What is the evidence regarding the comparison of device closure and anticoagulation for preventing recurrent stroke?
A comparison of device closure and anticoagulation was not a prespecified analysis in the CLOSE trial (Patent Foramen Ovale Closure or Anticoagulants Versus Antiplatelet Therapy to Prevent Stroke Recurrence), however a post hoc underpowered analysis of recurrent stroke found no events in the device closure group and 3 events in the warfarin group, which was not a statistically significant difference. Furthermore, it is not known whether closure is superior to warfarin for long-term treatment, and an individual-level meta-analysis of all randomized trials is needed to determine whether PFO size is independently associated with response to treatment.