Micra leadless pacemaker successfully implanted in first four patients

The Micra leadless pacemaker was successfully implanted in the first four patients to receive the device, according to a presentation at Cardiostim 2014.

The Micra transcatheter pacing system (Medtronic) is a leadless pacemaker that is approximately one-tenth the size of a traditional pacemaker. It is delivered directly into the heart through a catheter inserted in the femoral vein, according to a company press release.

Clemens Steinwender, MD, of Linz General Hospital, Austria, presented data on the first four patients enrolled in the global clinical trial for Micra. The trial is expected to enroll approximately 780 patients at 50 centers. All four patients had permanent atrial fibrillation with bradycardia.

The device was implanted successfully in all four patients (age range, 74 to 83 years; two women). At 1 month and 3 months, the researchers reported no complications, according to the release. The mean procedure time was 43 minutes, according to Steinwender’s presentation.

In other results, the mean R-wave amplitude was 11.98 mV at implant and 17.85 mV at 1 month; mean pacing threshold was 0.41 V at 0.24 ms at implant and 0.38 V at 0.24 ms at 1 month; and mean impedance was 712.5 ohm at implant and 770 ohm at 1 month, Steinwender said during the presentation.

“We are encouraged by these preliminary results and are hopeful that this less-invasive procedure will provide similar outcomes for all patients in the trial,” Steinwender stated in the release.

The Micra leadless pacemaker is investigational and is not yet approved in the United States.

For more information:

Steinwender C. Revolutionary techniques for implantable devices: Abstract 83/1. Presented at: Cardiostim 2014; June 18-21, 2014; Nice, France.

Disclosure: The study was funded by Medtronic. Steinwender reported receiving minor speaker honoraria from Abbott Vascular, Biotronik, Boston Scientific, Medtronic and St. Jude.