The effect of oxytocin on atrial and ventricular repolarization parameters of surface 12-lead electrocardiography(ECG)

Abstract

Aim: We were aimed to demonstrate the effect of oxytocin on both ventricular and atria depolarization parameters. Material and Methods: We planned cross-sectional study. The Seventy- five patients, who were their last trimester and nulipar and admitted to hospital for spontaneous labor, were included to this study. A 12-lead ECG was recorded for each woman twice at 12 hour before oxytocin infusion at rest while in the supine position and shortly after from labor and upon cessation of oxytocin infusion. The Tp-e interval was defined as the interval between the peak and end of the T wave, measurements of the Tp-e interval were performed from precordial leads, and the Tp-e/QTc ratio and P wave dispersion, QTc was calculated from these measurements. In total, 280 pregnant women, of whom 98 were of advanced age and 182 were under 35 years of age were included in the study. The risk of arrhythmia was evaluated by calculating the electrocardiographic P-wave duration, QT interval, T peak-to-end interval, and the Tp-e/QT ratio.Go to:Results: There were statistically significant differences in the Tp–e interval and Tp-e/QTc ratio and other parameters before and after oxytocin infusion , the maximum QTc, minimum QTc, and QTc dispersion values, P wave dispersion and other parameters of repolarization were significantly higher after labor compared to the before labor. Although there were no differences in the Tp-e interval and Tp-e/QTc ratio between the groups, the maximum QTc, minimum QTc, and QTc dispersion values were significantly higher in advanced-age pregnancies compared to the control group. In addition, the P dispersion was greater in advanced-age pregnancies. In correlation analysis, the increased dispersion of QTc and P were positively correlated with maternal age. Multiple linear regression analysis showed that QTc dispersion was independently associated with maternal age. Go to: Conclusion: In conclusion, although study population was small and arrhythmic potential of oxytocin was evaluated with surface ECG. The repolarization parameters were increased in women with oxytocin infusion during their labor. To obtain these repolarization parameters are easy and usage of these parameters as a cardiac arrhythmic risk factor are logical.