Medtronic has received FDA approval of Micra AV, which a press release describes as “the world’s smallest pacemaker with atrioventricular (AV) synchrony”; the pacemaker is indicated for the treatment of patients with AV block. The press release states that Medtronic “now offers the first and only FDA-approved leadless pacemaker portfolio, expanding the number of potential candidates for this ground-breaking technology in the USA”.
Identical in size and shape to the original Micra Transcatheter Pacing System (TPS), the Micra AV has several additional internal atrial sensing algorithms that are designed to 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.
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, comments: “Since revolutionising medicine with the first battery-powered cardiac pacemakers, Medtronic has continued to develop pioneering pacing technologies, culminating in the first miniaturised, leadless pacing portfolio for physicians and their patients. The introduction of Micra AV reinvents our own innovation, bringing the many benefits of leadless pacemakers to more patients.”