BACKGROUND: A dual-chamber leadless pacemaker (LP) system has been developed, employing distinct atrial leadless pacemaker (ALP) and ventricular leadless pacemaker (VLP) devices that maintain atrioventricular synchrony via wireless implant-to-implant (i2i) communication with each beat. A new i2i communication-free programming option was introduced to extend battery longevity and minimize unnecessary ventricular pacing by providing rate-modulated atrial pacing with backup ventricular pacing when needed (AAI(R) + VVI). The clinical safety and longevity improvement have not been evaluated commercially. METHODS: Patients indicated for dual-chamber pacing with new or existing dual-chamber LP implants were enrolled in this prospective, nonblinded, interventional study. Device diagnostics and battery longevity were interrogated before and after 6 months (6 M) of AAI(R) + VVI programming, with any programming-related complications or symptoms noted. Total ALP and VLP longevities were compared for DDD(R) at enrollment versus AAI(R) + VVI at 6 M. RESULTS: Dual-chamber LP systems in 139 patients at six centers were evaluated (76 ± 11 years; 53% male; PR 210 ± 56 ms; 80% sinus node dysfunction, 16% AV block of any degree), including 16% new and 84% existing implants (enrolled 7.9 ± 7.5 months postimplant). The 84 patients completing the study (n = 55 did not return) demonstrated a complication-free rate of 100.0% and a symptom-free rate of 97.6% (n = 2; fatigue, dizziness, shortness of breath). In the 32 patients enrolled with existing implants already in DDD(R) mode who also completed the 6 M visit, AAI(R) + VVI extended the longevities of ALPs by 93% (5.8 ± 1.1 to 11.1 ± 2.7 years, p < 0.001) and VLPs by 61% (10.9 ± 2.1 to 16.9 ± 1.2 years, p < 0.001). CONCLUSION: Clinical use of AAI(R) + VVI programming in dual-chamber LPs over 6 M resulted in no complications, minimal symptoms, and significantly extended ALP and VLP battery longevities.
