Fetal Pulmonary Artery Doppler Research Articles

427 Prenatal prediction of the fetal to neonatal cardiovascular transition

We sought to evaluate changes in the fetal pulmonary artery Doppler following maternal hyperoxygenation during the third trimester of pregnancy and correlate those findings with neonatal echocardiograph indices. Forty-six women with a singleton pregnancy ≥31weeks’ gestational age(GA) were prospectively recruited. Pulsatility index(PI),Resistance index(RI), acceleration time(AT) and ejection time(ET) were measured in the distal fetal pulmonary artery (PA). Doppler measurements were taken at baseline and following maternal hyperoxygenation(MH) for 10minutes.Reactivity to MH was considered where a decrease in PAPI was ≥10% from the baseline. Within 24hours of life a neonatal functional echocardiogram was performed to assess right ventricular systolic pressures,PAAT,ejection fraction(EF) and left ventricular cardiac output(LVCO). The median GA was 35weeks. There was a decrease in fetal PAPI and PARI and an increase in PAAT leading to an increase in AT:ET following MH (Table 1).Fetuses that responded to MH had an increased LVCO and EF. These findings were not dependent on LV size or mitral valve (MV) annular diameter but were related to an increased MV inflow.The PA reactivity was not associated with maternal age, BMI or GA at the time of MH (Table 2).The effect of MH on neonatal LVCO and EF was not dependent on mode of delivery or GA at delivery but on the prenatal response to MH. Maternal hyperoxygenation in the third trimester is associated with significant changes in fetal PA Doppler waveforms.An increased LVCO and EF in the neonates who responded to MH,suggests that MH may prove to be a more reliable predictor of postnatal cardio-pulmonary dysfunction compared to the prenatal evaluation of anatomic structures alone. The response to MH predicted neonatal LVCO suggesting that there is a cohort of infants who may be identified by MH,that may have an increased vulnerability to deal with neonatal illness, due to a limited ability to optimise LV preload. This warrants further exploration to establish the ability of MH to predict the neonatal cardiovascular transition.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Prenatal prediction of neonatal haemodynamic adaptation after maternal hyperoxygenation

The reactivity of the pulmonary vascular bed to the administration of oxygen is well established in the post-natal circulation. The vasoreactivity demonstrated by the fetal pulmonary artery Doppler waveform in response to maternal hyperoxia has been investigated. We sought to investigate the relationship between the reactivity of the fetal pulmonary arteries to hyperoxia and subsequent neonatal cardiac function in the early newborn period.MethodsThis explorative study with convenience sampling measured pulsatility index (PI), resistance index (RI), acceleration time (AT), and ejection time (ET) from the fetal distal branch pulmonary artery (PA) at baseline and following maternal hyperoxygenation (MH). Oxygen was administered for 10 min at a rate of 12 L/min via a partial non-rebreather mask. A neonatal functional echocardiogram was performed within the first 24 h of life to assess ejection fraction (EF), left ventricular output (LVO), and neonatal pulmonary artery AT (nPAAT). This study was conducted in the Rotunda Hospital, Dublin, Ireland.ResultsForty-six women with a singleton pregnancy greater than or equal to 31 weeks’ gestational age were prospectively recruited to the study. The median gestational age was 35 weeks. There was a decrease in fetal PAPI and PARI following MH and an increase in fetal PAAT, leading to an increase in PA AT:ET. Fetuses that responded to hyperoxygenation were more likely to have a higher LVO (135 ± 25 mL/kg/min vs 111 ± 21 mL/kg/min, p < 0.01) and EF (54 ± 9% vs 47 ± 7%,p = 0.03) in the early newborn period than those that did not respond to MH prenatally. These findings were not dependent on left ventricular size or mitral valve (MV) annular diameter but were related to an increased MV inflow. There was no difference in nPAAT.ConclusionThese findings indicate a reduction in fetal pulmonary vascular resistance (PVR) and an increase in pulmonary blood flow and left atrial return following MH. The fetal response to hyperoxia reflected an optimal adaptation to postnatal life with rapid reduction in PVR increasing measured cardiac output.

Quantitative Ultrasound Texture Analysis of Fetal Lung Versus Fetal Pulmonary Artery Doppler as a Predictor of Neonatal Respiratory Distress Syndrome (RDS)

Purpose: To evaluate the role of fetal pulmonary artery Doppler indices and quantitative ultrasound texture analysis of the fetal lung (quantus FLM) in prediction of neonatal respiratory distress syndrome. Method: This Observational prospective cross sectional study included 40 pregnant women between 28 and 40 weeks gestation. The diagnostic accuracy of MPA Doppler measurements (pulsatility index (PI), resistance index (RI) and acceleration time/ejection time (AT/ET) for diagnosis of neonatal RDS was tested by comparing the Doppler findings with the clinical outcome. Results: Of the 40 eligible fetuses, 9 (22%) developed neonatal RDS There was a significant correlation between the AT/ET and the development of the RDS as the AT/ET was significantly lower in the RDS +ve group (mean 0.27) in comparison to the RDS-ve group (mean 0.34) (P 0.001). While both PI and RI showed no statistically significant difference in between the two groups. A cutoff value of 0.3 for AT/ET predicted the development of RDS (sensitivity: 77.78%, specificity: 83.87%). Quantus FLM predicted the development of neonatal RDS with high sensitivity, specificity, positive predictive value, negative predictive value and accuracy (88.98%, 90.32%, 72.7%, 96.6% and 90%respectively). The area under curve was 0.896. Conclusion: Neonatal RDS can be predicted using the MPA AT/ET and quantitative ultrasound texture analysis of the fetal lung (quantus FLM) with high sensitivity and specificity.

The role of different fetal pulmonary artery Doppler indices in the prediction of neonatal respiratory distress syndrome

The role of different fetal pulmonary artery Doppler indices in the prediction of neonatal respiratory distress syndrome

418: Changes in fetal pulmonary artery doppler indices in response to maternal hyperoxygenation

The reactivity of the pulmonary vascular bed to the administration of oxygen is well established in the post-natal circulation. We sought to evaluate changes in the pulmonary artery doppler following maternal hyperoxygenation in utero, during the third trimester of pregnancy. Forty six women with a singleton gestation greater than or equal to 31 weeks gestational age were prospectively recruited to the study. A fetal echocardiogram was performed on all subjects to exclude congenital heart disease. Pulsatility index (PI), Resistance index (RI), Peak systolic (PSV) and end diastolic velocity (EDV), acceleration time (AT), and ejection time (ET) were taken within the proximal portion of the fetal main pulmonary artery (PA). AT:ET was used to assess pulmonary vascular resistance (PVR). Doppler measurements were taken at baseline and repeated immediately following maternal hyperoxygenation for 10 minutes (O2 100% v/v inhalational gas) at a rate of 12L/min via a partial non-rebreather mask. Doppler waveform measurements were also taken of the umbilical artery (UAD), middle cerebral artery (MCA) and the ductus arteriosus (DA). The median gestational age was 35 [33 – 37] weeks. There was a decrease in fetal PA PI following maternal hyperoxygenation (from 2.37 [2.04 – 2.70] to 2.05 [1.69 – 2.41], p=0.001). The resistance index of the PA decreased from (0.86 [0.81- 0.91] to 0.78 [0.69-0.87]. There was an increase in PA AT (57 [42-71] to 66 [49 – 82] ms, leading to an increase in AT:ET following maternal hyperoxygenation (0.32 to 0.34], p=0.001) (Table 1). There were no significant changes in the resistance indices of the UAD and DA. There was a significant increase in MCA blood flow, but not in MCA resistance indices. Maternal hyperoxygenation offers the opportunity to assess the reactivity of the pulmonary vasculature before birth. Our findings would indicate a reduction in fetal pulmonary vascular resistance with secondary increased fetal pulmonary blood flow. This was not achieved at the expense of ductal constriction. There was evidence of improved MCA peak systolic velocity parameters; this was likely due to the positive impact of improved pulmonary venous return on left ventricular preload. The hyperoxygenation test can inform us of functional rather than anatomical information in relation to the pulmonary arteries and this warrants further exploration in a larger cohort.

Prediction of neonatal respiratory distress syndrome via pulmonary artery Doppler examination

Objective: We aimed with this study to evaluate the role of pulmonary artery acceleration time to ejection time ratio (PATET) in the prediction of respiratory distress syndrome (RDS) in preterm neonates.Materials and methods: In this prospective cohort study, 105 singleton pregnant women with no congenital abnormalities and pregnancy complications who delivered before 37 weeks of gestational age were included. All the patients underwent ultrasound examination to obtain fetal pulmonary artery Doppler. 15 patients were excluded from the study as they did not give birth within 3 days subsequent to ultrasound examination, or inadequate Doppler measurements. After delivery the neonates were grouped according to diagnosis of RDS as RDS + and RDS−.Results: One hundred five women met the inclusion criteria. Regarding the Doppler findings; only the PATET ratio was significantly different between the groups (0.2965 ± 0.042 versus 0.386 ± 0.068 p < .001, Z = −5.206). There was an inverse correlation between the diagnosis of RDS in the neonates and the PATET values, even after adjusted for gestational age estimated fetal weight and fetal gender (r = −0.52 and p = .0017). A cut-off value of 0.327 provided optimal specificity of 77.1%, a sensitivity of 90.9%, a negative predictive value of 95.4%, and a positive predictive value 52.7%.Conclusions: In consideration of these results fetal PATET ratio is a promising noninvasive tool to predict RDS in cases of preterm deliveries.

A non-invasive method to rule out transient tachypnea of the newborn (TTN): fetal pulmonary artery acceleration to ejection time ratio.

To investigate whether fetal pulmonary artery acceleration to ejection time (PATET) ratio can predict or rule out subsequent diagnosis of transient tachypnea of the newborn (TTN). This prospective cohort study included 105 pregnant women in labor, who met the inclusion criteria. Eighteen of these women were removed from the study cohort, because of an inability to acquire sufficient Doppler waveforms and a longer duration of deliveries. According to subsequent diagnosis of TTN in the neonate, the two groups were constituted, TTN+ and TTN-. There were no statistically significant differences between the groups regarding maternal obstetric and demographic features. The neonatal intensive care unit (NICU) submission rate was significantly higher in the TTN+ group (100%, 17%, P<0.0001, respectively). Regarding the fetal pulmonary artery Doppler findings, PATET ratio in the TTN+ group was significantly lower than the TTN- group (0.307 vs. 0.389, P<0.0001, respectively). The PATET ratio and diagnosis of TTN were inversely correlated (r=-0.41, P<0.001), even if adjusted for birth weight, gestational age and fetal gender (r=0.42, P=0.0021). The cut-off value of 0.319 provided 82.7% specificity, 83.3% sensitivity, 96% negative predictive value and 41.6% positive predictive value. Additionally intraobserver ICC for PATET was found to be 0.86. The fetal PATET ratio seems to serve as a promising tool to rule out subsequent diagnosis of TTN.

Transplacental sildenafil rescues lung abnormalities in the rabbit model of diaphragmatic hernia

IntroductionThe management of congenital diaphragmatic hernia (DH) would benefit from an antenatal medical therapy, which addresses both lung hypoplasia and persistent pulmonary hypertension. We aimed at evaluating the pulmonary effects...

Predicting Fetal Lung Maturity Using the Fetal Pulmonary Artery Doppler Wave Acceleration/Ejection Time Ratio

Objective: To determine whether the acceleration/ejection time ratio of the fetal main pulmonary artery Doppler waveform (PATET) can accurately predict the results of fetal lung maturity testing in amniotic fluid. Methods: We prospectively studied pregnant women attending our ultrasound unit for clinically indicated fetal lung maturity testing. An ultrasound examination that included measurement of the PATET was performed before the results of the amniocentesis were reported. The results of the PATET and the surfactant/albumin ratio were compared, and a receiver operating characteristic curve was used to determine the PATET cutoff with the optimal sensitivity and specificity for predicting surfactant/albumin ratio results. p < 0.05 was considered statistically significant. Results: Forty-three patients were included in this study. The receiver operating characteristic curve demonstrated that a PATET cutoff of 0.3149 provided a specificity of 93% (95% CI 77-98%), a sensitivity of 73% (95% CI 48-89%), a negative predictive value of 87% (95% CI 70-95%), and a positive predictive value of 85% (95% CI 58-96%) for predicting immature surfactant/albumin ratio results. Conclusion: The PATET may provide a noninvasive means of determining fetal lung maturity with acceptable levels of sensitivity, specificity, and predictive values.

Acceleration Time-to-Ejection Time Ratio in Fetal Pulmonary Artery Predicts the Development of Neonatal Respiratory Distress Syndrome: A Prospective Cohort Study

This study investigates whether fetal pulmonary artery Doppler waveforms can predict the subsequent development of respiratory distress syndrome (RDS). A prospective cohort study was performed in women with impending preterm birth. Pulsatility index, resistance index, systolic-to-diastolic ratio, peak systolic velocity, and acceleration time-to-ejection time (At/Et) ratio were measured in the main pulmonary artery of fetus just before delivery. Neonates who developed RDS (n = 11) had significantly lower gestational age at birth than those without RDS (n = 31; median: 28.7 [range: 24.7 to 34.9] versus 32.9 [range: 25.7 to 36.0] weeks; p = 0.003); there was no difference in antenatal corticosteroid administration. Pulmonary artery At/Et ratio was significantly higher in fetuses that developed RDS compared with those that did not (median: 0.37 [range: 0.26 to 0.41] versus median: 0.30 [range: 0.21 to 0.44]; p = 0.008). RDS prediction score (=a hundredfold At/Et ratio) is significantly associated with the subsequent development of RDS after controlling for gestational age by logistic regression analysis (odds ratio = 1.31, 95% confidence interval 1.05 to 1.63, p = 0.017). An elevated At/Et ratio in the fetal pulmonary artery is independently associated with the development of RDS in preterm infants. These data suggest that fetal pulmonary artery Doppler velocimetry may provide a reliable noninvasive technique to evaluate fetal lung maturity, similar to the way in which middle cerebral artery Doppler has replaced amniocentesis for the assessment of fetal anemia.

393: A non-invasive method to predict fetal lung maturity using fetal pulmonary artery Doppler wave acceleration/ejection time ratio

393: A non-invasive method to predict fetal lung maturity using fetal pulmonary artery Doppler wave acceleration/ejection time ratio

363: A non-invasive method to predict fetal lung maturity using fetal pulmonary artery Doppler wave acceleration time/ejection time ratio

363: A non-invasive method to predict fetal lung maturity using fetal pulmonary artery Doppler wave acceleration time/ejection time ratio