Patients With Patent Foramen Ovale and Endocardial Device Leads on Apixaban for Prevention of Paradoxical Emboli


About this study

Patients with a patent foramen ovale in the setting of endocardially placed cardiac implantable electronic devices such as pacemakers, defibrillators, or resynchronization therapies are likely at higher risk for paradoxical embolic events from device lead thrombus. The investigators are conducting this study to determine if the anticoagulant medication Apixaban is more effective at reducing MRI detected brain lesions compared to placebo.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.


  • A clinical indication for a trans venous pacemaker, ICD, or CRT device, or presence of a pre-existing endovascular CIED
  • Presence of a PFO (regardless of shunt direction) confirmed with trans-esophageal or trans-thoracic echocardiography with color flow Doppler and/or agitated saline
  • Absence of any contraindication for anticoagulation
  • Absence of a clinical indication for systemic anticoagulation
  • Ability to give informed consent for the trial
  • Able to undergo head MRI and consent for MRI study to be performed in presence of CIED


  • Patients with a survival expectancy of less than one year
  • Patients who require systemic anticoagulation for any established clinical indication (excluding the presence of PFO with CIED)
  • Patients with an atrial or ventricular septal defect that is hemodynamically significant and requires repair as suggested by the ACC/AHA 2008 guidelines on evaluation and treatment of adult congenital heart diseases
  • Absence of a CIED or no clinical indication for a trans venous CIED
  • Contraindication to undergoing an MRI
  • Patients with an active infection that cannot be treated successfully prior to randomization
  • Women who are pregnant or breastfeeding, or women of child-bearing potential who do not wish to use an effective method of birth control during the course of study in a manner such that the risk of failure is minimized
  • Currently enrolled in another investigational device or drug study, or less than 30 days since ending another investigational device or drug study(s), or receiving other investigational agent(s)
  • Known sensitivity to any of the active substances or their excipients to be administered during dosing with study medication

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status

Rochester, Minn.

Mayo Clinic principal investigator

Samuel Asirvatham, M.D.

Closed for enrollment

More information


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