Dextroposition of the fetal heart

Dextroposition of the fetal heart
a short review

Normally the fetal heart lies on left side of the chest at left of the spine with the apex pointing to left.
Dextroposition is defined as most of the normally connected fetal heart, is found on the right side of the fetal chest with the apex pointing to the left .
Dextroposition of the fetal heart is an uncommon finding on prenatal ultrasonography.
When the fetal heart is displaced from the normal position in the chest, intracardiac and extracardiac fetal anomalies may be present. It may be caused by a variety of fetal abnormalities. A reported cause is external compression of the fetal heart and mediastinum, shifting the heart toward the right side of the fetus, as is the case of left-sided congenital diaphragmatic hernia in which the fetal stomach and intestines displaced the heart into the right side of the chest or compression and mass effect
in congenital cystic adenomatoid malformation of the lung.
Hypoplasia of the right lung may result to shift the heart to the right to fill the void in the right hemithorax as has been reported in association with the scimitar syndrome, which is described by dextroposition of the heart, maldevelopment of the right lung, and anomalous pulmonary venous return that drains into the vena cava. A rare cause of cardiac dextroposition in the fetus is the Poland syndrome.
Intracardiac anomalies may be also common in cases of dextroposition, indicating a possible developmental link. Comstock et al have hypothesized that the right-sided fetal heart may be due to abnormal looping during cardiac development.
Although some cases may have chromosomal abnormalities , the finding of dextroposition warrants amniocentesis for karyotype. Rarely dextroposition may be an isolated finding.
So, dextroposition of the fetal heart is an unusual finding frequently associated with intracardiac and extracardiac
anomalies. When dextroposition is noted, a targeted ultrasound, fetal echocardiogram, and fetal
karyotype should be offered.
This findings may be important information for patient counseling.

REFERENCES

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