EP09.70: Prenatal diagnosis of fetal cardiac mucocele: a case report

The pregnant woman was 29 years old. Gestation 22+3 weeks, G1P0. Previously healthy. 22+3 weeks of echocardiogram: fetal heart cardiothoracic area ratio was 0.32, a loose medium echo mass was detected in the left atrium, the size was 1.2cm×0.5cm, the boundary was clear, the base was wide, the mass was attached to the mitral annulus, and the activity was large. Diastolic mitral E, a peak existed, systolic mitral regurgitation and tricuspid regurgitation were detected. Ultrasound diagnosis: a moderately echogenic mass in the left atrium of the fetus, and mucinous tumours could not be excluded. We repeated the examination 3 weeks later, the fetal cardiothoracic area ratio was 0.38, and the volume of the mass also increased to 1.6cm×0.8cm, and the fetus developed paroxysmal tachycardia, which lasted more than a minute, and a small amount of fluid was detected in the pericardial cavity. Considering the possible adverse prognosis, the pregnant woman opted for termination of pregnancy after MDT. We performed an autopsy of the fetus: dissection of the left heart revealed an irregular mass attached to the mitral annulus, with a smoother surface and peritoneal coating, and HE staining confirmed the diagnosis of a mucinous tumour of the fetal heart. The main purpose of prenatal echocardiography is to determine the presence of the tumour, the location of the attachment, the involvement of the heart valve, and the number of tumours. In this case, the mass is located at the mitral annulus, and the mass increases significantly in a short period of time, and there is a tendency of adverse events. If pregnancy continues, severe arrhythmia or fetal heart failure may occur. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.