FDA Approves Medtronic's Micra AV to Treat Atrioventricular Block
January 21, 2020—Medtronic announced it has received FDA approval of Micra AV, the company’s small 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 are impaired. Medtronic will begin training field personnel and physicians and will activate a limited number of implanting centers in the coming weeks. A full commercial launch is anticipated later this spring.
Medtronic's Micra AV is identical in size and shape to the original Micra TPS transcatheter pacing system, which was approved by the FDA in 2016 as a leadless pacemaker option for patients who only require pacing in the right ventricle. However, the new device has several additional internal atrial sensing algorithms that 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. Micra does not require leads or a surgical "pocket" under the skin, noted Medtronic.
In the company's announcement, cardiac electrophysiologist Larry Chinitz, MD, Director, NYU Langone’s Heart Rhythm Center, New York, New York, commented, "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.
"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."
The Micra AV approval is based on data from the MARVEL 2 study of Micra atrial tracking using a ventricular accelerometer that evaluated the safety and effectiveness of accelerometer-based atrial sensing algorithms. The study evaluated the ability of the device’s internal sensor to monitor and detect atrial contractions and enable coordinated pacing between the atrium and ventricle, thereby providing AV synchrony.
According to Medtronic, MARVEL 2 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 (38/40 [95%] patients) than VVI pacing (0 patients; P < .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.
In November 2019, results from the study were presented at the American Heart Association 2019 Scientific Sessions and published simultaneously by Clemens Steinwender, MD, et al in Journal of the American College of Cardiology: Clinical Electrophysiology (2020;6:94–106).