Artificial Atrial Fibrillation in the Dog

R-R interval sequences during artificial atrial fibrillation in dogs were studied in the same way as in patients in a previous study and compared with results obtained in dogs with spontaneous atrial fibrillation. Artificial atrial fibrillation was effected by right atrial stimulation in three closed-chest and one open-chest dog. The ventricular rhythm was studied by histograms and autocorrelograms. The ventricular dysrhythmia during artificial atrial fibrillation generally differed from that during true atrial fibrillation. Therefore the findings during artificial atrial fibrillation cannot be used without reservation to explain electrophysiological (or hemodynamic) phenomena in true atrial fibrillation.