Five years ago, the FDA approved Medtronic’s Micra, the first leadless pacemaker to hit the US market. Touted as the world’s smallest pacemaker, the Medtronic device represented a major innovative leap in pacemaker technology. The device also became a golden example of how medical device manufacturers continue to push the boundaries of what is possible in medtech miniaturization.
Although St. Jude Medical was working on a leadless pacemaker around the same time (before it was acquired by Abbott Laboratories), that device never made it to the market and the Medtronic Micra is still the only leadless pacemaker in the United States.
Now, however, the FDA is reminding cardiac surgeons of the risk of serious complications if heart perforation occurs during a leadless pacemaker implant. Although cardiac perforation is a rare complication (occurring in approximately 1% of cases) of any pacemaker implant procedure, field data suggest that the risk of serious complications following cardiac perforation may be higher in patients receiving a Medtronic Micra cordless pacing system than a traditional transvenous pacing system. pacemaker.
The agency said it wrote a letter to health care providers this week as a reminder. The letter also encourages physicians to report cardiac perforations from leadless pacemakers and related complications to Medtronic and FDA. The agency said it is working with Medtronic to evaluate information from all available sources on this matter.
The FDA approved the Medtronic Micra Transcatheter Pacing System in April 2016 with a mandatory post-approval study to obtain more information and help assess the continued safety and effectiveness of the device. This pacemaker system does not require wired leads to make an electrical connection between the pulse-generating device and the heart.
Difference between Medtronic Micra and traditional pacemakers
Pacemakers are surgically implanted medical devices that generate electrical impulses to treat slow heartbeats, and nearly 1 million people worldwide have a pacemaker implanted each year. The lead in a traditional single-chamber pacemaker extends from the pacemaker generator, which is implanted under the skin near the collarbone, through a vein and terminates in direct contact with the right ventricular wall of the heart. The lead delivers electrical pulses from the generator to the right ventricle and helps coordinate heartbeat timing. Although the Medtronic Micra System works similarly to pacemakers with leads to regulate the heart rate, the self-contained, inch-long wireless device is implanted directly into the right ventricle of the heart, as shown in the image below.