The effect of alcohol and barbiturate on the frequency of atrial and ventricular premature beats during sleep.

Repeated EEG and ECG monitoring during sleep was carried out in two subjects with ischemic heart disease and one presumably healthy control. All three displayed frequent ectopic heart beats. Two had ventricular and the third atrial premature beats. The study had two objectives: (1) to ascertain the distribution of ectopic beats among the stages of sleep; and (2) to ascertain the effect of alcohol and barbiturates on the frequency of premature beats. Both drugs are known to alter the pattern of sleep stages. It was found that neither atrial nor ventricular premature beats favored a particular sleep stage. Neither drug had a consistent effect on their frequency and there was no correlation with heart rate. For the most part premature beats were fewer on the second night of a procedure although a day filled with anxiety appeared to greatly increase the frequency of premature contractions.