Abstract Funding Acknowledgements Type of funding sources: Private company. Main funding source(s): Medtronic Background Recently published real-world data showed that Micra leadless pacemaker implanted in the right ventricle can provide atrioventricular (AV) synchronous pacing by accelerometer-based mechanically sensing atrial contractions in patients with a high pacing burden (1). Routinely performed programming optimization of several novel parameters (particularly concerning the A3 and A4 windows) is key to improving AV synchrony (AVS). Purpose This project aims to define optimal programming recommendations for defined patient profiles. Methods An Experts Panel (ExpP), made up of 11 electrophysiologists from high-volume centers (37±17 Micra AV procedures/year) contributing to the Medtronic Micra AV prospective Post Approval Registry (PAR), was assembled to share their opinion about the optimal programming strategy to improve AVS in patients with: 1) slow sinus rhythm and high degree AV block, 2) fast sinus rhythm and high degree AV block, 3) intermittent AV-block. The following steps were followed: - Data from Micra AV PAR database were retrospectively analyzed and shared with ExpP. - An online survey was completed by the ExpP to evaluate their current programming strategy, based on PAR data. - After a face-to-face meeting to discuss the survey results, a second survey round was completed to reach consensus on the optimal programming strategy. Agreement was considered reached when >75% of responders did not disagree. Results Specific detailed programming recommendations have been developed for the three different patient profiles (Figure 1). Most importantly, it was agreed that Auto A3 Threshold and tracking check should be turned off in all patients, AV conduction mode switch should be turned off in all patients with high degree AVB, and the lower rate should be programmed in general to 50bpm. In addition, the following general recommendations were agreed on by the ExpP: - A pre-implant echocardiogram with a particular focus on diastolic function should always be performed to identify patients who may benefit from Micra AV implantation. - Micra AV auto-setup should always be performed at implant. - Before discharge, basic adjustments based on results of the Manual Atrial. Mechanical (MAM) test, patient activity level, and age should be performed. - At each follow-up visit, fine-tuning programming based on patient feedback, device data (in particular %AM-VP) and performance of a MAM Test. Conclusions An ExpP of Micra AV implanters agreed on general recommendations for Micra AV patients’ management before implant and during follow-up. Specific programming recommendations for patients with slow sinus rhythm and high degree AV block, fast sinus rhythm and high degree AV block, and intermittent AV block have been developed. A validation phase will show if the application of these indications in clinical practice may improve AVS.