Velocity Time Integral: A Novel Method for Assessing Fetal Anemia.
Ettie PiuraOffra EngelNeta DoctoryNisim ArbibTal Biron-ShentalMichal KovoShmuel ArnonOfer MarkovitchPublished in: Children (Basel, Switzerland) (2023)
The velocity time integral (VTI) is a clinical Doppler ultrasound measurement of blood flow, measured by the area under the wave curve and equivalent to the distance traveled by the blood. This retrospective study assessed the middle cerebral artery (MCA) VTI of fetuses in pregnancies complicated by maternal alloimmunization. Doppler indices of the MCA were retrieved from electronic medical records. Systolic deceleration-diastolic time, systolic acceleration time, VTI, and peak systolic velocity (PSV) were measured at 16-40 weeks gestation. Cases with PSV indicating fetal anemia (cutoff 1.5 MoM) and normal PSV were compared. The study included 255 Doppler ultrasound examinations. Of these, 41 were at 16-24 weeks (group A), 100 were at 25-32 weeks (group B), and 114 were at 33-40 weeks (group C). VTI increased throughout gestation (5.5 cm, 8.6 cm, and 12.1 cm in groups A, B, and C, respectively, p = 0.003). VTI was higher in waveforms calculated to have MCA-PSV ≥ 1.5 MoM compared to those with MCA-PSV < 1.5 MoM (9.1 cm vs. 14.1 cm, respectively, p < 0.001), as was VTI/s (22.04 cm/s vs. 33.75 cm/s, respectively; p < 0.001). The results indicate that the MCA VTI increases significantly among fetuses with suspected anemia, indicating higher perfusion of hemodiluted blood to the brain. This feasible measurement might provide a novel additional marker for the development of fetal anemia.
Keyphrases
- blood flow
- gestational age
- birth weight
- blood pressure
- left ventricular
- chronic kidney disease
- preterm birth
- middle cerebral artery
- heart failure
- iron deficiency
- preterm infants
- multiple sclerosis
- magnetic resonance
- computed tomography
- resting state
- white matter
- pregnancy outcomes
- physical activity
- contrast enhanced
- ejection fraction
- ultrasound guided
- contrast enhanced ultrasound