Savouré Arnaud, Mechulan Alexis, Burban Marc, Olivier Audrey, Lazarus Arnaud
Rouen University Hospital, Rouen, France.
Clairval Private Hospital, Marseille, France.
Clin Med Insights Cardiol. 2015 Aug 12;9:85-90. doi: 10.4137/CMC.S24976. eCollection 2015.
The impact of magnetic resonance imaging (MRI) on pacemakers is potentially hazardous. We present clinical results from a novel MRI conditional pacing system with the capability to switch automatically to asynchronous mode in the presence of a strong magnetic field.
The IKONE (Assessment of the MRI solution: KORA 100™ and Beflex™ pacing leads system) study is an open-label, prospective, multicenter study aimed at confirming the safety and effectiveness of the system, when used in patients undergoing MRI of anatomical regions excluding the chest.
Primary eligibility criteria included patients implanted with the system, with or without a clinically indicated MRI. The primary endpoint was to confirm no significant change in pacing capture thresholds at 1 month after an MRI, with an absolute difference of ≤0.75 V between the pre- and 1-month post-MRI for both atrial and ventricular capture thresholds.
Out of 33 patients enrolled (mean age: 72.8 ± 11.4 years, 70% male, implant indication or device), 29 patients implanted with the MRI conditional system underwent an MRI 6-8 week postimplant. The study reached its primary endpoint: the mean absolute difference in pacing capture threshold at 1-month post-MRI versus pre-MRI was less than 0.75 V in the atrium (Δ = 0.18 ± 0.16 V, P-value < 0.001) and in the ventricle (Δ = 0.18 ± 0.22 V, P-value < 0.001). There were no adverse events related to the MRI procedure nor were there reports of patient symptoms or discomfort associated. MR image quality was of diagnostic quality in all patients.
Lead electrical performance as measured by difference in capture thresholds were not impacted by MRI. This first clinical evaluation of a novel MRI conditional system demonstrates it is safe and effective for use in out-of-chest, 1.5-T MR imaging.
磁共振成像（MRI）对起搏器的影响可能具有危险性。我们展示了一种新型MRI条件性起搏系统的临床结果，该系统能够在强磁场存在时自动切换到异步模式。
IKONE（MRI解决方案评估：KORA 100™和Beflex™起搏导线系统）研究是一项开放标签、前瞻性、多中心研究，旨在确认该系统在用于除胸部以外解剖区域进行MRI检查的患者时的安全性和有效性。
主要入选标准包括植入该系统的患者，无论是否有临床指征需要进行MRI检查。主要终点是确认MRI检查后1个月时起搏夺获阈值无显著变化，心房和心室夺获阈值在MRI检查前和检查后1个月之间的绝对差值≤0.75V。
在33名入组患者中（平均年龄：72.8±11.4岁，70%为男性，植入指征或设备），29名植入MRI条件性系统的患者在植入后6 - 8周接受了MRI检查。该研究达到了主要终点：MRI检查后1个月与检查前相比，心房起搏夺获阈值的平均绝对差值小于0.75V（Δ = 0.18±0.16V，P值<0.001），心室起搏夺获阈值的平均绝对差值小于0.75V（Δ = 0.18±0.22V，P值<0.001）。没有与MRI检查相关的不良事件，也没有关于患者症状或不适的报告。所有患者的MR图像质量均符合诊断要求。
通过夺获阈值差异测量的导线电性能不受MRI影响。对新型MRI条件性系统的首次临床评估表明，该系统用于胸部以外的1.5T MR成像安全有效。
