- Oral presentation
- Open Access
Combined ventricular output and oxygen delivery are reduced while oxygen extraction fraction is increased in fetuses with Ebstein's Anomaly by MRI
https://doi.org/10.1186/1532-429X-18-S1-O71
© Zhu et al. 2016
- Published: 27 January 2016
Keywords
- Lung Volume
- Oxygen Delivery
- Extraction Fraction
- Brain Weight
- Fetal Weight
Background
Ebstein's anomaly (EA) has variable prognosis. New MRI technology allowing the measurement of vessel blood flow and oxygen content could provide additional prognostic information in the setting of fetal EA.
Methods
We measured fetal weight, brain weight and lung volume in normal and EA fetuses using MRI. Blood flow and T2 in the major fetal vessels were measured using our previously published technique. Fetal oxygen delivery (DO2), consumption (VO2) and extraction fraction (OEF) were calculated using estimated fetal hemoglobin concentration.
Results
MRI measured flow and T2 in major fetal vessels in normal and Ebstein's anomaly fetuses.
CVO | UV | AAo | SVC | DAo | |
---|---|---|---|---|---|
Normal mean flow (ml/min/kg) | 451 ± 56 | 129 ± 29 | 205 ± 47 | 132 ± 31 | 248 ± 45 |
Ebstein's mean flow (ml/min/kg) | 233 ± 45 | 83 ± 17 | 219 ± 40 | 93 ± 32 | 135 ± 33 |
P value | < 0.0001* | < 0.0001* | 0.4 | 0.01* | < 0.0001* |
Normal mean T2 (ms) | 192 ± 34 | 119 ± 23 | 84 ± 13 | 99 ± 17 | |
Ebstein's mean T2 (ms) | 196 ± 26 | 90 ± 15 | 74 ± 8 | 84 ± 22 | |
P value | 0.8 | 0.0005* | 0.01* | 0.3 |
Oxygen consumption, oxygen delivery and oxygen extraction fraction, fetal weight Z score, fetal brain weight Z score and lung volume in normal and Ebstein's anomaly fetuses.
VO2 (ml/min/kg) | DO2 (ml/min/kg) | OEF | Fetal weight Z score | Brain weight Z score | Lung volume | |
---|---|---|---|---|---|---|
Normal | 7.0 ± 1.9 | 20.1 ± 5.1 | 0.35 ± 0.07 | 0.2 ± 0.6 | 0.1 ± 0.9 | 64 ± 24 |
Ebstein | 6.3 ± 1.3 | 13.4 ± 2.5 | 0.47 ± 0.09 | -0.3 ± 0.5 | -1.3 ± 0.7 | 55 ± 17 |
P value | 0.3 | 0.008* | 0.01* | 0.03* | 0.0003* | 0.3 |
Conclusions
MRI revealed a ~50% reduction in CVO in EA fetuses compared to normal fetuses, which is greater than any other type of CHD. While EA subjects had similar placental function (indicated by similar UV T2), lower CVO resulted in reduced UV flow, therefore decreased DO2. EA fetuses had increased OEF compensating for the reduced DO2, but body and brain development were still reduced. In addition, MRI-based lung volume measurements, UV flow and VO2 maybe associated with postnatal outcome in EA fetuses. Therefore, with more experience, the MRI technique may provide useful prognostic information in Ebstein's anomaly pregnancies.
Authors’ Affiliations
Copyright
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.