Abstract
OBJECTIVES:The objective of this study is to compare the frequency domain parameters of the heart rate variability (HRV) of normal pregnant women with preeclamptic patients.
METHODS:A case-control study was conducted at Omdurman Maternity Hospital and, during the period from June 2015 to December 2016. Medical, obstetrics history and clinical examination were performed to all studied women guided by prearranged questionnaires. Cardiac autonomic modulation (CAM) of the heart was examined in the study based on frequency domain parameters of HRV, namely, very low frequency (LnVLF), low frequency (LnLF), high frequency (LnHF) power spectral density, normalized low frequency (LF Norm) and high frequency (HF Norm) and LnLF/HF ratio. The cases were 60 patients presented with preeclampsia and another 60 healthy pregnant women as controls. Studied groups were matched for important determinants of HRV.
RESULTS:Patients with preeclampsia achieved significantly higher LF Norm and LnLF/HF [P = 0.044 and 0.033, respectively], but lower HF Norm [P = 0.012], compared with healthy pregnant women. Although all other HRV measurements were higher in the patients with preeclampsia compared with the controls, only LnVLF and LnLF reached statistical significance [P = 0.017 and 0.040, respectively]; when mean heart rate was adjusted. The results also showed no significant difference in HRV when women with mild and severe preeclampsia were compared.
CONCLUSION:Preeclampsia associated with increased cardiac sympathetic modulations with some degree of parasympathetic withdrawal. There is an unexpected global increase in HRV parameters in women with preeclampsia. The present study confirmed that the severity of preeclampsia was not related to the changes in cardiac autonomic modulation.