Infants with a patent foramen ovale and no other heart defects do not have symptoms.
Signs and tests
An echocardiogram can be done to diagnose a PFO. If the PFO is not easily seen, a cardiologist can perform a "bubble test." Saline solution (salt water) is injected into the body as the cardiologist watches the heart on an ultrasound (echocardiogram) monitor. If a PFO exists, tiny air bubbles will be seen moving from the right to left side of the heart.