Multicenter study of the safety and effects of magnetic resonance imaging in patients with coronary sinus left ventricular pacing leads

BackgroundMagnetic resonance imaging (MRI) in patients with left ventricular (LV) leads may cause tissue or lead heating, dislodgment, venous damage, or lead dysfunction.ObjectiveThe purpose of this study was to determine the safety of MRI in patients with LV pacing leads.MethodsProspective data on patients with coronary sinus LV leads undergoing clinically indicated MRI at 3 institutions were collected. Patients were not pacemaker-dependent. Scans were performed under pacing nurse, technician, radiologist, and physicist supervision using continuous vital sign, pulse oximetry, and ECG monitoring and a 1.5-T scanner with specific absorption rate <1.5 W/kg. Devices were interrogated pre- and post-MRI, programmed to asynchronous or inhibition mode with tachyarrhythmia therapies off (if present), and reprogrammed to their original settings post-MRI.ResultsMRI scans (n = 42) were performed in 40 patients with non-MRI conditional LV leads between 2005 and 2013 (mean age 67 ± 9 years, n = 16 [40%] women, median lead implant duration 740 days with interquartile range 125-1173 days). MRIs were performed on the head/neck/spine (n = 35 [83%]), lower extremities (n = 4 [10%]), chest (n = 2 [5%]), and abdomen (n = 1 [2%]). There were no overall differences in pre- and post-MRI interrogation LV lead sensing (12.4 ± 6.2 mV vs 12.9 ± 6.7 mV, P = .38), impedance (724 ± 294 Ω vs 718 ± 312 Ω, P = .67), or threshold (1.4 ± 1.1 V vs 1.4 ± 1.0 V, P = .91). No individual LV lead changes required intervention.ConclusionMRI scanning was performed safely in non-pacemaker-dependent patients with coronary sinus LV leads who were carefully monitored during imaging without clinically significant adverse effect on LV lead function.