Fetal pericardial fluid: a normal finding of the second half of gestation

Embryonic and fetal tiny pericardial fluid collections at less than 12 weeks of gestation

OBJECTIVES

To describe embryonic and fetal tiny pericardial fluid collections (PFCs) using transvaginal sonography and HDlive Silhouette at less than 12 weeks of gestation.

METHODS

During an 8-month period from November 2021 to June 2022, one-hundred and thirty transvaginal scans were performed for first-trimester dating, and eleven tiny PFCs of the embryo or fetus were identified at 8+4 - 11+3 weeks of gestation (three at 8, six at 9, and two at 11 weeks). HDlive Silhouette features of PFC were evaluated. Their clinical characteristics and outcomes were also investigated.

RESULTS

The incidence of tiny PFCs was 8.5 % at less than 12 weeks of gestation. The mean gestational age at the initial examination was 9.5 weeks (SD: ± 0.9). The mean crown-rump length was 25.0 mm (SD: ± 8.5). The mean PFC dimension was 0.8 mm (range: 0.5-1.3, SD: ± 0.2). Pleural effusion was associated with 3 out of 11 PFCs (27.2 %). Ascites was noted in 2 cases (18.2 %). Skin edema was identified in only in 1 case (0.09 %). There was no arrhythmia. Tiny PFC could also be depicted using HDlive Silhouette. First-trimester fetal ultrasound scans at 11 - 13+6 weeks showed no abnormal findings. PFCs resolved until 13 weeks of gestation (Mean: 12 weeks, SD: ± 1.2). All PFC pregnancies resulted in healthy neonates.

CONCLUSIONS

The incidence of tiny PFCs was relatively high in early pregnancy. HDlive Silhouette can depict tiny PFCs of the embryo. Tiny PFCs in early gestation are transient, benign findings in utero.

Ultrasound Features of Fetal Anemia Lessons From Hemoglobin Bart Disease

Insights gained from this review are as follows: (1) Ultrasound is highly effective in early detection of fetal hemoglobin (Hb) Bart disease. (2) The most sensitive parameters in predicting Hb Bart anemia appear to be the cardiac diameter-to-thoracic diameter ratio, middle cerebral artery peak systolic velocity, and placental thickness. (3) Several other ultrasound markers are helpful in increasing specificity, such as hepatosplenomegaly. (4) Hydrops fetalis is not a consequence of heart failure but rather of hypervolemia and high vascular permeability of fetuses, whereas heart failure is a very late consequence of a long-standing overworked heart. (5) Management guidelines for fetuses at risk of Hb Bart disease are proposed.

Fetal Pericardiocentesis

Fetal pericardiocentesis is a safe and effective procedure that is used to drain pericardial effusion in selected fetuses. The aim of the procedure is to reduce the risk of pulmonary hypoplasia, the development of cardiac tamponade and fetal hydrops, and in some cases to allow fetal lung maturity, improving fetal extraction with a better haemodynamic and respiratory condition. In this review, we discuss the indications, technical procedure, and the outcomes of the fetal pericardiocentesis reported in the literature.

Doppler velocimetry of fetal pericardial fluid

OBJECTIVE

To investigate the flow of normal fetal pericardial fluid (PF) with increasing gestational age using Doppler velocimetry.

METHOD

Ninety-five fetuses between 18 and 37 weeks of gestation with PF within the normal range were studied. PF was measured in 4-chamber view using M-mode or real-time ultrasound. Color Doppler was used to display and guide the pulse wave assessment of PF flow. PF waveforms as well as systolic and diastolic velocities were recorded and correlated with gestational age.

RESULTS

PF was detected in all of the fetuses. The mean thickness of the PF rim was 0.95+/-0.45 mm. PF flowed toward the cardiac apex during systole and toward the atrium during diastole. PF waveforms showed bidirectional flow in all fetuses. The flow velocity PF was positively correlated with gestational age in both systole and diastole.

CONCLUSION

Flow velocity of fetal PF increases linearly in both systole and diastole with gestational age. This might indirectly indicate a maturational change in myocardial performance as myocardial velocity is increased.

A review of findings in fetal cardiac section drawings, part 1: The 4-chamber view

OBJECTIVES

The goal of this presentation is to review some of the common and rare fetal heart abnormalities and to provide an easy approach to these findings with schematic drawings.

METHODS

Over the past 10 years, we collected cases in which the common views of the heart were abnormal and the differential diagnoses that existed for each. The presentation shows the normal sonographic sections and then variations of these sections and the associated anomalies. We used illustrative drawings to present these findings, enabling us to point out the main sonographic features of abnormalities of the heart.

RESULTS

The work reviews 17 fetal heart abnormalities in schematic drawings.

CONCLUSIONS

This short review highlights several of the anomalies that can be recognized on the common sonographic views. The drawings tend to simplify the findings but serve as a basis for those doing fetal echocardiography when they encounter an unusual finding.

Characteristics and outcomes of fetuses with pericardial effusions

Little is known about the characteristics and outcomes of fetuses with pericardial effusions (PEs); therefore, this study sought to identify factors associated with fetal PEs and the natural histories and outcomes of fetuses with PEs. Large PEs are associated with a greater likelihood of structural heart disease, impaired cardiac function, and chromosomal abnormalities, and PEs with hydrops or extracardiac malformations are associated with death. Most fetal PEs resolve, and fetuses with isolated PEs have a very good prognosis.

Sonographic methods to detect fetal anemia in red blood cell alloimmunization

Published reports, case studies, and articles from the English language regarding ultrasonographic detection of fetal anemia in red blood cell alloimmunization were obtained from a MEDLINE search from 1966 to November 1999 using the keywords Rh disease, hemolytic disease of the newborn, ultrasound, and Doppler flow studies and combinations thereof. All articles were cross-referenced. Ultrasound techniques including early findings associated with immune hydrops fetalis, multiple morphologic ultrasound markers, and Doppler flow studies that have been used to detect fetal anemia are reviewed and critically evaluated. Noninvasive sonographic techniques may reduce the number of invasive procedures that traditionally are used to follow fetuses at risk for anemia and decrease the associated risks from these procedures.

Borderline findings in fetal cardiac sonography

Borderline or equivocal sonographic findings in the fetal heart are occasionally encountered. Echogenic foci in the ventricles, small pericardial effusions, and mild discrepancy in ventricular size are three such problematic findings. The significance of each of these findings, as currently understood, will be discussed in this article.

The fetal heart: a practical sonographic approach

Structural abnormalities of the heart are a fairly common problem, affecting more than 8 of 1,000 newborns annually in the United States. Therefore, sonographic detection of these anomalies in utero is important. It is possible to detect a high percentage of fetal cardiac anomalies through proper sonographic examination using three central views of the heart: (1) the four-chamber view; (2) the aortic outflow tract view; and (3) the pulmonary output tract view. Although average sonologists may not be able to provide a precise diagnosis for a cardiac abnormality, they are able to recognize such abnormalities in a high percentage of cases by using these three views and by answering the following questions: (1) Is the heart in a normal position? (2) Is the heart size normal? (3) Are the ventricles equal in size? (4) Is there a septal defect? (5) Are the atrioventricular valves in a normal position? and (6) Is there any abnormality of the endocardium, myocardium, or pericardium? This article presents a practical approach to the detection of fetal cardiac anomalies using the four-chamber and outflow tract views. Examples of normal anatomy and cardiac pathology are provided as well as a listing of differential diagnoses that should be reviewed when certain abnormalities are visualized.

Fetal pericardial effusion

Forty-four fetuses with pericardial effusions have been identified by ultrasonographic examinations. The clinical histories and courses of these patients were reviewed. At least eight different clinical features accompanied and were probably responsible for the pericardial effusions. The most common cause of a fetal pericardial effusion was heart failure (13 fetuses). Fetal renal cystic dysplasia with oligohydramnios and other anomalies was present in six fetuses. Four of this group had microscopic evidence of pericarditis on postmortem examination. Fetal pericardial effusions are always a manifestation of another disease process often presenting as fetal hydrops. Some pericardial effusions are transient. The etiologic origin of fetal pericardial effusions differs from that in the child or adult.

The significance and importance of prenatal diagnosis of fetal cardiac malformations by Doppler echocardiography

Pulsed Doppler echocardiography is an excellent technique for cardiac diagnosis and assessment of cardiac performance in combination with M-mode and two-dimensional echocardiography. Its exact role in fetal cardiac diagnosis has not been established. We examined 67 high-risk fetuses for cardiac malformations and found cardiac abnormalities or malfunction in 15. In four fetuses pulsed Doppler echocardiography played a primary or a definitive diagnostic role: One fetus had a complete atrioventricular canal, another lacked the pulmonary valve, the third had transposition of the great vessels without ventricular septal defect, and the fourth had high cardiac output failure caused by placental chorioangioma. Pulsed Doppler echocardiography is an integral part of the ultrasonic cardiac examination in high-risk fetuses and should be used in combination with two-dimensional and M-mode echocardiography. It has an important place in the diagnosis of high-risk fetuses and may have a primary role in the diagnosis of fetuses when ultrasound resolution is poor, where cardiac circulatory hemodynamics are essential for diagnosis, and in complicated cardiac malformations in which a comprehensive and accurate diagnosis can be achieved only with pulsed Doppler echocardiography.