Doppler Ultrasound of the Fetal Descending Aorta: An Objective Tool to Assess Placental Blood Flow Resistance in Pregnancies With Discordant Umbilical Arteries

Lindsay S Cahill; Grace V Mercer; Dakshita Jagota; Anjana Ravi Chandran; Natasha Milligan; Shiri Shinar; Clare L Whitehead; Sebastian R Hobson; Lena Serghides; W Tony Parks; Christopher K Macgowan; John C Kingdom; John G Sled; Ahmet A Baschat

doi:10.1002/jum.15773

Doppler Ultrasound of the Fetal Descending Aorta: An Objective Tool to Assess Placental Blood Flow Resistance in Pregnancies With Discordant Umbilical Arteries

J Ultrasound Med. 2022 Apr;41(4):899-905. doi: 10.1002/jum.15773. Epub 2021 Jul 6.

Authors

Lindsay S Cahill¹, Grace V Mercer¹, Dakshita Jagota¹, Anjana Ravi Chandran², Natasha Milligan³, Shiri Shinar², Clare L Whitehead⁴, Sebastian R Hobson², Lena Serghides^{5

6

7}, W Tony Parks^{8

9}, Christopher K Macgowan^{10

11}, John C Kingdom^{2

12}, John G Sled^{10

11

12

13}, Ahmet A Baschat¹⁴

Affiliations

¹ Department of Chemistry, Memorial University of Newfoundland, St John's, Newfoundland and Labrador, Canada.
² Mount Sinai Hospital, Toronto, Ontario, Canada.
³ Division of Cardiology, Department of Paediatrics, The Hospital for Sick Children, Toronto, Ontario, Canada.
⁴ Pregnancy Research Centre, Department of Obstetrics and Gynaecology, Royal Women's Hospital, Parkville, Australia.
⁵ Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada.
⁶ Department of Immunology and Institute of Medical Sciences, University of Toronto, Toronto, Ontario, Canada.
⁷ Women's College Research Institute, Women's College Hospital, Toronto, Ontario, Canada.
⁸ Department of Pathology, Mount Sinai Hospital, Toronto, Ontario, Canada.
⁹ Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada.
¹⁰ Translational Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada.
¹¹ Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada.
¹² Department of Obstetrics and Gynecology, University of Toronto, Toronto, Ontario, Canada.
¹³ Mouse Imaging Centre, The Hospital for Sick Children, Toronto, Ontario, Canada.
¹⁴ Centre for Fetal Therapy, Johns Hopkins Medicine, Baltimore, Maryland, USA.

Abstract

Objectives: To determine the relationship between blood flow in the fetal descending aorta and discordant umbilical arteries (UAs).

Methods: Pulsed wave Doppler of both UAs and the descending aorta was performed at 4-weekly intervals between 14 and 40 weeks of gestation in 209 pregnant women. In datasets with discordant UAs, a linear mixed effects model was used to determine the categorical relationship between the UA pulsatility index (PI) (high, low and average) and the descending aorta PI.

Results: Of the 209 cases, 81 had a discordance of greater than 25% in UA PI during one of their visits. There were no differences in birth outcomes between the groups with concordant and discordant UA PIs. In the cases with discordant UA PIs, the descending aorta PI was most strongly associated with both the average UA PI (P = .008), and with the UA with the lower PI (P = .008).

Conclusions: The relationship between blood flow in the descending aorta and UAs is consistent with the law for combining resistances in parallel. Measurements of the descending aorta PI, particularly in a scenario with discordant UAs, may inform the stability of the feto-placental circulation where discordant UA PIs are found.

Keywords: Doppler ultrasound; descending aorta; discordant umbilical arteries; placenta; pulsatility index.

MeSH terms

Aorta, Thoracic / diagnostic imaging
Blood Flow Velocity
Female
Gestational Age
Humans
Placenta / diagnostic imaging
Placental Circulation*
Pregnancy
Pulsatile Flow
Ultrasonography, Doppler
Ultrasonography, Doppler, Pulsed
Ultrasonography, Prenatal
Umbilical Arteries* / diagnostic imaging

Abstract

MeSH terms

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