Current evidence for closure of a patent foramen ovale for cryptogenic stroke prevention.

A patent foramen ovale (PFO) has long been implicated as a potential mechanism for cryptogenic stroke (CS), which accounts for up to 40% of all cases of ischaemic stroke. Although there is a strong association between a PFO and CS, there is less evidence that percutaneous closure of the defect, as opposed to medical therapy with antithrombotics or anticoagulants, is the most effective form of secondary prevention. The aim of this review is to examine the evidence comparing percutaneous closure with medical therapy, with a particular focus on three recently published randomised controlled trials.