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[Clinical analysis of cardiac reserve function and outcome of preeclampsia.]
Yong Shao1, Ying-Hong Zhang, Hong-Bo Qi
1Department of Obstetrics and Gynecology, First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China.
Objective:
To investigate cardiac reserve function and pregnant results of preeclampsia.
Methods:
Pregnant women chosen by randomized table and hospitalized in the department of obstetrics of the first affiliated hospital of Chongqing Medical University were involved in this study from January to December, 2008. Sixty-nine cases of normal pregnant women were divided into 3 groups: normal group 1 (20 cases), normal group 2 (26 cases) and normal group 3 (23 cases). The normal group number 1 to number 3 were paired to gestational hypertension (20 cases), mild preeclampsia (26 cases) and severe preeclampsia (23 cases), respectively. The digital technique of heart sound signal processing was used to measure cardiac reserve function parameters including the heart rate (HR), the ratio of the amplitude of the first heart sound to the second heart sound (S1/S2) and the ratio of diastolic to systolic duration (D/S) of pregnant women. The pregnant results were also recorded.
Results:
(1) The ratio of S1/S2 in the group of severe preeclampsia 4.5 +/- 3.2 was significantly higher than the group of gestational hypertension 2.2 +/- 1.1 and normal group 3 2.2 +/- 1.1 (P < 0.01). The ratio of D/S of the group of severe preeclampsia 1.1 +/- 0.3 was significantly lower than the group of gestational hypertension 1.4 +/- 0.3 and normal group 3 1.4 +/- 0.2 (P < 0.01). (2) All cases of the normal group number 1 to number 3 and the group of gestational hypertension were found the ratio of D/S >/= 1.00, whereas 1 case (1/26, 4%) of the group of mild preeclampsia and 4 cases (4/23, 17%) of the group of severe preeclampsia were found the ratio of D/S < 1.00. (3) The two cases of the pregnant women (including one woman died of cardiac arrest) with S1/S2 > 5.00 and D/S < 1.00, who were in the group of severe preeclampsia, were sent to Intensive Care Unit after delivery. There were 4 cases (4/26, 15%) and 6 cases (6/23, 26%) of 1 minute Apgar score less than 7, 7 cases (7/26, 27%) and 6 cases (6/23, 26%) sent to neonatal Intensive Care Unit, 2 cases (2/26, 8%) and 4 cases (4/23, 17%) of neonatal death in the group of mild preeclampsia and in the group of severe preeclampsia, respectively. All newborns in the normal group number 1 to number 3 and the group of gestational hypertension were normal.
Conclusions:
The cardiac reserve function of a pregnant woman with preeclampsia is decreased with the severity of preeclampsia and the parturient and neonatal results get worse. The digital technique of heart sound signal processing is a safe, harmless, simple and effective tool to measure cardiac reserve function of preeclampsia, and is worthy of widely used clinically.
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