Data Published for Medtronic's Micra Transcatheter Pacing System

June 22, 2015—Medtronic plc announced that study results for its Micra transcatheter pacing system (TPS) were published online ahead of print by Philippe Ritter, MD, et al in the European Heart Journal. The Micra TPS global clinical trial results demonstrated that the miniaturized pacemaker met initial safety and performance measures in its global clinical trial, advised the company.

The data were also reported at a late-breaking clinical trials session at the European Heart Rhythm Association’s EuroPace-CardioStim 2015 conference being held June 21–24 in Milan, Italy. In May, data from the trial were presented during a late-breaking clinical trials session at Heart Rhythm 2015, the Heart Rhythm Society’s 36th Annual Scientific Sessions, in Boston, Massachusetts.

In Medtronic’s press release, Dr. Ritter, who served as principal investigator of the Micra TPS trial, commented, “The initial results for this novel device are quite promising and similar to results seen with conventional pacemakers. Patients in this study have fared very well, and if the strong safety and performance profile of the Micra TPS continues with more patients and over the long term, this transcatheter pacing therapy will prove to be a simpler, less-invasive pacemaker option while maintaining therapy effectiveness.” Dr. Ritter is a cardiologist at University Hospital of Bordeaux in France.

According to Medtronic, 100% of the first 140 patients who received the device in the trial were successfully implanted. At 1- and 3-month follow-up, all patients had mean electrical pacing measurements within expected ranges.  

The company noted that the implantations in these 140 patients were performed by 37 physicians at 23 sites across Asia-Pacific, Europe, and the United States. The patients were diverse in age (21–94 years), weight (41–148 kg), and residence (from Asia-Pacific, Europe, and the United States). Patients considered to be at high risk also participated in the study, including patients with lung disease and pulmonary hypertension. 

The patients were followed for an average of 1.9 months. Eight patients experienced a serious adverse event, and most of these were easily managed; only two patients (1.4%) experienced events that resulted in prolonged hospitalization. This rate is in line with rates observed in studies of traditional pacemakers. There were no infections or dislodgments, no events required surgical reoperation or resulted in death, and there were no unanticipated serious adverse device events (assumed < 5%).

Testing of electrical performance at 3 months showed the pacing threshold was lower (0.51 V at 0.24 ms) than the prespecified performance objective (< 2 V at 0.24 ms), resulting in an expected average longevity of at least 10 years.

The Micra TPS was commercially launched in Europe earlier in June. In April, the company announced CE Mark approval for the device based on data from the Medtronic Micra TPS Global Clinical Trial. The trial is ongoing and will continue to evaluate the safety and efficacy of the device through a single-arm, multicenter study that has enrolled more than 700 patients at 56 centers in 19 countries. In the United States, the Micra TPS is an investigational device and not yet approved for commercial use, advised the company.