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

PARADOX Trial: A Prospective, Double-Blind, Randomized Controlled Trial in Patients With Patent Foramen Ovale and Endocardial Device Leads on Apixaban for Prevention of Paradoxical Emboli

Status
Withdrawn
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02378623
Acronym
PARADOX
Enrollment
0
Registered
2015-03-04
Start date
2015-05-31
Completion date
2020-01-31
Last updated
2018-11-16

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Cardiac Implantable Electronic Device, Patent Foramen Ovale

Keywords

paradoxical embolism, lead thrombus, ICD, Pacemaker, Cognitive decline, Stroke, TIA

Brief summary

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.

Detailed description

This is a prospective, double-blinded, placebo-controlled, randomized controlled trial (RCT). 400 patients who meet the study eligibility criteria and consent for enrollment will be randomized in a 1:1 ratio to intervention with apixaban or control group with placebo. The randomization will be performed by a computer generated block randomization protocol. The majority of patients will begin intervention with Apixaban or placebo at the time of cardiac device placement (n approximately 300), and at least a quarter of the randomized patients (n ≥100) will include preexisting CIED (≥6 months) in place. Each patient will undergo a baseline MRI and a comprehensive cognitive screening examination. Repeat MRI and cognitive assessment will be performed at a follow-up period of two years from date of randomization (or less if clinical stroke/TIA occurs prior to this follow-up period). All subjects will receive a phone call at 6 months, 12 months, and 18 months post-randomization to assess for endpoints and adverse events, as well as changes in clinical status, medications, and to assess study medication compliance.

Interventions

DRUGApixaban

Patients who meet the study eligibility criteria and consent for enrollment will be randomized in a 1:1 ratio to intervention with apixaban or control group with placebo. The randomization will be performed by a computer generated block randomization protocol. Randomization will be stratified according to pre-existing CIED (≥6 months) vs. new implantation (\<6 months from date of implant), in order to ensure at least 25% of patients have longstanding lead placement.

DRUGPlacebo

Patients who meet the study eligibility criteria and consent for enrollment will be randomized in a 1:1 ratio to intervention with apixaban or control group with placebo. The randomization will be performed by a computer generated block randomization protocol. Randomization will be stratified according to pre-existing CIED (≥6 months) vs. new implantation (\<6 months from date of implant), in order to ensure at least 25% of patients have longstanding lead placement.

Sponsors

Bristol-Myers Squibb
CollaboratorINDUSTRY
Mayo Clinic
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
SINGLE_GROUP
Primary purpose
PREVENTION
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
18 Years to 85 Years
Healthy volunteers
No

Inclusion criteria

Inclusion: * 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 Exclusion: * 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

Design outcomes

Primary

MeasureTime frameDescription
Increase in number of new brain lesions detected on MRI ≥3 mm in size at 2 years post-baseline MRI (or earlier if premature termination of study follow-up).2 yearsThe primary objective of this study is to determine whether medical therapy with apixaban lowers the rate of new MRI cerebral lesions compared to placebo in pacemaker, defibrillator, and resynchronization device therapy recipients with a PFO

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026