Discrimination of atrial fibrillation from regular rhythms by spatial precision of activation direction

This study tests the hypothesis that atrial fibrillation (AFib) can be discriminated from regular atrial rhythms by the variation in local activation direction. Human endocardial atrial recordings of AFib, sinus rhythm, atrial flutter, and supraventricular tachycardia were collected, and the direction of each activation was calculated using methods previously described. Each recording was divided into segments containing 100 activations, and the spatial precision for each segment was calculated, The spatial precision for all segments of AFib was ⩽0.85, whereas the spatial precision for regular rhythms was 20.91 in all but 4 of 138 instances, The results indicate that spatial precision of local activation direction is a useful discriminator of AFib