Foramen Ovale is Open Underlying Cause
The cause for atrial septal defect is unknown. For some reason, the atrial septum does not completely close as the heart forms in the fetus. The atrial septum is the wall that separates the upper chambers of the heart, called atria. The presence of the atrial septal defect results in the abnormal flow of blood from the left atrium into the right atrium.
Continue to Foramen Ovale is Open Anatomy
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