Objective. To determine the relationship between fetal coronary blood flow (CBF) visualization in intrauterine growth restriction (IUGR), longitudinal changes in arterial and venous flow velocity waveforms and perinatal outcome. Methods. A total of 48 IUGR fetuses (abdominal circumference below the 5th percentile for gestational age) with absent or reversed umbilical artery (UA) end-diastolic velocity (AREDV) were examined longitudinally by echocardiography attempting CBF visualization at each examination. Doppler evaluation of the middle cerebral artery, inferior vena cava (IVC), ductus venosus (DV) and umbilical vein (UV) was performed at each examination. Doppler measurements were correct for gestational age by conversion into Z-scores (Δ-indices). Doppler results and outcome from fetuses in which CBF was visualized (group 1, n = 20) and those in which CBF was never visualized (group 2, n = 28) were compared. Outcome parameters analyzed included Apgar scores, cord arterial blood gases, perinatal mortality, respiratory distress, bronchopulmonary dysplasia, intraventricular hemorrhage, necrotizing enterocolitis and postpartum circulatory failure requiring pressor support. Results. There was no difference in Doppler indices between groups at study entry. CBF visualization coincides with a significant increase of UA-, IVC- and DV Δ-indices. The greatest rate of change was observed for indices in the ductus venosus which occurred in the 24 h preceding CBF visualization. Group 1 fetuses required earlier delivery (median 27 + 4, vs. median 30 + 0), had lower birth-weight (682 ± 305 g vs. 936 ± 416 g), lower cord pH (7.21 ± 0.1 vs. 7.27 ± 0.06) and cord pO2 (13 ± 4.5 vs. 24.1 ± 13.5 mmHg) compared to group 2 (all values P < 0.05). Mortality was similar (group 1 = 6/20, 30%; group 2 = 6/28, 21.4%). Conclusions. In IUGR, fetuses with AREDV and centralization are at high risk for hypoxemia, acidemia and adverse outcome. CBF visualization coincides with deteriorating venous flows. Operator dependence of CBF visualization and the strong association with abnormal venous flow stresses the importance of venous Doppler surveillance in these fetuses.
- Coronary blood flow
- Fetal growth restriction
ASJC Scopus subject areas
- Radiological and Ultrasound Technology
- Reproductive Medicine
- Radiology Nuclear Medicine and imaging
- Obstetrics and Gynecology