Patent foramen ovale

Background

Patent foramen ovale (PFO) is a flap-like opening between the atrial septa primum and secundum at the location of the fossa ovalis that persists after 1 year of age. This inter-atrial communication gives potential for right-to-left shunting in the cardiovascular system. Although most patients with an isolated PFO are asymptomatic, there is increasing evidence being found that PFO is the culprit in paradoxical embolic events and therefore, the relative importance of the anomaly is being re-evaluated.

Clinical Features

• History of stroke or TIA of undefined etiology
• Migraine or migraine-like symptoms
• Neurologic decompression sickness (seen in scuba divers)
• Acute myocardial infarction
• Systemic embolism, such as renal infarction
• Fat embolism
• Paradoxical embolism caused by right atrial tumors that increase right atrial pressure
• Left-sided valve disease in carcinoid syndrome