What is a patent foramen ovale (PFO)?

A PFO is present in everyone at the time of birth. When you are a fetus, there is no need for blood to be sent to the lungs because you get all of your oxygen from her mother’s blood. There is a flap between two chambers of the heart that allows blood to be diverted as it returns to the heart so that I can be sent back out to the body. At the time of birth, the pressures in the heart change rapidly, and this flap normally closes and scars over. In about 20% of people, however, the flap remains open. This is called a patent foramen ovale.