[Relationship between the oscillatory contractions and myocardial tonus in patients with heart defects].

Interplay between contraction oscillations and the tone that is seen during rhythmic stimulation was studied in atrial trabeculae of patients with heart diseases. It was disclosed that in 50% of myocardial preparations from patients with rheumatic heart diseases, an increase in the tone (incomplete relaxation) and oscillations appeared at a frequency of 0.2 HZ.