SyncAV Post-Market Trial

The SyncAV Post-Market Trial is designed as a prospective, randomized, multi-center trial. The trial will require physicians to implant an Abbott CRT device and Abbott Quadripolar LV lead with any available right atrial and right ventricular leads. Sites will randomize subjects in a 1:1 ratio within 2 - 6 weeks post successful CRT implant: Arm 1 - SyncAV CRT programmed ON; Arm 2 - programmed fixed atrioventricular (AV) delay. For those subjects randomized to SyncAV programmed ON, sites will measure QRS duration with the subject's intrinsic rhythm (pacing OFF), at biventricular (BiV) pacing nominal settings, with various SyncAV programmed offsets, and at LV first 30 ms, RV first 30 ms and LV-only pacing with optimal SyncAV offsets. The site will then program the subject's device using the SyncAV offset that provided the narrowest QRS duration. For those subjects randomized to the fixed AV delay arm, sites will measure QRS duration with the subject's intrinsic rhythm (pacing OFF) and at BiV pacing nominal settings. Sites will then program the subject's device using BiV pacing nominal settings. Sites will collect data at baseline (before CRT implant), randomization, and at 3-month, 6-month, and 12-month visits. For subjects randomized to the SyncAV ON arm, sites will optimize the SyncAV feature again at 3 months and 6 months in the same manner as the randomization visit.