Leadless pacemakers as the Medtronic Micra AV, have improved cardiac pacing by reducing complications associated with traditional systems. However, achieving high atrioventricular synchrony (AVS) remains a challenge, especially in patients with a high pacing burden. This prospective study enrolled 30 patients to assess the role of echocardiographic parameters in predicting AVS postimplantation. AVS was evaluated via 24-h Holter monitoring, with a median AVS of 67.9% ± 9.6%. Right atrial function, particularly the tricuspidal E wave deceleration time, emerged as the only independent predictor of AVS (p = 0.03), with an AUC of 0.77. These findings suggest that pre-implantation echocardiographic assessment of right atrial parameters could aid in selecting patients who would benefit most from Micra AV. Further studies with larger cohorts and extended follow-ups are warranted.