[Rhythmographic analysis of atrial extrasystole in patients with sick sinus syndrome]

The comparative analysis of 141 electrocardiograms showing premature atrial contraction from 43 patients with the sick sinus syndrome and 19 subjects with normal sinus nodal function revealed new electrocardiographic signs suggesting sinus dysfunction: an increase in the postextrasystolic pause by more than 135% of the preextrasystolic interval; greater full compensatory pause values; extrasystolic appearance of a full compensatory pause with the coupling interval of less than 68% of the presystolic interval; an increase in the sinus cycle followed the postextrasystolic pause by greater than 50 msec. The proposed criteria show a 5.7-fold increase in the informative value of ECG analysis in the diagnosis of the sick sinus syndrome in premature atrial contraction.