Toward a better understanding of PFO and stroke risk

A patent foramen ovale (PFO) is a remnant of the fetal circulation and may be found in approximately 25% of adults.1 Multiple case-control studies have demonstrated an association between PFO and cryptogenic ischemic stroke, particularly in younger patients.2 The mechanism for the association is presumed to be venous thromboembolism through the PFO and into the cerebral circulation (i.e., paradoxical embolization).3 Randomized studies of percutaneous PFO closure devices for secondary stroke prevention have been in progress for years with slow enrollment because of off-label use of atrial septal defect closure devices.4,5 Three of these were recently completed and none showed a reduction in their primary endpoints in intention-to-treat analyses.6–8 However, one of the studies showed a reduction in stroke risk (a secondary outcome) in a prespecified, per-protocol cohort (hazard ratio, 0.37; 95% confidence interval, 0.14–0.96) and in the as-treated cohort (hazard ratio, 0.27; 95% confidence interval, 0.10–0.75).7,8
Source: Neurology - Category: Neurology Authors: Tags: Stroke in young adults, Stroke prevention, Prognosis, Embolism EDITORIALS Source Type: research