: Fetal Aortic Arch Descending Velocity by Systolic Doppler
: This test uses Doppler ultrasound to measure how fast blood flows through the descending part of the fetal aorta during the heart's pumping phase (systole). It helps assess fetal circulation and screen for conditions such as anemia.
[": A Doppler measurement of peak systolic blood velocity in the fetal descending aorta provides information about fetal blood flow and can help identify increased cardiac output or anemia."]
Key facts at a glance
- LOINC
- 11695-4
- Short code
- Fet Aorta descending Vmax sys DOP
- Synonyms
- Fet Aorta descending Vmax sys DOP
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- us-doppler
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
: What This Test Measures
: The test measures the peak systolic velocity — the fastest speed of blood flow during heart contraction — in the descending portion of the fetal aorta. The measurement is obtained non-invasively using Doppler ultrasound, typically through the mother's abdomen.
: Why the Test Is Performed
: Doctors may order this measurement when there is concern about fetal well-being, growth, or possible fetal anemia. Changes in blood flow velocity can reflect how hard the fetal heart is working to circulate blood and can support further evaluation when combined with other findings.
: How the Procedure Works
: You lie down while a sonographer places an ultrasound probe on your abdomen. Doppler technology detects the movement of blood, and the analyzer calculates the peak velocity from the waveform. The test is painless and usually takes only part of a routine ultrasound session.
: What the Results Can Mean
: Higher-than-expected peak systolic velocity in the fetal aorta may suggest increased cardiac output or anemia, while lower values may relate to reduced flow. Because normal values change with gestational age, results are interpreted against gestational-age standards rather than a single fixed number.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
: Peak systolic velocity in the fetal descending aorta is used as part of a broader assessment of fetal hemodynamics. It can be a useful adjunct when evaluating suspected fetal anemia or cardiac strain, but it is interpretively dependent on gestational age, measurement technique, and clinical context, so it is generally combined with other ultrasound and clinical findings.
Short name
: Fetal Descending Aorta Peak Systolic Velocity
Frequently asked questions
: Is this test painful or risky for the baby?
: Does a high velocity always mean the baby has anemia?
: How should I prepare for the test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
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Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy