磁共振兼容起搏器行1.5 T磁共振扫描的安全性研究

Study on the safety of 1.5 T magnetic resonance imaging scan for magnetic resonance imaging compatible pacemaker

目的评价植入磁共振(MRI)兼容起搏器后行1.5 T MRI扫描的安全性及起搏系统的稳定性。方法2012年1月至2015年6月于新疆医科大学第一附属医院植入MRI兼容起搏器的患者为研究对象。观察患者行MRI扫描前、扫描后即刻以及扫描后1、3、12个月的起搏器系统稳定性及起搏阈值、感知、阻抗和电池寿命及临床不良事件。结果113例患者接受MRI扫描并按时完成各阶段随访,扫描过程中无心前区不适感、无误感知、无脉冲发生器重置、无起搏器导线脱位,除1例阵发性心房颤动(房颤)患者扫描中监测到房颤外其余患者未监测到心律失常。患者心房起搏阈值、感知,心室起搏阈值、感知在MRI扫描后各随访时间点与扫描前变化无临床意义。1例患者MRI扫描后12个月发生下壁心肌梗死,心室感知幅度较基线下降50%以上,其余患者随访未发现起搏阈值增加0.5 V以上、感知下降50%以上以及起搏器电池提前耗竭情况。心室导线阻抗MRI扫描后12个月与基线对比差异有统计学意义[(530.10±117.87)Ω对(547.76±122.00)Ω,P=0.001],随访期间无心房导线、心室导线阻抗<200Ω或>1500Ω。结论植入MRI兼容起搏器患者进行1.5 T MRI扫描时患者无不良事件发生,安全性好。

Objective To investigate the safety of 1.5 T magnetic resonance imaging(MRI)scan and the stability of pacing system after implantation of MRI compatible pacemaker.Methods From January 2012 to June 2015,113 patients with implantable MRI compatible pacemaker in The First Affiliated Hospital of Xinjiang Medical University who underwent 1.5 T MRI scan were selected.The pacemaker system stability and device parameters(pacing threshold,sensing,impedance and battery life)and clinical adverse events were assessed before,immediately after,1,3,and 12 months after MRI scanning,and long-term follow-up was conducted.Clinical adverse events were also recorded.Results One hundred and thirteen patients underwent MRI scans and completed follow-up at all stages on time.No discomfort in the precordial area,no error perception,no pulse generator reset,and no pacemaker lead dislocation were observed during MRI scan process.Arrhythmia was not detected in other patients except for atrial fibrillation(AF)during scanning in a patient with paroxysmal AF.Atrial pacing threshold and perception,ventricular pacing threshold and perception of various follow-up time points and preoperative changes after MRI scan were not clinically significant.One patient had inferior wall myocardial infarction 12 months after MRI scan,with a decrease of more than 50%in perception compared with baseline.No more than 0.5 V increase in pacing threshold,no more than 50%decrease in perception,and no premature pacemaker battery depletion were found in other patients during follow-up.There was significant differene in ventricular lead impedance between baseline and 12 months after MRI scan[(530.10±117.87)Ωvs.(547.76±122.00)Ω,P=0.001].During the whole follow-up period,there were no atrial and ventricular impedance<200Ωor>1500Ω.Conclusion Patients implanted with MRI compatible pacemakers who underwent 1.5 T MRI scan was safe and stable.