Patent Foramen Ovale (PFO) Closure

The foramen ovale is a communication between the left and right sides of the heart that allows blood to bypass the lungs in a developing fetus, and normally closes after birth when the baby begins breathing. It does not close completely (remains patent) in about 20% of the general population, and may be an important cause of stroke in people under the age of 50. While stroke is uncommon in this age group anyway, about 50% of those who do have some form of stroke and are aged less than 50 have a patent foramen ovale (PFO).

The risk of recurrence of stroke or death is believed to be around 3.8 to 5.5% per year; closure of the PFO seems to reduce this risk by about half, to approximately 2% per year. Closure of a PFO is recommended under these circumstances, and can be done percutaneously via a catheter (a long plastic tube) inserted in a vein in the groin, thus avoiding open heart surgery. It is estimated that 50 to 70 New Zealand patients per year fulfil the criteria for PFO closure.