Electrocardiographic Qrs Axis, Q Wave and T-wave Changes in 2nd and 3rd Trimester of Normal Pregnancy

Abstract

Background: Pregnancy although a physiological phenomena affects all the functions of the maternal body and brings about remarkable changes in the cardiovascular system. The cardiovascular changes and many of the physiological adaptations of normal pregnancy alter the physical findings thus, sometimes misleading the diagnosis of heart disease. Pregnancy also brings about various changes in the electrocardiogram, further confusing with that of heart disease. This study is undertaken to highlight the effect of normal pregnancy on the QRS axis, Q wave and T-wave of the Electrocardiogram and thereby helps us to distinguish it from that of pathological changes. Objectives: To study the effect of normal pregnancy on the QRS axis, Q wave and T-wave in the electrocardiogram and to compare with that of normal non pregnant women. Materials and Methods: Fifty normal pregnant women in 2nd and 3rd trimester each between 20– 35 y of age and 50 normal non pregnant women of the same age group were selected for the study. A 12 lead ECG was recorded by using ECG machine with special emphasis on QRS axis, Q wave and T-wave changes and all the parameters were analysed. Results: The ECG changes observed in our study include, deviation of QRS axis towards left as pregnancy advanced, significant increased incidence of occurrence of prominent Q waves in lead II, III and avF in pregnant group (p < 0.05 ) and, T-wave abnormalities like flat and inverted T-waves in lead III, V1 – V3 were more frequent in pregnant group ( p< 0.05 ) than in non pregnant group. Conclusion: Normal pregnancy brings about various changes in ECG. These changes during pregnancy should be interpretated with caution by the physicians. It is necessary to understand the normal physiological changes which in turn help us in better management of those with cardiac disease.

Keywords

• electrocardiogram
• pregnancy
• qrs axis
• t-wave changes