Intertwin discordance of aldosterone levels in amniotic fluid with placental anastomoses in monochorionic twins: Insight into the pathophysiology of twin-to-twin transfusion syndrome.

INTRODUCTION: Our objective was to investigate the association between the presence of placental anastomoses and intertwin differences in renin-angiotensin-aldosterone activation in monochorionic twins using amniotic fluid aldosterone (AF-ALD) levels. In addition, this study also examined the association between AF-ALD and the ALD levels in the umbilical cord blood (UCB-ALD) in monochorionic twins. MATERIAL AND METHODS: This prospective study included monochorionic diamniotic (MD) twin pregnancies that were not complicated by twin-to-twin transfusion syndrome (TTTS) at delivery. Amniotic fluid and umbilical cord vein blood samples were collected from each twin at delivery, and the ALD levels were measured subsequently. The MD twins were divided into two groups: those with placental anastomoses and those without anastomoses owing to fetoscopic laser surgery. The differences in the AF-ALD levels between the larger and smaller twins were analyzed. RESULTS: The AF-ALD levels showed a strong and significant positive correlation with UCB-ALD levels in 131 MD twins (r = 0.804, p < 0.001). Intertwin differences were examined in 41 and 28 pairs of MD twins with and without placental anastomoses, respectively. The AF-ALD levels in the smaller twins were significantly higher than those in the larger twins among the pairs of MD twins with placental anastomoses (p = 0.003); however, no statistically significant intertwin differences were observed among the twins without placental anastomoses (p > 0.05). CONCLUSIONS: The AF-ALD levels reflect the UCB-ALD levels in MD twins. The presence of placental anastomoses led to intertwin discordance in the ALD levels in MD twins even uncomplicated with TTTS. It was considered that monochorionic twins have this clinical background, and it leads to the development of TTTS.

The iPREFACE score is useful for predicting fetal acidemia: A retrospective cohort study of 113 patients who underwent emergency cesarean section for non-reassuring fetal status during labor.

BACKGROUND: The iPREFACE score may aid in predicting fetal acidemia and neonatal asphyxia in emergency cesarean and vaginal deliveries, which may improve labor management precision in the future. OBJECTIVE: This study aimed to assess the score use of the iPREFACE as an objective indicator of the need for rapid delivery in cases of repeated abnormal waveforms without concurrent indications for immediate medical intervention during labor. STUDY DESIGN: This retrospective cohort study was conducted among term (37+ 0 days to 41+6 days) singleton pregnant women who underwent emergency cesarean delivery owing to a nonreassuring fetal status. The integrated score index to predict fetal acidemia by intrapartum fetal heart rate monitoring-decision of emergency cesarean delivery score, calculated from a 30-minute cardiotocography waveform before the decision to perform emergency cesarean delivery, and the integrated score index to predict fetal acidemia by intrapartum fetal heart rate monitoring-removal of cardiotocography transducer score, calculated from a 30-minute cardiotocography waveform before cardiotocography transducer removal, were employed. The primary outcome was the assessment of the predictive ability of these scores for fetal acidemia, whereas the secondary outcomes were differences in umbilical artery blood gas findings and postnatal outcomes between the 2 groups, divided by the cutoff values of the integrated score index to predict fetal acidemia by intrapartum fetal heart rate monitoring-removal of cardiotocography score. RESULTS: The integrated score index to predict fetal acidemia by intrapartum fetal heart rate monitoring-decision of emergency cesarean delivery and integrated score index to predict fetal acidemia by intrapartum fetal heart rate monitoring-removal of cardiotocography transducer scores demonstrated the capability to predict an umbilical artery blood pH of <7.2. The integrated score index to predict fetal acidemia by intrapartum fetal heart rate monitoring-decision of emergency cesarean delivery and -removal of cardiotocography transducer score, with cutoff values of 37 and 46 points, respectively, exhibited an area under the receiver operating characteristic curve of 0.82 and 0.87, respectively. The integrated score index to predict fetal acidemia by intrapartum fetal heart rate monitoring-removal of cardiotocography transducer group with ≥46 points had higher incidence rates of an umbilical cord artery blood pH of <7.2, <7.1, and <7.0 and neonatal intensive care unit admissions for neonatal asphyxia. CONCLUSION: The integrated score index to predict fetal acidemia by intrapartum fetal heart rate monitoring, derived from cardiotocography during an emergency cesarean delivery, may enable clinicians to predict fetal acidemia in cases of nonreassuring fetal status. Improved prediction of fetal acidemia and facilitation of timely intervention hold promise for enhancing the outcomes of mothers and newborns during childbirth. Prospective studies are warranted to establish precise cutoff values and to validate the clinical application of these scores.

Different expressions of cardiac biomarkers between different types of acquired right ventricular outflow tract abnormality in monochorionic twins.

OBJECTIVE: To investigate the differences in amniotic fluid cardiac biomarkers and clinical features among types of right ventricular outflow tract (RVOT) abnormality in monochorionic (MC) twins. METHOD: This prospective study included MC twins that underwent laser surgery. Recipient or larger twins (group A) and donor or smaller twins (group B) were assessed and divided into those with a normal right ventricular outflow tract (normal RVOT), functional pulmonary atresia (fPA), or pulmonary stenosis (PS). Amniotic fluid levels of NT-proBNP (afNT-proBNP) and cardiac troponin T (afTnT) were examined during surgery. RESULTS: Of 190 fetuses in group A, there were 14 RVOT abnormality cases (including 7 fPA and 7 PS). No group B fetuses showed RVOT abnormality findings. In group A, later and earlier gestational age at surgery were observed in fPA (25.1 ± 2.8 weeks) and PS groups (17.8 ± 0.9 weeks). All survived PS cases demonstrated progressive pulmonary valve obstruction, not observed in fPA groups. AfNT-proBNP were significantly higher in fPA and PS than in the normal RVOT group (p < 0.05). AfTnT was significantly higher in group A with PS than fPA and normal RVOT groups (p < 0.05). CONCLUSION: Among RVOT abnormality types in group A, amniotic fluid cardiac biomarkers were differently expressed, and clinical features were also differentiated. These findings provide insight into the pathophysiological influence on RVOT in MC twins. CLINICAL TRIAL REGISTRATION: This study was registered with the Japanese Clinical Trial Registry "UMIN-CTR" (http://www.umin.ac.jp/ctr/index-j.htm; trial ID numbers UMIN000024486 and 000037702).

Optimal duration of cardiotocography assessment using the iPREFACE score to predict fetal acidemia.

Cardiotocography (CTG) applicability to improve fetal outcomes remains controversial. This study aimed to determine the clinically optimal CTG assessment duration using the integrated score index to predict fetal acidemia by intrapartum fetal heart rate monitoring (iPREFACE score). This single-center, retrospective observational study included 325 normal full-term singleton vaginal deliveries at the Toho University Omori Medical Center, from September 2018 to March 2019. The iPREFACE(10), iPREFACE(30), and iPREFACE(60) scores were calculated at 10, 30, and 60 min immediately before delivery. The primary outcome was fetal acidemia (umbilical artery blood pH < 7.2). The secondary outcome was the correlation between all iPREFACE scores and the umbilical artery blood pH, base excess (BE), and lactate values. Patients without accurate CTG findings or with failure of umbilical artery blood sampling immediately after birth were excluded, leaving 145 patients in the final analysis. Of these, 16, three, and two had umbilical artery blood pH of < 7.2, < 7.1, and < 7.0, respectively. All iPREFACE scores significantly correlated with umbilical artery blood pH, BE, and lactate values. iPREFACE(30) had the highest predictive capacity for fetal acidemia, suggesting that 30 min immediately before delivery may be a useful scoring time in clinical practice.

Association of amniotic fluid natriuretic peptide levels with ductus venosus Doppler flow in recipient twins with twin-to-twin transfusion syndrome : DV flow and NT-proBNP in TTTS recipient twins.

PURPOSE: This study examined the relationships between fetal quantitative Doppler parameters and amniotic fluid N-terminal prohormone brain natriuretic peptide (afNT-proBNP) levels as a biomarker of the increased cardiac load in recipient twins with twin-to-twin transfusion syndrome (TTTS). METHODS: This single-center, prospective study included all monochorionic diamniotic (MD) twin pregnancies that were diagnosed with TTTS and underwent fetoscopic laser surgery. Doppler flow was used to measure the pulsatility index (PI) of the umbilical artery (UA), ductus venosus (DV), and middle cerebral artery (MCA) of each recipient and donor twins. The afNT-proBNP levels of recipient twins were examined at the time of surgery. The Spearman or Pearson correlation coefficients were used to assess the relationships between afNT-proBNP levels and Doppler parameters. RESULTS: A total of 150 MD twin pregnancies were included. The afNT-proBNP levels of the recipient twins showed a stronger correlation with the DV-PI (r = 0.637; P < 0.001) of recipient twins than with the UA-PI and MCA-PI of recipient twins. The Doppler parameters of donor twins were scarcely correlated with the afNT-proBNP levels of the recipient twins. CONCLUSION: A positive correlation between the DV-PI and afNT-proBNP levels of recipient twins with TTTS was observed. The recipient twin with an increased DV-PI is expected to be under a high cardiac load; therefore, DV-PI is a useful parameter for assessing increased NT-proBNP levels consecutively and noninvasively. CLINICAL TRIAL REGISTRATION: This study was registered with Japanese Clinical Trial Registry "UMIN-CTR" ( http://www.umin.ac.jp/ctr/index-j.htm ; trial ID numbers UMIN000024486 and 000037702).