Patent Foramen Ovale and Stroke: Should PFOs Be Closed in Otherwise Cryptogenic Stroke?
Since initial reports of its association with ischemic stroke appeared in 1988, there has been continued controversy regarding the existence and strength of the association between patent foramen ovale (PFO) and ischemic stroke. Many case-control studies have reported an association between incident cryptogenic ischemic stroke and PFO, yet population-based studies have failed to confirm this association. Studies of the risk of recurrent stroke in patients with cryptogenic stroke with or without PFO have not shown an increased risk of recurrent stroke in patients with PFO. Meanwhile, use of devices to close PFOs and atrial septal defects percutaneously has increased dramatically since their introduction. Completion of the randomized clinical trials of PFO closure currently in progress is vital to determine if the benefits of PFO closure in cryptogenic stroke outweigh its risks.
KeywordsPatent foramen ovale Stroke Cryptogenic stroke Paradoxical embolism Cerebral infarction Atrial septal aneurysm Patent foramen ovale closure Hypercoagulable state
Dr. Jin-Moo Lee has received grant support from National Institutes of Health P50 NS055977, P01 NS032636, R01 NS048283, and R01 NS067905, and has been a site principal investigator for the following clinical trials: RESPECT, APCAST, SWISS, and IRIS. No other potential conflicts of interest relevant to this article were reported.
Papers of particular interest, published recently, have been highlighted as: • Of Importance, •• Of Major Importance
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