A patent foramen ovale (PFO) is a small hole within the heart that should close at birth but fails to do so in a proportion of people. It is located between the two top chambers of the heart (the atria). It can increase stroke risk as well as the risk of decompression illness in SCUBA divers. It can allow blood clots that may form within leg veins (such as deep vein thrombosis or DVT) to bypass the lungs and enter the circulation where they could cause stroke or other complications.
The PFO can be detected by performing a trans-oesophageal echocardiogram. Closure of the PFO may be recommended to help reduce stroke risk or risk of decompression illness.
The defect is closed with a keyhole procedure usually performed under a general anaesthetic. A tube (catheter) is inserted into the vein at the top of the leg (femoral vein). It is then passed across the PFO. A double-umbrella device is then passed through the catheter and released so that it straddles the defect and closes it.
Usually PFO closure requires an overnight stay in hospital. Blood thinning medications are used after the procedure until tissue grows over the closure device. Usually aspirin is recommended lifelong and clopidogrel for the first 3 months. The closure device should be protected against infection particularly in the first 6 months by taking a dose of antibiotics 30-60 minutes before at-risk procedures such as dental work or other surgery. Heavy exertion should be avoided for the first month. Follow-up transthoracic echocardiography is usually performed at 1 month, 6 months then annually.