Medtronic has announced that it has received US Food and Drug Administration (FDA) approval of Micra AV, the world’s smallest pacemaker with atrioventricular (AV) synchrony.
Micra AV is indicated for the treatment of patients with AV block, a condition in which the electrical signals between the chambers of the heart (the atria and the ventricle) are impaired.
“With the approval of Micra AV, more pacemaker patients qualify for a new treatment option that offers the advantages of leadless pacing – including a minimally invasive implant procedure and a cosmetically invisible device,” said Larry Chinitz, cardiac electrophysiologist and director of NYU Langone’s Heart Rhythm Center in New York City, USA. “Although complications with traditional pacemakers are infrequent, when they occur, they’re expensive to treat and can be invasive for the patient. Real-world use of Micra has shown a 63% reduction in major complications compared to traditional pacemakers.”
Historically, patients with AV block have been treated with traditional dual-chamber pacemakers which are implanted in the upper chest, under the skin below the collar bone, and connected to the heart using thin wires called “leads.” Identical in size and shape to the original Micra Transcatheter Pacing System (TPS), Micra AV has several additional internal atrial sensing algorithms which detect cardiac movement, allowing the device to adjust pacing in the ventricle to coordinate with the atrium, providing “AV synchronous” pacing therapy to patients with AV block.
The Micra AV approval is based on data from the MARVEL 2 (Micra Atrial Tracking Using A Ventricular accELerometer) study, which evaluated the safety and effectiveness of accelerometer-based atrial sensing algorithms.
The study evaluated the ability of the Micra’s internal sensor to monitor and detect atrial contractions and enable coordinated pacing between the atrium and ventricle, thereby providing AV synchrony. Results from the study, presented at the American Heart Association 2019 Scientific Sessions and published simultaneously in JACC: Clinical Electrophysiology, showed the primary efficacy objective was met, with a significantly greater percentage of complete heart block patients with normal sinus rhythm having >70% AV synchrony during algorithm-mediated AV synchronous pacing (38 of 40 patients, 95%) than VVI pacing (0 patients, P<0.001 for proportion of patients with >70% synchrony). The study’s primary safety objective was also met, with no pauses or episodes of pacing-induced tachycardia reported during algorithm mediated AV synchronous pacing.
Medtronic will begin training field personnel and physicians, and will activate a limited number of implanting centres in the coming weeks, with full launch anticipated later this spring.
“Since revolutionising medicine with the first battery-powered cardiac pacemakers, Medtronic has continued to develop pioneering pacing technologies, culminating in the first miniaturized, leadless pacing portfolio for physicians and their patients,” said Rob Kowal, chief medical officer, vice president of medical affairs in the Cardiac Rhythm and Heart Failure division, which is part of the Cardiac and Vascular Group at Medtronic.