American Heart Association -- The American Heart Association and the American College of Cardiology are calling on doctors to enroll more patients in clinical trials for catheter-based closure of patent foramen ovale (PFO), a condition caused when an opening between the two chambers of the heart fails to close at birth. Due to a lack of conclusive research on the management of PFO after stroke or transient ischemic attack, there is currently no clearly established treatment for this condition.
