Medtronic’s Micra AV Leadless Pacemaker Evaluated in Real-World AccelAV Study

September 15, 2022—Medtronic announced the publication of a new finding from a real-world study demonstrating the effectiveness at 3 months of Micra AV leadless pacemaker as a therapy for patients with atrioventricular (AV) block. The company noted that this is the first prospective, multicenter study on the real-world performance of the Micra AV device.

Medtronic stated that Micra AV uses accelerometer-based 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.

Primary results of AccelAV were published online by Larry A. Chinitz, MD, et al in Heart Rhythm Journal.

According to Medtronic, the prospective, single-arm, multicenter study was composed of 152 patients (age, ≥ 18 years) enrolled at 20 centers in the United States and Hong Kong from June 2020 to September 2021. The patients in the study (mean age, 77 ± 11 years; 48% female) had a history of AV block and normal sinus function. A Micra AV was implanted in the right ventricle.

Of the 152 patients enrolled by investigators, 54 patients had complete AV block and normal sinus function. These more challenging cases were included a cohort to test AV synchrony performance.

Of these 54 more challenging patients, a subset of 20 patients were placed in the “Optimize” substudy to receive additional optimized programming to test improvements that could be gained beyond initial programming adjustments.

The investigators evaluated accelometer-based mechanical atrial sensing in the select cohort of patients with AV block with a leadless pacemaker implanted in the right ventricle.

As outlined by Medtronic, the Micra AV device showed the following results at 3 months postimplant:

• Sustained resting AV synchrony of 85.4% through 3 months.
• Improved ambulatory AV synchrony during activities of daily living. Optimized programming beyond initial adjustments, gained 10.5% more synchrony to achieve 82.6%.
• Improvement in AV synchrony, from optimized device programming, was most pronounced at elevated sinus rates (80-110 bpm).
• No need for upgrades to a dual chamber pacemaker or cardiac resynchronization therapy with a pacemaker.
• Improved quality of life from baseline, as measured by EQ-5D-3L questionnaire.

In January 2020, Medtronic announced FDA approval of Micra AV. The company announced it received CE Mark approval in June 2020. Approval in Japan was announced in January 2022.