Clinical routine implantation of a dual chamber pacemaker system designed for safe use with MRI: a single center, retrospective study on lead performance of Medtronic lead 5086MRI in comparison to Medtronic leads 4592-53 and 4092-58.

AIMS: We report our experience concerning lead performance and re-surgery rate of the Medtronic EnRhythm MRI SureScan pacemaker system (MRI-PM) in comparison to standard pacemaker (PM) systems and leads used at our institution.
METHODS: All patients (except patients with transvenous left ventricular leads) with successful PM implantation performed at our institution from 1 March 2009 to 31 October 2009 were included in this analysis and followed until mid January 2010. Lead measurements (assessed at implantation, prehospital discharge interrogation (1st follow-up) and at the first scheduled out-patient follow-up (2nd follow-up) were compared between atrial leads 4592-53 cm and 5086MRI-52 cm (lead group 1), and between ventricular leads 4092-58 cm and 5086MRI-52 cm/-58 cm (lead group 2), respectively. Causes for re-operations were assessed and compared between patients with standard dual chamber PM (DC-PM) and the MRI-PM.
RESULTS: A total of 140 patients (VVI-PM: 36 patients; DDD-PM: 102 patients; biventricular PM: 1 patient) were successfully implanted with a PM within the implantation period. Two patients with transvenous left ventricular leads were excluded from further analysis. In an atrial position, lead 4592 was implanted in 51 patients and lead 5086MRI-52 cm was implanted in 40 patients, respectively. Ventricular leads were lead 4092-58 cm (64 patients) and lead 5086MRI (41 patients), respectively. Patients were followed for 26 ± 11 weeks. Comparison of lead measurements of lead group 1 showed significant differences for pacing impedance and pacing threshold at implantation, and for sensing at the 2nd follow-up. Comparison of lead measurements within lead group 2 showed significant differences for pacing impedance at implantation, for pacing threshold at the 1st follow-up, and for sensing, pacing threshold, and impedance at the 2nd follow-up. All assessed mean values were favorable for all leads at any follow-up. The number of re-operations was high in both dual chamber PM groups, but did not differ significantly between the two groups (DC-PM: 5 patients, 8.5%; MRI-PM: 5 patients, 13.2%).
CONCLUSION: Our study demonstrates favorable lead measurements of lead model 5086MRI in comparison to lead 4592 and 4092 in a short-term follow-up. The number of re-operations was higher in the MRI-PM group, but not statistically different in comparison with the standard dual chamber PM group.