Fetal heart rate influence on the pulsatility index in the middle cerebral artery.
In 1300 Doppler assessments performed on the fetal cerebral arteries, 5 cases of heart rate deceleration were recorded while studying the middle cerebral artery. There were 3 normal fetuses (mean menstrual age +/- standard deviation: 28.6 +/- 2.1 weeks), one growth-retarded fetus (34 weeks, menstrual age) and 1 fetus with red cell alloimmunization (27 weeks, menstrual age). The magnitude of decline in the heart rate during the deceleration ranged from 44 to 93 bpm (67 +/- 18 bpm). Pulsatility index values were calculated on 44 waveforms and correlated with the heart rate. Linear regression analysis showed a statistically significant inverse correlation between the heart rate and the pulsatility index in the middle cerebral artery of 4 fetuses. These results indicate that heart rate will affect the pulsatility index of the middle cerebral artery.
Mari
G
G
Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, Texas.
Moise
K J
KJ
Deter
R L
RL
Carpenter
R J
RJ
Wasserstrum
N
N
D002536:Cerebral Arteries / Q000000981:diagnostic imaging*; D005260:Female; D006340:Heart Rate, Fetal; D006801:Humans; D011247:Pregnancy; D011674:Pulse; D016216:Ultrasonography, Prenatal