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Fetal Cardiac Function and Venous Circulation - Experiences with Velocity Vector Imaging

Dahlbäck, Charlotte LU (2015) In Lund University, Faculty of Medicine Doctoral Dissertation Series 2015-102.
Abstract
Placental dysfunction resulting in intrauterine growth restriction (IUGR) is a common complication of pregnany

and severe IUGR, with ensuing fetal hypoxia is an important cause of perinatal mortality and morbidity. Doppler

studies of fetal and maternal vessels are routinely used for fetal surveillance and alterations in fetal venous blood

flow has been demonstrated as a late sign of fetal compromise. However, the role of venous blood flow

investigations in decisions on delivery has not been clearly defined and abnormal ductus venosus blood flow has

shown moderate accuracy in predicting adverse perinatal outcome. The mechanisms behind ductus venosus

dilatation in fetal hypoxia, the... (More)
Placental dysfunction resulting in intrauterine growth restriction (IUGR) is a common complication of pregnany

and severe IUGR, with ensuing fetal hypoxia is an important cause of perinatal mortality and morbidity. Doppler

studies of fetal and maternal vessels are routinely used for fetal surveillance and alterations in fetal venous blood

flow has been demonstrated as a late sign of fetal compromise. However, the role of venous blood flow

investigations in decisions on delivery has not been clearly defined and abnormal ductus venosus blood flow has

shown moderate accuracy in predicting adverse perinatal outcome. The mechanisms behind ductus venosus

dilatation in fetal hypoxia, the transmissions of pulses in the fetal venous system and the association between

venous blood flow and cardiac function have also not been completely clarified.

We investigated ductus venosus and umbilical venous blood flow patterns and the association between

alterations in the two vessels and adverse perinatal outcome. Changes in ductus venosus blood flow during

systole occurred more rarely than diastolic changes and were more often associated with adverse periatal

outcome. UV-pulsations seemed to be an independent indicator of fetal compromise, regardless of ductus

venosus pulsatility index for veins (PIV), which was not a reliable indicator of fetal compromise as an isolated

finding.

The heart is a crucial organ for fetal adaptation to placental insufficiency. Studies have indicated cardiac damage

and remodelling during chronic hypoxia and estimations of cardiac function may therefore be useful for fetal

surveillance in IUGR. The best suited parameters, however, remain to be established. Methods that analyze

cardiac deformation have recently been developed and have shown promise. Using the novel speckle tracking

technique Velocity Vector Imaging, strain, strain rate and velocity of the ventricular and atrial walls were

measured in a cohort of 250 healthy fetuses and compared to results in a group of 38 fetuses with signs of

impaired placental function. Reference ranges were constructed for the control group. Cardiac strain did not

differ between the control and study groups and there was no association between ductus venosus PIV, umbilical

vein pulsations and ventricular or atrial strain, strain rate or velocity. This indicates that during fetal hypoxia,

circulatory redistribution results in preservation of cardiac deformation thereby maintaining cardiac output

intact (Less)
Please use this url to cite or link to this publication:
author
supervisor
opponent
  • Professor Juha, Räsänen, University of Oulu, Deparment of Obestrics and Gynecology
organization
publishing date
type
Thesis
publication status
published
subject
keywords
pregnancy, fetus, strain, speckle tracking, cardiac function, umbilical vein, venous, ductus venosus, Doppler
in
Lund University, Faculty of Medicine Doctoral Dissertation Series
volume
2015-102
pages
66 pages
publisher
Research Unit for Urogynaecology and Reproductive Pharmacology
defense location
Department for Obstetrics and Gynecology, Jan Waldenströms gata 47, Auditorium, 3:rd floor.
defense date
2015-10-02 09:00
ISSN
1652-8220
ISBN
978-91-7619-181-1
language
English
LU publication?
yes
id
d72969fc-cd88-4ee6-8c5c-cba0af071d42 (old id 8055289)
date added to LUP
2015-10-19 12:39:12
date last changed
2016-09-19 08:44:50
@phdthesis{d72969fc-cd88-4ee6-8c5c-cba0af071d42,
  abstract     = {Placental dysfunction resulting in intrauterine growth restriction (IUGR) is a common complication of pregnany<br/><br>
and severe IUGR, with ensuing fetal hypoxia is an important cause of perinatal mortality and morbidity. Doppler<br/><br>
studies of fetal and maternal vessels are routinely used for fetal surveillance and alterations in fetal venous blood<br/><br>
flow has been demonstrated as a late sign of fetal compromise. However, the role of venous blood flow<br/><br>
investigations in decisions on delivery has not been clearly defined and abnormal ductus venosus blood flow has<br/><br>
shown moderate accuracy in predicting adverse perinatal outcome. The mechanisms behind ductus venosus<br/><br>
dilatation in fetal hypoxia, the transmissions of pulses in the fetal venous system and the association between<br/><br>
venous blood flow and cardiac function have also not been completely clarified.<br/><br>
We investigated ductus venosus and umbilical venous blood flow patterns and the association between<br/><br>
alterations in the two vessels and adverse perinatal outcome. Changes in ductus venosus blood flow during<br/><br>
systole occurred more rarely than diastolic changes and were more often associated with adverse periatal<br/><br>
outcome. UV-pulsations seemed to be an independent indicator of fetal compromise, regardless of ductus<br/><br>
venosus pulsatility index for veins (PIV), which was not a reliable indicator of fetal compromise as an isolated<br/><br>
finding.<br/><br>
The heart is a crucial organ for fetal adaptation to placental insufficiency. Studies have indicated cardiac damage<br/><br>
and remodelling during chronic hypoxia and estimations of cardiac function may therefore be useful for fetal<br/><br>
surveillance in IUGR. The best suited parameters, however, remain to be established. Methods that analyze<br/><br>
cardiac deformation have recently been developed and have shown promise. Using the novel speckle tracking<br/><br>
technique Velocity Vector Imaging, strain, strain rate and velocity of the ventricular and atrial walls were<br/><br>
measured in a cohort of 250 healthy fetuses and compared to results in a group of 38 fetuses with signs of<br/><br>
impaired placental function. Reference ranges were constructed for the control group. Cardiac strain did not<br/><br>
differ between the control and study groups and there was no association between ductus venosus PIV, umbilical<br/><br>
vein pulsations and ventricular or atrial strain, strain rate or velocity. This indicates that during fetal hypoxia,<br/><br>
circulatory redistribution results in preservation of cardiac deformation thereby maintaining cardiac output<br/><br>
intact},
  author       = {Dahlbäck, Charlotte},
  isbn         = {978-91-7619-181-1},
  issn         = {1652-8220},
  keyword      = {pregnancy,fetus,strain,speckle tracking,cardiac function,umbilical vein,venous,ductus venosus,Doppler},
  language     = {eng},
  pages        = {66},
  publisher    = {Research Unit for Urogynaecology and Reproductive Pharmacology},
  school       = {Lund University},
  series       = {Lund University, Faculty of Medicine Doctoral Dissertation Series},
  title        = {Fetal Cardiac Function and Venous Circulation - Experiences with Velocity Vector Imaging},
  volume       = {2015-102},
  year         = {2015},
}