronic device (CIED) leads remain a contraindication to magnetic resonance imaging (MRI) studies, largely due to in vitro data showing endocardial heating secondary to the radiofrequency field. We tested the hypothesis that abandoned CIED leads do not pose an increased risk of clinical harm for patients undergoing MRI.
This single-center retrospective study examined the outcomes of patients who had device generators removed before MRI, rendering the device leads abandoned. Information was gathered through chart review. Data collected included lead model, pacing threshold before MRI, anatomic region examined, threshold data after generator reimplantation, and clinical patient outcome.
Patients (n = 19, 11 men and eight women) ranged in age from 19 to 85 at the time of MRI. There was a mean of 1.63 abandoned leads at the time of imaging; none of the leads were MRI conditional. Of the three implantable cardioverter defibrillator (ICD) leads, two of three were dual coil. Most (31/35) of the scans performed were of the central nervous system, including head and spinal imaging. There were no adverse events associated with MRI in any of these patients with abandoned leads within 7 days of the scan. No lead malfunctions or clinically significant change in pacing thresholds were noted with generator reimplantation.
The use of MRI in patients with abandoned cardiac device leads appears feasible when performed under careful monitoring, with no adverse events, although the experience is small. MRI did not affect the function of leads that were subsequently reconnected to a cardiac device.
废弃的心血管植入式电子设备（CIED）导线仍然是磁共振成像（MRI）检查的禁忌证，这主要是由于体外数据显示射频场会导致心内膜发热。我们检验了这样一个假设，即废弃的CIED导线不会给接受MRI检查的患者带来更高的临床伤害风险。
这项单中心回顾性研究检查了在MRI检查前移除设备发生器从而使设备导线废弃的患者的结局。通过查阅病历收集信息。收集的数据包括导线型号、MRI检查前的起搏阈值、检查的解剖区域、发生器重新植入后的阈值数据以及患者的临床结局。
进行MRI检查时，患者（n = 19，11名男性和8名女性）年龄在19岁至85岁之间（平均年龄）。成像时平均有1.63根废弃导线；没有一根导线符合MRI条件。在三根植入式心律转复除颤器（ICD）导线中，三根中有两根是双线圈的。所进行的扫描中，大多数（31/35）是针对中枢神经系统的，包括头部和脊柱成像。在扫描后7天内，这些有废弃导线的患者中没有任何一人发生与MRI相关的不良事件。重新植入发生器后，未发现导线故障或起搏阈值有临床意义的变化。
在仔细监测下对有废弃心脏设备导线的患者使用MRI似乎是可行的，且没有不良事件发生，尽管经验有限。MRI并未影响随后重新连接到心脏设备的导线的功能。
