An Approach to the Examination of the Fetal Congenitally Malformed Heart at Autopsy

Complex congenital heart and lung defects as a cause of hydrops fetalis in French bulldogs -micro-CT with contrast study

Limited data are available on the causes of hydrops fetalis in dogs. Congenital heart defects may be an important contributing factor. Standard autopsy often fails to provide a comprehensive and accurate diagnosis on very small hearts. This study was carried out on five French bulldog puppies all presenting with advanced hydrops fetalis and four diagnosed with pulmonary hypoplasia at autopsy. The body weight of the dogs ranged from 142 to 687 g and the heart with lungs weighed from 4.5 to 23.6 g. The hearts and pulmonary vessels were filled with barium contrast, and micro-CT scans of the physiologically connected heart and lungs were performed. In all five puppies, we confirmed congenital heart defects including: Puppy #1. Perimembranous ventricular septal defect and aortic dextroposition; Puppy #2. Interrupted aortic arch with aortic valve dysplasia and aortic stenosis; Puppy #3. Tricuspid valve dysplasia and bicuspid pulmonary trunk valve; Puppy #4. Aortic stenosis and ventricular septal defect; Puppy #5. Tricuspid valve dysplasia. Additionally, four puppies had pulmonary vascular hypoplasia. Contrast-enhanced micro-CT can provide highly accurate diagnosis of complex congenital heart and lung defects. Examination of the heart in conjunction with the lungs appears to be a rational approach in animals with hydrops fetalis.

Confirmation of Heart Malformations in Fetuses in the First Trimester Using Three-Dimensional Histologic Autopsy

BACKGROUND

We aimed to evaluate the usefulness of three-dimensional (3D) reconstruction of histology slides to confirm congenital heart disease (CHD) detected by first-trimester fetal cardiac ultrasonography. Conventional autopsy is hindered by the small size of the first-trimester fetal heart, and current CHD confirmation studies employ the use of highly specialized and expensive methods.

TECHNIQUE

An extended first-trimester ultrasound examination protocol was used to diagnose fetal heart anomalies. Medical termination of pregnancies was followed by fetal heart extraction. The specimens were sliced, and the histology slides were stained and scanned. The resulting images were processed, and volume rendering was performed using 3D reconstruction software. The volumes were analyzed by a multidisciplinary team of maternal-fetal medicine subspecialists and pathologists and compared with ultrasound examination findings.

EXPERIENCE

Six fetuses with heart malformations were evaluated using histologic 3D imaging: two with hypoplastic left heart syndrome, two with atrioventricular septal defects, one with an isolated ventricular septal defect, and one with transposition of the great arteries. The technique allowed us to confirm ultrasound-detected anomalies and also identified additional malformations.

CONCLUSION

After pregnancy termination or loss, histologic 3D imaging can be used to confirm the presence of fetal cardiac malformations detected during first-trimester ultrasound examination. Additionally, this technique has the potential to refine the diagnosis for counseling regarding recurrence risk and retains the advantages of standard histology.

First Trimester Prenatal Diagnosis of a Conotruncal Anomaly Using Spatiotemporal Image Correlation Imaging Confirmed by Conventional Autopsy

BackgroundFetal echocardiography continues to be the first line investigation for detecting congenital heart diseases (CHD). As accurate and complete diagnosis of complex heart disease is often difficult in the first trimester due to small size of the fetal heart, confirmation/expanded description by fetopsy provides the best information for accurate counseling for future pregnancies. Although non invasive fetal autopsy alternatives have been investigated with favorable results, conventional autopsy remains the gold standard procedure used to confirm the fetal abnormalities. Case report: We describe a conotruncal anomaly diagnosed at 12 weeks gestation using spatiotemporal image. The fetopsy confirmed the diagnosis of Type I Truncus arteriosus. Conclusion: Four-dimensional STIC imaging provides incremental benefits in evaluation of fetal cardiac anomalies, and confirmation by autopsy findings allows further refinement of the diagnosis.

The Evaluation of the Four-Chamber Cardiac Dissection Method of the Fetal Heart as an Alternative to Conventional Inflow–Outflow Dissection in Small Gestational-Age Fetuses

The examination of very small fetal hearts requires special equipment and a specialist that are not available in many general pathology laboratories. Compared to conventional examination, the four-chamber cardiac dissection (4CCD) method can be performed by any pathologist using instruments generally available in pathology services. The aim of this study is to evaluate the efficiency of the 4CCD method in the examination of small fetal hearts using post-mortem magnetic resonance imaging (pm-MRI) at 7T as the standard. Twelve fetuses with gestational ages between 13 and 19 weeks have been included in this study. All fetuses underwent pm-MRI examination prior to pathologic examination. The 4CCD method was used for the cardiac examination in all cases following the same guidelines for cardiac sectioning. The 4CCD was able to identify all cardiac anatomic structures as compared to pm-MRI at 7T, demonstrating a sensibility of 95.8% (95% CI, 94.5–95.8) and specificity of 100% (95% CI, 32.3–100). The overall accuracy in identifying cardiac anatomic structures was 95.8% (95% CI, 93.4–95.8). Additionally, the 4CCD method was able to detect cardiac anomalies with an overall diagnostic accuracy of 91% (95% CI, 85.8–94.2), sensibility of 67.6% (95% CI, 54.5–75.3), and specificity of 97% (95% CI, 93.7–99) as compared to pm-MRI at 7T. The four-chamber view dissection method can be considered as an alternative to the conventional inflow–outflow dissection method in selected cases.

Prenatal diagnosis of double outlet right ventricle with intact ventricular septum in two foetuses

We describe two cases of an unusual variant of double outlet right ventricle with intact ventricular septum diagnosed prenatally and confirmed by foetal autopsy in a case. The first case had mitral valve atresia, slit-like left ventricle, and normally related great arteries. The second case had mitral valve atresia, hypoplastic left ventricle, parallel outflows with an interrupted aortic arch.

Pathologist's role in identifying cardiac defects-a fetal autopsy series

AIMS

Major cardiac abnormalities can lead to miscarriages and is also an important indication of medical termination of pregnancy. The present study aims: (1) To determine the spectrum of cardiac anomalies in fetal autopsies, (2) To correlate the autopsy findings with prenatal imaging studies.

METHODS

Fetal autopsies with cardiac anomalies were retrospectively analyzed over a period of five years. Autopsy diagnoses were correlated with prenatal ultrasound and echocardiogram findings.

RESULTS

Of the 177 fetal autopsies, 40 (22.5%) cases with cardiac defects were identified. Among these cases, 11 (27.5%) showed only cardiac defects and associated extracardiac malformations were seen in 29 cases (72.5%). Septal defects (45%) were the most frequent cardiac defect followed by left ventricular outflow tract obstruction. Agreement with prenatal imaging and autopsy findings was seen in 65% of cases. There was 100% concordance between autopsy and echocardiogram wherever available.

CONCLUSION

Cardiac malformation forms a significant subset of fetal congenital anomalies. Meticulous examination and following sequential segmental analysis during autopsy are essential in identifying complex cardiac and additional extra cardiac defects in the fetuses. Fetal autopsy plays a vital role in confirming and/or refuting the imaging findings and could be the steppingstone in understanding the pathogenesis of cardiac abnormalities.

Undiagnosed Congenital Heart Defects as a Cause of Sudden, Unexpected Death in Children

Despite advances in the diagnosis and treatment of congenital heart defects (CHDs), these defects are still an important cause of sudden, unexpected death in young children. This retrospective study identified 64 cases of CHDs presenting as a cause of sudden, unexpected death in a busy, urban Medical Examiner's Office pediatric population between 2006 and 2016. The majority of cases (52 of 64, 81%) were infants. Interestingly, 52% of cases were undiagnosed prior to autopsy. Ventricular septal defects and atrioventricular septal defects were the most common simple (14%) and complex (17%) malformations observed, respectively. In many cases, there were coexistent simple and/or complex defects. Most of the cases diagnosed with CHD prior to autopsy (48%) had undergone some type of surgical repair. This study highlights the importance of considering undiagnosed CHDs as a cause of sudden, unexpected death, particularly in young children.