Shenthar Jayaprakash, Milasinovic Goran, Al Fagih Ahmed, Götte Marco, Engel Gregory, Wolff Steven, Tse Hung-Fat, Herr Julie, Carrithers John, Cerkvenik Jeffrey, Nähle Claas Philip
Electrophysiology Unit, Department of Cardiology, Sri Jayadeva Institute of Cardiovascular Sciences and Research, Jayanagar, Bangalore, India.
Pacemaker Center, Clinical Center of Serbia, Belgrade, Serbia.
Heart Rhythm. 2015 Apr;12(4):759-65. doi: 10.1016/j.hrthm.2014.12.035. Epub 2014 Dec 30.
Magnetic resonance imaging (MRI) can be safely performed in patients with magnetic resonance (MR)-conditional pacemaker systems but remains relatively contraindicated with non-MR-conditional pacemaker systems.
The purpose of this study was to evaluate the safety of MRI without positioning restrictions in patients with an MR-conditional pacemaker and currently a non-MR-conditional Medtronic CapSureFix Novus 5076 lead(s).
The study randomized 266 patients in a 2:1 ratio to the MRI group (177 patients) or to the control group (89 patients). At 9-12 weeks postimplant, the MRI group underwent MRI at 1.5 T. Primary end points were MRI-related complication-free rate and noninferiority of the MRI group compared to the control group with regard to the proportion of patients with an increase of ≤0.5 V in right atrial (RA) and right ventricular (RV) pacing capture thresholds from immediately before MRI to 1-month after MRI.
No MRI-related complications occurred in 156 MRI-scanned patients who were followed through 1-month post-MRI. Differences in the proportion of patients with ≤0.5 V pacing capture threshold changes from pre-MRI to 1-month post-MRI were minimal between the groups for RA (proportions of 100% in both groups; a P value cannot be calculated) and RV leads (proportions of 99.3% in the MRI group and 100% in the control group; noninferiority test, P < .0001). Proportions of patients with acceptable sensing amplitude changes from pre-MRI to 1-month post-MRI were also similar between the 2 groups for RA and RV leads (noninferiority test, P < .0001 and P = .0004, respectively). No arrhythmias occurred during MRI.
MRI scans can be performed safely without positioning restrictions in patients with Medtronic CapSureFix Novus 5076 leads connected to an MR-conditional pacemaker.
磁共振成像（MRI）可在配备磁共振（MR）兼容起搏器系统的患者中安全进行，但对于非MR兼容起搏器系统仍相对禁忌。
本研究的目的是评估在配备MR兼容起搏器且目前使用非MR兼容美敦力CapSureFix Novus 5076导线的患者中，不受体位限制进行MRI检查的安全性。
该研究以2:1的比例将266例患者随机分为MRI组（177例患者）和对照组（89例患者）。植入后9至12周，MRI组在1.5T下接受MRI检查。主要终点是MRI相关无并发症发生率，以及MRI组与对照组相比，从MRI检查前到MRI检查后1个月，右心房（RA）和右心室（RV）起搏捕获阈值升高≤0.5V的患者比例的非劣效性。
156例接受MRI扫描的患者在MRI检查后随访1个月期间未发生与MRI相关的并发症。两组之间，从MRI检查前到MRI检查后1个月，RA起搏捕获阈值变化≤0.5V的患者比例差异极小（两组比例均为100%；无法计算P值），RV导线也是如此（MRI组比例为99.3%，对照组为100%；非劣效性检验，P<.0001）。两组之间，从MRI检查前到MRI检查后1个月，RA和RV导线感知幅度变化可接受的患者比例也相似（非劣效性检验，P分别为<.0001和.0004）。MRI检查期间未发生心律失常。
对于连接到MR兼容起搏器的美敦力CapSureFix Novus 5076导线的患者，可以不受体位限制安全地进行MRI扫描。
