[Disorders of sinus-node function: diagnostic and clinical features (author's transl)].

Diagnostic right atrial stimulation was performed before and after atropine (1 mg i. v.) in 28 patients with or without ECG evidence of sinoatrial disease. Sinus-node recovery time was measured after rapid pacing had been stopped. Sinoatrial conduction time was calculated by premature atrial stimulation technique. Results are given for a control group of ten subjects with normal sinus-node function and 18 patients with sinoatrial disease. Using reaction of the pacemaker to single or multiple ectopic beats, it was found that sinus-node recovery time is determined not only by impulse generation but also sinoatrial conduction properties. The results indicate that, in a given patient, sinoatrial disease may be due to impairment of automaticity or sinoatrial conduction or a combination of both. Both stimulation procedures are of diagnostic value in patients who may require a pacemaker implantation.