Atrial and ventricular asystole for 19 seconds without syncope. Report of a case.

A 58-year-old male presented with a three-year-long history of short attacks of loss of consciousness. Epilepsy was suspected and phenobarbital and diphenylhydantoin were given, but without effect. Ambulatory ECG monitoring for four days revealed episodes of sinus bradycardia, marked sinus arrhythmia, and episodes of atrial and ventricular standstill. The longest asystolic period, without escape of lower pacemakers, was 20 sec and was recoreded during undisturbed sleep. Another long atrial and ventricular asystolic period with a duration of 19 sec, recorded during daily activity, was accompanied by dizziness but without loss of consciousness. The patient's symptoms were relieved by implantation of a pacemaker.