What Is the Optimal Heart Rate in Atrial Fibrillation?
Unfortunately, there is a lack of uniform definition of heart rate control in atrial fibrillation, although it is generally agreed that rate control must exist both at rest and during normal daily activities. Patients in atrial fibrillation demonstrate greater maximum and minimum heart rates during normal daily activities than do similar patients in sinus rhythm, and the assessment of an “optimal” heart rate in patients with atrial fibrillation must take into account the potential need for a slightly faster resting heart rate at rest than might be seen in sinus rhythm that results from the loss of the atrial contribution to ventricular filling. There have been several small trials of individual negative chronotropic agents for ventricular rate control in persistent atrial fibrillation that used exercise testing as a goal to determine optimal heart rate control. These studies have been reviewed recently by Bjerregaard and coworkers.43 The predominant drugs studied were digoxin, various
