Lee KJ, Kim BJ, Han MK, et al. - Among 2,046 individuals with atrial fibrillation, researchers explored the link between the level and variability of heart rate in the acute stroke period and stroke recurrence and mortality after acute ischemic stroke. From a multicenter prospective stroke registry database, they identified acute patients with ischemic stroke who had atrial fibrillation and were hospitalized within 48 hours of stroke onset. A total of 102 had a stroke recurrence, and 440 died during the first year after stroke. The mean heart rate during the acute stroke period was not correlated with stroke recurrence in patients with atrial fibrillation hospitalized for acute ischemic stroke, but was related to mortality (nonlinear, J-shaped association). Concerning variation in heart rate, the correlations between heart rate and outcomes were not observed.