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.

Abruptio placentae in the baboon (Papio spp.)

INTRODUCTION

Placental abruption is a serious condition that increases perinatal morbidity and mortality. Clinical prevention and treatment options are limited, especially in human preterm deliveries. Knowledge of the mechanisms that keep the placenta in place during pregnancy is critical for developing strategies for the prevention of abruption. Failure of physiological transformation of spiral arteries has been described as a major contributing factor of the placental abruption development. Baboons (Papio spp.) share striking similarities with humans in regard to placental structure, utero-placental blood flow, and fetal development; however, the mode of trophoblast invasion is shallow in baboons. This fact prompted the hypothesis that the incidence of placental abruption will be increased in baboons compared to humans.

MATERIAL AND METHODS

Baboon placentas were collected between 2002 and 2008. Two independent veterinary pathologists evaluated the slides. A certified physician pathologist performed additional histology.

RESULTS

Placental abruption was diagnosed in 22 baboons among 2423 live births during the study period (0.9% prevalence). The most common clinical presentations were fetal demise and vaginal bleeding. The most common pathological findings were intraplacental hemorrhages with or without hematoma formation (86.4%). Other findings consisted of neutrophil infiltration (50%), decidual necrosis (22.7%), decidual vascular congestion and inflammation, villous congestion and retroplacental hemorrhage/hematoma (each 18.2%). These pathologic findings were the same for term and preterm deliveries.

CONCLUSION

This is the first systematic study of placental abruption in non-human primates, analyzing a large colony of baboons. Despite differences in trophoblast invasion, the clinical features observed in placental abruption affecting baboons resembled those reported in humans. The cluster of placental pathological findings in baboons also agreed with clinical reports, but the prevalence of these findings differed between baboons and humans. We discuss a mechanism of anti-abruption forces that offset shallow trophoblast invasion observed in baboons.