Jacobsson J, et al. - Researchers focused on the influence of atrial fibrillation (AF) and biventricular pacing (BivP) on the risk of death or heart transplantation at 10-years of follow-up among cardiac resynchronization therapy (CRT)-recipients. For this purpose, they retrospectively collected data from patient registers, medical records and preoperative electrocardiograms at a Swedish tertiary referral center. Findings revealed a common prevalence of AF-history as well as its link with poor outcome in CRT-recipients. No independent prediction of mortality was enabled by AF-history and rather, it was probably only a marker of a more severe underlying disease. Poor outcome was independently predicted by BivP ≤ 98% during first-year of CRT-treatment, and therefore, the use of 98% threshold of BivP was further supported as well as recommended to be achieved in order to maximize the benefits of CRT.