The FDA has just approved the smallest pacemaker with atrioventricular (AV) synchrony, the Micra AV. The device, intended to treat AV block, a condition typically requiring a dual-chamber pacemaker, is small enough to remain completely inside the heart. It doesn’t have any leads, nor any complications arising from them It looks the same as Medtronic’s Micra Transcatheter Pacing System, but features algorithms that can detect the movement of the heart and coordinate the pacing of the ventricle so it works efficiently in conjunction with the atrium. This is thanks to a built-in accelerometer with the pacemaker, which is used to sense the actual back and forth movement of the heart. “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, M.D., cardiac electrophysiologist and director of NYU Langone’s Heart Rhythm Center in New York City, in a Medtronic press release. “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.” Here’s some clinical study data regarding the Micra AV, according to Medtronic: 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. Source
