DISCUSSION
RECURRENCES, RECURRENCE
In this study, in patients with recent‐onset AF presenting at the ED, a delayed cardioversion strategy translated into a more optimal rate control during AF recurrences compared to early cardioversion without significant group‐differences in baseline or adjusted use of rate control medication. With a delayed cardioversion strategy, median heart rate at AF recurrence was lower as were peak heart rates. Apart from the randomized treatment, heart rate at presentation was independently associated with heart rate during AF recurrences.Aiming for optimal rate control in AF patients to achieve symptom alleviation remains a main pillar of AF treatment strategies.First, a lower heart rate at the index visit was independently associated with lower median heart rate during recurrences in both randomization arms. Interestingly, these patients with lower heart rate during the index visit did not use more rate control medication compared to those with higher heart rates at the index visit. Although beta blocker dosage was numerically higher in those with optimal heart rate at index, the proportion of patients using beta blocker medication was significantly larger in those with nonoptimal heart rates. This suggests that the heart rate during AF recurrences reflects the typical heart rate during AF for a given patient rather than the effect of rate control medication alone.As one of the main findings of this manuscript, we describe significantly lower maximum heart rates during recurrences in the delayed cardioversion group. Although we did not find any statistically significant differences in rate control medication use, dosage or adaptation between the early and delayed cardioversion group, numerically more patients in the delayed cardioversion group received rate control drugs at higher dosage or had their rate control medication adjusted. Indeed, in the delayed cardioversion group there was more focus on titrating rate control medication in the initial phase already. Although on a group level significant differences are absent, a combination of these factors may make a difference in the individual patient. Moreover, a potential power problem due to the small sample sizes should be kept in mind. Nonetheless, our study showed that titration of rate control medication is still suboptimal in many patients, and a more personalized titration of rate control medication based on heart rate, possibly guided by mHealth supported remote heart rate and rhythm monitoring, could achieve better rate control in all patients.In addition to a combination of (1) a numerically higher number of patients with lower heart rates at index visit and (2) numerically more index use and adaptation of rate control medication, also the development of better coping mechanisms may have determined rate during AF recurrences in the delayed cardioversion group. Whilst both groups have had reassuring information about the often transient and self‐terminating nature of recent‐onset AF, patients in the delayed cardioversion group have been exposed to AF‐related symptoms for a longer time initially, which allows them to get to learn their AF and even experience spontaneous conversion of AF, which helps them to develop possible coping mechanisms. This may result in less stress and consequently in lower heart rates during AF compared to those in the early cardioversion group.Irrespective of the involved mechanisms, a delayed cardioversion strategy may represent a useful and effective approach to optimize rate control in recent‐onset AF patients. To further harmonize the optimized rate control in the delayed cardioversion group, the mHealth approach used in this study could be transferred from an observational to an active telemonitoring system to allow early identification of actionable data (too slow or too fast heart rate during AF recurrence) and integration of this data into clinical decision pathways enabling faster responses and real time guidance of rate and rhythm control medication adaptation.