Improvement in fetal pulmonary hypertension and maturity after reversal of ductal constriction: prospective cohort study.

OBJECTIVES: To test the hypotheses that estimated mean pulmonary arterial pressure (MPAP) decreases and pulmonary vascular maturation, assessed by the ratio of pulmonary arterial flow acceleration time to ejection time (AT/ET ratio), increases after reversal of fetal ductus arteriosus constriction by reducing maternal intake of the causal agent (prostaglandin inhibitors, such as polyphenol-rich foods or non-steroidal anti-inflammatory drugs), and that these effects are independent of gestational age, which are inferences not yet demonstrated in the clinical setting. METHODS: This was a prospective cohort study comparing Doppler echocardiographic ductal flow dynamics, MPAP and pulmonary arterial flow AT/ET ratio in third-trimester fetuses (≥ 28 weeks' gestation) with ductus arteriosus constriction, at the time of diagnosis and after 2 weeks of reduced maternal intake of prostaglandin inhibitors either by suspending the use of pharmacological agents with potential for prostaglandin inhibition or by restricting the consumption of polyphenol-rich foods. MPAP was estimated using the Dabestani equation (MPAP = 90 - (0.62 × AT)), and pulmonary vascular maturity was assessed using the AT/ET ratio, according to reported validation studies. Student's t-test was used for comparison of variables at diagnosis with those after reversal of ductal constriction. Change in MPAP and pulmonary AT/ET ratio between the two assessments was compared with the expected change in the same gestational period in normal fetuses based on reference curves of MPAP and pulmonary AT/ET ratio constructed in normal fetuses from healthy pregnant women at 19-37 weeks' gestation, encompassing the same gestational age range as the study group (28-37 weeks). RESULTS: Seventy pregnancies with fetal ductus arteriosus constriction were included in the study. After 2 weeks of reduced maternal intake of prostaglandin inhibitors, normalization of mean systolic (change from 1.86 ± 0.34 m/s at diagnosis to 1.38 ± 0.41 m/s; P < 0.001) and diastolic (change from 0.41 ± 0.11 m/s to 0.21 ± 0.065 m/s; P < 0.001) ductal velocities and of mean pulsatility index (change from 1.99 ± 0.20 to 2.55 ± 0.42; P < 0.001) was demonstrated. MPAP decreased between the assessments (change from 66.7 ± 6.90 mmHg at diagnosis to 54.5 ± 6.70 mmHg after 2 weeks; P < 0.001) and mean pulmonary AT/ET ratio increased (change from 0.20 ± 0.06 to 0.33 ± 0.07; P < 0.001). Change in MPAP between diagnosis and after 2 weeks of reduced maternal intake of prostaglandin inhibitors was -12.2 ± 0.30 mmHg, which was 5.3-times higher than that in 305 normal fetuses over 2 weeks during the same gestational period (-2.3 ± 0.19 mmHg) (P < 0.001), and change in pulmonary AT/ET ratio between the two assessments was 0.13 ± 0.08, which was 8.7-times higher than that in normal fetuses in the same gestational period (0.015 ± 0.08) (P < 0.001). CONCLUSIONS: Resolution of fetal ductal constriction is followed by a fall in MPAP and by an increase in pulmonary vascular maturity, to a significantly greater degree than is observed in normal fetuses in the same gestational-age period. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Case Series: Fetal Pulmonary Vein A-Wave Reversal: An Early Marker of Left-Sided Cardiac Anomalies?

Background Improvements in congenital heart disease (CHD) screening are needed based on the lack of sensitivity of current screening methods and the understanding that the early detection of certain CHDs may improve outcomes. Fetal venous circulation has caught medical attention, and two studies demonstrated that it is feasible to register pulmonary vein flow velocity waveforms (FVWs) during early gestation. Meanwhile, the latter study proposed pulmonary vein A-wave reversal as a marker of cardiac anomaly. Methods We report a series of six consecutive fetuses with confirmed cardiac anomalies that underwent first-trimester screening, including pulmonary vein FVWs, at our center during 2013. CHD was confirmed by late pregnancy echocardiography, and in three cases fetal autopsies were performed. Result/Discussion The ductus venosus (DV) and nuchal translucency (NT) predicted 50% of CHD cases, whereas the combination of markers identified 66.6% of CHD cases. When adding pulmonary vein assessment, the rate of detection rose to 83.3%. Total five of six cases of CHD had reversal of pulmonary vein A-wave during early pregnancy. The sixth case with CHD and nonreversal of A-wave was described as right ventricle hypoplasia with type 1 tricuspid atresia and persistent ductus arteriosus. Conclusion This is the first series reporting pulmonary vein end-diastolic reversal as a CHD screening add-on during early pregnancy. The addition of pulmonary vein FVW assessment to the current CHD screening bundle could increase the rate detection of cardiac anomalies. This pilot study suggests that pulmonary vein end-diastolic flow reversal favors detection of left-sided CHD over the right-sided ones.

Profiling left and right ventricular proportional output during fetal life with a novel systolic index in the aortic isthmus.

OBJECTIVE: Left ventricular ejection causes forward flow in the fetal aortic isthmus while the right ventricle has a retrograde influence. The aim of this study was to create reference values for an isthmic systolic index (ISI) reflecting the changing influence of right and left ventricular performance on Doppler flow velocity waveforms of the aortic isthmus throughout normal pregnancy. METHODS: Doppler recordings of 260 normal fetuses with a gestational age of 18-37 weeks were reviewed. Peak systolic velocity (PSV) and end-systolic velocity (or systolic nadir; Ns) were measured on all aortic isthmus waveforms. An ISI was derived from the ratio Ns/PSV. Left and right ventricular outputs were also calculated. RESULTS: Up to 22-23 weeks' gestation, the mean ISI is stable at around 0.2. At about 28 weeks, a brief end-systolic deceleration wave is observed on the aortic isthmus waveforms, progressing steadily with gestation and causing a fall of ISI towards a mean value of zero between 30 and 31 weeks. This trend continues thereafter and a mean value of -0.4 was observed at the end of pregnancy. An inverse correlation was found between right ventricular output and Ns (r = -0.334, P = 0.001). Simultaneous recordings of the isthmus and the ductus arteriosus Doppler waveforms demonstrated that the primary cause of the end-systolic deceleration and ultimate reversal of flow at the isthmus is the increasingly dominant flow from the right ventricle. CONCLUSION: The transitional changes of the respective right and left ventricular outputs throughout pregnancy are well profiled by the ISI. This index highlights the physiological increase in fetal right ventricle flow preponderance as pregnancy progresses. Alteration of the ISI profile could be expected in clinical conditions associated with unbalanced alteration of the fetal ventricular outputs.

Assessment of pericallosal arteries by color Doppler ultrasonography at 11-14 weeks: an early marker of fetal corpus callosum development in normal fetuses and agenesis in cases with chromosomal anomalies.

OBJECTIVE: The aims of this study were to determine (a) whether the normal pericallosal vascular map can be visualized using color Doppler ultrasonography in normal fetuses in the first trimester of pregnancy and (b) whether an abnormal pericallosal artery (PA) vascular map can be observed in fetuses with corpus callosum agenesis early in pregnancy. METHODS: In 150 consecutive women undergoing a routine ultrasound examination at 11-14 weeks of gestation in our high-risk pregnancy unit as part of screening for chromosomal abnormalities, a mid-sagittal view of the fetal head was obtained to measure nuchal translucency thickness, assess nasal bones in their corresponding two oblique planes and intracranial translucency. In this view and with color Doppler ultrasonography, we evaluated the vascular map of the PA. RESULTS: The vascular map of the PA was observed in 97.02% of cases at the 11- to 14-week evaluation (144/150 fetuses). Two cases with an abnormal PA were identified and confirmed as corpus callosum agenesis in the second trimester, 1 due to trisomy 13 and the other due to triploidy. CONCLUSIONS: The PA can routinely be observed at the first-trimester evaluation with color Doppler ultrasonography using the mid-sagittal view of the fetal head. The presence of an abnormal vascular map of the PA by Doppler ultrasonography at 11-14 weeks raises the suspicion of corpus callosum agenesis.

"Signo del cometa": primer indicio ecográfico del embarazo eutópico / "Comet sing": first echographic evidence of eutopic pregnancy

Objetivo. Demostrar mediante ultrasonografía la presencia de flujo vascular en el área de implantación («signo del cometa») previa a la observación del saco gestacional. Material y método. Se realizó un estudio observacional en ocho pacientes con mala historia reproductiva que acudieron a consulta por amenorrea conocida. Se les sometió a ecografía endovaginal con estudio Power Doppler y determinaciones seriadas de la subunidad B de gonadotropina coriónica (hCG-B) sérica. Resultados. En las ocho pacientes se identificaron el/los vaso(s) en el lugar de implantación utilizando el Power Doppler antes de la visualización del saco gestacional. Los valores de la hCG-B en dicho momento fluctuaron entre 375 UI y 730 UI, siendo la mediana 515 UI. Conclusión. El primer signo ecográfico de embarazo eutópico serían los vasos deciduales en el área de implantación demostrados con el Power Doppler

Objective. To demonstrate by using ultrasound the presence of vascular flow in the area of implantation («comet sign») before the observation of the gestational sac. Material and method. An observational study was made in eight patients with bad reproductive history, who came to consult because of known amenorrhea. Endovaginal ultrasound with Power Doppler and human chorionic gonadotrophin B (hCG-B) subunit in serum were taken. Results. In the eight patients were identified the vessels at the site of implantation using the Power Doppler, before visualization of the gestational sac. Values of hCG-B at those moments fluctuated between 375 UI and 730 UI, median 515 UI. Conclusion. The first echographic sign of eutopic pregnancy would be the decidual vessels at the site of implantation, demonstrated using the Power Doppler

Ondas de flujo doppler en las venas cavas superior e inferior en fetos normales y con crecimiento restringido / Dopppler flow velocity patterns of the superior and inferior venae cavae in normal fetuses and fetal growth retardation

Objetivo. Evaluar el comportamiento de las velocidades de las ondas de flujo de las venas cavas superior e inferior en gestaciones no complicadas y de fetos afectados por crecimiento restringido y someter a comprobación la hipótesis de que en fetos normales las velocidades en la vena cava inferior son más elevadas que las de la vena cava superior, y cuando existen condiciones de hipoperfusión placentofetal con redistribución de flujo sanguíneo dicha condición se invierte.Material y métodos. Estudio de carácter analítico, prospectivo mixto, longitudinal y de sección transversal en el que mediante flujometría doppler se evalúan 250 fetos normales entre las 12 y 41 semanas y 23 fetos con crecimiento restringido con elevada impedancia o ausencia de velocidades diastólicas en la arteria umbilical. Los parámetros evaluados fueron: durante la sístole ventricular el pico de velocidad sistólica máxima (Smáx) y la velocidad al final de la sístole (Smín). Durante la diástole se midieron los picos de velocidades de las ondas E y A. Se aplicaron técnicas estadísticas descriptivas e inferenciales de acuerdo al tipo de diseño.Resultados. Las velocidades de las ondas de flujo de las venas cavas aumentaron conforme progresó el embarazo; para ambos vasos las velocidades mostraron una tendencia ascendente a medida que avanzó la edad gestacional, siendo variable el grado de correlación entre ambas variables.De la comparación entre las velocidades de las venas cavas superior e inferior en el grupo normal podemos inferir que todas ellas difieren de manera estadísticamente significativa, siendo mayores en la vena cava inferior. Las velocidades de ambos vasos fueron significativamente mayores en el grupo comprendido entre 27 y 41 semanas que las observadas entre las 12 y 26 semanas. En los casos de crecimiento fetal restringido las velocidades de las ondas de flujo de la vena cava superior (Smáx, Smín y E) fueron significativamente mayores y las de la onda A significativamente menores que las de la vena cava inferior. Al comparar los valores entre ambos grupos se pudo comprobar que en el de crecimiento fetal restringido las velocidades en la vena cava superior fueron superiores a las del grupo control en sus componentes Smín, E y A, mientras que no existieron diferencias significativas para las Smáx. En la vena cava inferior fueron significativamente menores la Smáx, Smín, la onda A fue significativamente mayor y las velocidades de E no difirieron de manera significativa.Conclusiones. Los resultados obtenidos ponen en evidencia un aumento progresivo de las velocidades de flujo de las venas cava superior e inferior a lo largo de la gestación, que en fetos normales las velocidades de la vena cava inferior son más elevadas que las de la vena cava superior y que ante situaciones de hipoperfusión placentofetal que activen el circuito de redistribución de flujos las velocidades de la vena cava superior son significativamente mayores que las de la vena cava inferior (AU)

Evaluación mediante flujometría Doppler del dueto arterioso, arteria pulmonar y venas pulmonares en gestaciones de segundo y tercer trimestre / Doppler velocimetry assessment of the ductus arteriosus, pulmonary artery and pulmonary veins during the second and third trimester of pregnancy

Introducción. Se obtienen los valores de referencia de las ondas de velocidad de flujo de la arteria pulmonar (AP), dueto arterioso (DA) y de las venas pulmonares, y se somete a comprobación la hipótesis de una redistribución del flujo sanguíneo entre estos sectores vasculares mediante índices de impedancia. Métodos. Estudio de carácter prospectivo y de sección transversal en el que mediante flujometría Doppler se evalúan 400 fetos normales con edades comprendidas entre las 20 y 40 semanas. Los parámetros evaluados fueron: picos de velocidades sistólicos, diastólicas, tiempos de aceleración (TA) y de eyección (TE), los índices de impedancia (TA/TE) de cada arteria y el índice relativo de impedancia entre el DA y la AP (IRIDAP TA/TE).Resultados. Los valores de la impedancia para el DA disminuyeron con el avance de la edad gestacional; evento contrario fue registrado en la AP, cuyos índices de impedancia aumentaron a medida que el embarazo evolucionó. El IRIDAP TA/TE descendió a medida que el embarazo se acercó al término. Durante los movimientos respiratorios fetales se observó que durante la inspiración los picos sistólicos del DA aumentaron, mientras que los picos sistólicos de la AP disminuyeron. Todas las velocidades de las OVF de venas pulmonares aumentaron conforme avanzó el embarazo. Conclusiones. Los resultados obtenidos ponen en evidencia una redistribución de flujo desde el DA hacia el lecho pulmonar a medida que aquél avanza. Los cambios observa dos en los picos de velocidad de flujo en la AP y en el DA durante los movimientos respiratorios fetales revelan un efecto modulador de éstos sobre las OVF. Los datos presentados pueden resultar de valor en la evaluación del desarrollo del lecho vascular pulmonar y de la eficiencia del ventrículo izquierdo (AU)