Objective: QT dispersion is the difference between longest and shortest QT duration which shows the myocardial repolarisation’s regional heterogeneity. The regional conduction delay or changes in conduction way cause action potential delay which results in regional heterogeneity of repolarisation. Ventricular repolarisation homogeneity is inversely related with QT dispersion so longer QT dispersion is resulted in greater ventricular instability. Heterogenity in ventricular repolarisation may cause serious ventricular arrhythmia and sudden death by the re-entry mechanism. Although pregnancy is a physiologic event, the effect of cardiovascular load during pregnancy on myocardial repolarization is unknown. We aimed to investigate QT dispersion of of un-complicated pregnant women in the third trimester.

Material and Methods: Seventy pregnant (mean age 27±3.5 year) and 70 un-pregnant (mean age 30±2.3 year) women were included to study. ECG was obtained from all cases. Corrected QT (QTc) was calculated by using bazzet formula (QT/√R-R). QTc dispersion was obtained by calculating the difference between longest and shortest QTc.

Results: Maximum QTc was 435.20±44.82 msn, Minimum QTc 375.85±36.49 msn and QTcD 57.85±22.61 msn. Maximum QTc 423.24±34.82 msn, minimum QTc 365.85±33.89 msn and QTcD 63.85±22.61 msn, in control group.

Conclusion: There was no significant difference between groups. In conclusion the pregnancy has not a significant effect on QTc dispersion.