Temperature-Based Rate Response in a Leadless Pacemaker System.
Academic Article
Overview
abstract
BACKGROUND: A new dual chamber leadless pacemaker (DR-LP) system, comprised of two implantable devices in the right ventricle and right atrium, uses a less common temperature-based rate-response sensor. There is a need to understand the effectiveness of the rate response during exercise in both the ventricular (VR-LP) and atrial (AR-LP) devices. OBJECTIVE: Determine if temperature-based rate-responsive pacing is proportional to metabolic workload during an exercise test in a leadless pacemaker system. METHODS: After 6-weeks post-implant, we administered a treadmill exercise protocol to eligible subjects concurrently enrolled in the LEADLESS II-Phase 2 (NCT04559945) and Aveir DR i2i studies (NCT05252702). Programmed settings were optimized after a prior six-minute walk test. We evaluated the ventricular and atrial rate-response sensors in subjects implanted with the VR-LP and DR-LP system, respectively. For each device, the normalized slopes of sensor-indicated rate versus metabolic workload were aggregated across all analyzable patients. If the mean slope's 95% confidence interval (CI) fell within the pre-specified 0.65 and 1.35 acceptance range, the rate response was considered proportional to metabolic demand. RESULTS: Seventeen (17) subjects had a mean ventricular rate-response slope of 0.93 ± 0.29 (CI: 0.78, 1.08), which fell within the acceptance criteria (p = 0.001). Twenty (20) subjects had a mean atrial rate-response slope of 0.91 ± 0.28 (CI: 0.78, 1.05), also falling within the pre-specified criteria (p<0.001). CONCLUSIONS: The temperature-based sensor in a dual-chamber leadless pacemaker system was shown to be effective at modulating pacing rate in response to increased metabolic demand for right ventricular and atrial devices.
