Diagnostics & Imaging Week

Medtronic (Minneapolis) reported the start of an international clinical study to confirm the safety and efficacy of the EnRhythm MRI SureScan pacing system, saying that it is the first pacemaker system to be developed and tested specifically for safe use in MRI machines under specified scanning conditions.

The pacing system consists of the dual-chamber SureScan pacemaker and CapSureFix MRI SureScan pacing leads. The first clinical trial devices were recently implanted in Europe. All patients in the trial will receive an EnRhythm MRI SureScan pacing system, and approximately half of the participants will receive MRI scans; the trial’s first MRI scans will occur approximately two to three months after device implant. The study will compare the electrical and diagnostic system performance, as well as complication rates, among patients in both groups. The expected study duration is approximately 24 months.

The EnRhythm MRI SureScan pacemaker includes modified hardware to minimize the level of energy transmitted through the lead/device connection point. The pacemaker also includes a new SureScan feature that can be programmed “on” before an MRI scan to eliminate the impact of MRI-generated electrical noise, which can prevent necessary pacing therapy or cause the device to oversense and deliver unnecessary pacing therapy. When the SureScan feature is on, the device’s data collection and monitoring functions are temporarily suspended, while allowing the device to continue providing asynchronous pacing if needed.

“MRI safety is an important issue,” said Torsten Sommer, chief of the cardiovascular section of the radiology department, University of Bonn (Bonn, Germany), and European lead radiology investigator for the clinical trial. “It is critical to protect patients from electromagnetic fields that could contribute to a loss of pacing therapy. The only sure way to do this is to study a pacing system that was designed specifically for use in MRI systems.”