A patent foramen ovale is a small, flaplike opening in the wall between the upper chambers of the heart. Most people will not have any signs or symptoms directly from PFO at all.Possible PFO symptoms include: Stroke. Infants with a PFO and no other heart defects do not have symptoms. Some adults with PFOs also suffer from migraine headaches. Patent foramen ovale symptoms manifest as migraines, shortness of breath when getting up and standing, and a higher risk for certain kinds of strokes. Most of the time, PFO itself causes no symptoms. Sometimes symptoms do result from the complications of PFO, like stroke. What are symptoms of a patent foramen ovale? Most of the time, a PFO itself causes no symptoms.