About the mechanism of atrioventricular heart block in healthy women in labor

In the literature, there are separate messages devoted to the study of ECG in healthy women during pregnancy and childbirth. Yu. I. Arkussky (1947), analyzing a large number of ECGs in pregnant women, found the inversion of the T wave. He explained it by changes in the position of the heart in the chest cavity. Copeland and Stern (1958) found Samoilov-Wenckebach periods in 32 of 260093 ECGs taken from healthy pregnant women. The authors suggested that the slowdown in atrioventricular conduction is caused by an increase in the content of 17-hydroxycorticosteroids. However, A.G. Diorditsa (1952), examining the ECG in pregnant women who did not have organic lesions of the heart, indicates only changes in the amplitude of the P and R waves without disturbances at the same time of atrioventricular conduction.