Analysis of arrhythmias based on atrial wall motion. Usefulness and feasibility of recording left and right atrial systole by echocardiography.

The usefulness and feasibility of recording atrial wall motion by M-mode echocardiography guided by two-dimensional examination was evaluated in three groups of consecutive patients: 7 with undefined tachyarrhythmias, 25 in sinus rhythm, and 20 with atrial flutter or fibrillation. Atrial systole was recorded in the left and right atrium in 58 and 98% of the patients, respectively (p less than 0.05). Six of the patients with undefined tachyarrhythmias exhibited electrocardiographic atrioventricular dissociation revealed by preceding echocardiography in all. The precise timing of left and right atrial systole could be recorded in patients in sinus rhythm; right atrial contraction preceded left atrial systole by 42 +/- 31 msec (mean +/- SD). Among patients with atrial flutter or fibrillation, one case of dissimilar atrial rhythms was revealed by echocardiography. Thus, recording of atrial wall motion is feasible in the majority of patients and provides information which is otherwise available only by esophagus ECG or by invasive means.