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Published on: June 29, 2013
Dynamics of the septum primum in fetuses with intrauterine growth restriction
Paulo Zielinsky1, Paulo Afonso Beltrame, João Luiz Manica
1Fetal Cardiology Unit, Institute of Cardiology of Rio Grande do Sul, FUC, Porto Alegre, Brazil.
Insights
Septum primum (SP) mobility, measured by excursion index (EI), is reduced in fetuses with intrauterine growth restriction (IUGR) over 30 weeks gestation. This finding correlates with placental insufficiency.
Area of Science:
- Fetal cardiology
- Perinatology
- Obstetrics
Background:
- Intrauterine growth restriction (IUGR) is a significant concern in high-risk pregnancies.
- Assessing fetal well-being often involves evaluating cardiac function and placental health.
Purpose of the Study:
- To investigate if septum primum (SP) linear displacement is reduced in fetuses with IUGR compared to those with appropriate growth for gestational age (AGA).
Main Methods:
- A cross-sectional study compared the excursion index (EI), the ratio of SP displacement to left atrial diameter, in fetuses with IUGR, AGA fetuses of hypertensive mothers, and controls.
- Umbilical artery resistance index (RI) and atrioventricular (AV) valve flow were also assessed.
Main Results:
- Fetuses with IUGR exhibited a significantly lower mean EI compared to both AGA fetuses and controls, irrespective of gestational age.
- In fetuses over 30 weeks gestation, the reduced EI in the IUGR group persisted and showed a significant inverse correlation with umbilical artery RI.
- No correlation was found between EI and AV flow velocities.
Conclusions:
- Reduced SP mobility, indicated by lower EI, is a characteristic finding in fetuses over 30 weeks gestation with IUGR.
- This reduction may reflect altered left ventricular diastolic function and is associated with the severity of placental insufficiency.
Purpose:
To test the hypothesis that the linear displacement of the septum primum (SP) is lower in fetuses with intrauterine growth restriction (IUGR) than in fetuses with appropriate growth for gestational age (AGA).
Methods:
In a cross-sectional study, the ratio between the SP displacement and left atrial diameter (excursion index [EI]) was compared in 27 fetuses with IUGR (group 1), 24 fetuses with AGA of hypertensive mothers (group 2), and 35 controls (group 3). Flow through the atrioventricular (AV) valves and the umbilical artery resistance index (RI) were also compared.
Results:
Irrespective of gestational age, mean EI in group 1 (0.41 +/- 0.07) was significantly lower than in group 2 (0.48 +/- 0.07; p < 0.001) and than in group 3 (0.50 +/- 0.06; p < 0.001), with no significant differences between groups 2 and 3. In fetuses over 30 weeks of gestation of group 1, EI was lower (0.38 +/- 0.05) than in group 2 (0.49 +/- 0.07) and group 3 (0.51 +/- 0.06; p < 0.001). There was significant inverse correlation between EI and RI (r = 0.46; p < 0.01) and no correlation between EI and AV flow velocities.
Conclusions:
SP mobility is reduced in fetuses over 30 weeks with IUGR compared with AGA fetuses. These findings may depend on alterations of left ventricular diastolic function and are correlated to the degree of placental insufficiency.
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