Fetal pericardial teratomas are rare pericardial teratomas that present in utero. They are an uncommon primary cardiac tumor occurring in a fetus.

Pathology

It is a type of germ cell tumor and arises from pluripotent cells derived from all three germinal layers. In contrast to ovarian teratomas, intrapericardial teratomas usually contain no hair, sebaceous glands or squamous epithelium, although calcifications are reported.

Intrapericardial teratomas are almost always pedunculated, with attachment to the aortic root or pulmonary vessels and are invariably associated with a pericardial effusion.

Tumors can reach a large size (up to 2-3 times that of the normal fetal heart).

Location

Most are juxtaposed to the right side of the heart, causing vascular compression with growth, but left-sided teratomas have been reported. The most common origin is the base of the heart adjacent to the right atrium.

Radiographic features

Ultrasound

Most teratomas are of mixed echogenicity with cystic areas and/or calcifications. Almost all are associated with a fetal pericardial effusion. They may demonstrate increased vascularity on color Doppler.

Complications

• an associated pericardial effusion or mass effect may cause extrinsic compression on the heart and cardiac tamponade

• it also impedes venous return with resultant hydrops fetalis and fetal death

Treatment and prognosis

It is a benign tumor and in selected cases, resection can be curative. Despite its benign nature, it can carry significant morbidity and mortality due to associated complications. Intrauterine pericardiocentesis has been performed in selected cases to relieve fetal hydrops ⁹.

See also

• fetal tumors

• fetal cardiac tumors

• congenital intrapericardial teratoma: broader term