Safety and efficacy of a new magnetic resonance imaging-compatible pacing system: early results of a prospective comparison with conventional dual-chamber implant outcomes.

BACKGROUND

A new pacing system has been designed and tested preclinically for safe use in the magnetic resonance imaging (MRI) environment. Experience with this innovative system has not yet been reported.

OBJECTIVE

The purpose of this study was to verify the safety and effectiveness of this newly designed system compared to conventional DDD implant outcomes.

METHODS

Over an 11-month period, 107 consecutive patients (71 men and 36 women; age 72.6 +/- 8.5 years) were implanted with either the MRI system (n = 50; MRI group) or a dual-chamber, active-fixation lead (Medtronic 4076) non-MRI system (n = 57; DDD group). Data were collected at implant and during postoperative follow-up at 1, 3, 6, and 12 months. Procedural and fluoroscopic times at implant, as well as lead measurements, handling characteristics, and procedural-related complications, were prospectively analyzed.

RESULTS

The implantation success rate in both groups was 100%. Cephalic access was 63% for MRI patients and 70% for DDD patients (P = NS). Follow-up was obtained for all patients (median 6.8 months, range 3-12 months). At implant and at the end of follow-up, stimulation thresholds, sensing, and impedance were acceptable. No cases of high pacing thresholds or inadequate sensing were noted. No complications occurred, and no patient experienced subsequent lead displacement.

CONCLUSION

This prospective, controlled study provides strong evidence that the feasibility and safety of this novel technology compare favorably with those of the conventional technique.