Related Experiment Videos
Reduction of right atrial peak systolic velocity in growth-restricted discordant twins
I Forouzan1, E Graham, M A Morgan
1Department of Obstetrics and Gynecology, University of Pennsylvania Medical Center, Philadelphia, USA.
Objective:
The objective of this study was to measure blood flow velocity changes through the tricuspid valve in intrauterine growth-restricted twins.
Study Design:
Discordant twins were evaluated by measurement of tricuspid valve flow velocities. Twin pairs with one intrauterine growth-restricted fetus caused by uteroplacental insufficiency and one appropriately grown fetus were included in the analysis. Fetuses with chromosomal or structural abnormalities and confirmed twin-twin transfusion syndrome were excluded. Eighteen pairs met these criteria. Student's t test was used for comparison of flow velocities.
Results:
Peak ventricular diastolic flow velocities through the tricuspid valve in the twin with intrauterine growth restriction and the appropriately grown twin were 35.8 +/- 4.43 cm/sec and 34.0 +/- 6.7 cm/sec, respectively (p = 0.35). The atrial peak systolic flow velocity values were 42.1 +/- 1.2 and 50.3 +/- 1.2, respectively (p = 0.049).
Conclusions:
The velocity of blood flow through the tricuspid valve during atrial systole is lower in growth-restricted twins than in appropriately grown cotwins when growth restriction is caused by uteroplacental insufficiency. Its potential in differentiating discordancy from the other causes remains to be explored.