PFO closure is a minimally invasive catheter procedure in which a small device is implanted via a catheter inserted into a large vein in the groin. Most PFOs don't need any treatment.If your child needs surgery for another heart defect, the PFO may be closed at the time of the surgery. During transcatheter repair, a healthcare provider inserts a device that can plug up the PFO. A patent foramen ovale is a small, flaplike opening in the wall between the upper chambers of the heart. However, it may cause serious complications under certain circumstances. Congenital lesion resulting in a defect in the fossa ovalis smaller than an atrial septal defect. It requires no treatment or followup.