Patent Foramen Ovale
Also known as: PFO.
What is patent foramen ovale?
A PFO is a hole in the tissue (atrial septum) that separates the heart's two upper chambers, (right atrium and left atrium). It's present in all babies before birth, and the opening allows oxygenated blood from the mother's placenta to bypass the baby’s non-functioning lungs and send oxygen to the baby's growing body. Typically (in 75%) it closes after a baby is born and breathes. When it doesn’t close, the persistently open hole is called a PFO.
What causes patent foramen ovale?
Researchers aren’t exactly clear why PFO occurs, however genetics may play a role.
What are the symptoms of patent foramen ovale?
In most infants, a patent foramen ovale doesn’t cause any symptoms unless it occurs with other heart defects.
What are patent foramen ovale care options?
A Patent foramen ovale that is present by itself does not require treatment. If symptomatic (or if there are other heart defects), it may be sealed with a device delivered through a vein in the groin or closed with surgery.
Reviewed by: Jack Wolfsdorf, MD, FAAP
This page was last updated on: September 16, 2025 12:21 PM
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