Oral Anticoagulation Therapy Pilot Study

The objective of this study is to determine the safety of discontinuing oral anticoagulation therapy in high risk patients who have had a successful cardiac ablation and remain AF recurrence free for 3 months post ablation.

Patients undergoing successful cardiac ablation for atrial fibrillation who remain AF recurrence-free 3 months after successful ablation and continue to meet the inclusion/exclusion criteria will be screened for enrollment in the trial. After fulfilling all of the inclusion/exclusion criteria, patients who consent to participate in the study and remain AF recurrence-free will be randomized to one of two study arms: (1) OAT Withdrawal (Test) Group or (2) OAT (Control) Group and participate in the Evaluation Period (12 months).

Eligibility Criteria:
Inclusion Criteria:

1. Successful cardiac ablation for AF
2. Documented freedom from AF recurrence (symptomatic or asymptomatic arrhythmic recurrences lasting longer than 30 seconds) 3 months after successful cardiac ablation (AF recurrence during 3-month blanking period is excluded).
3. Patient must have been on a commercially approved anticoagulation therapy for at least two (2) months prior to randomization in the OAT Study.
4. CHADS2 score ≥ 2 or CHA2DS2-VASc score (≥3)
5. Left ventricular ejection fraction \> 25%
6. LA size \< 65
7. High risk for thromboembolic events (i.e., CHADS2 score ≥ 2 or CHA2DS2-VASc score ≥ 3) and require OAT before undergoing cardiac ablation
8. Able and willing to comply with all pre- and follow-up testing and requirements
9. Signed informed consent form
10. Age 18 years or older

Exclusion Criteria:

1. OAT required for reasons not related to AF (i.e., prosthetic valve, PV stenosis, previous pulmonary embolism, presence of spontaneous echo contrast \[SEC\] at standard echo performed at 3-months follow-up).
2. Any cardiac surgery within the past 60 days (2 months) or valvular cardiac surgical procedure at any time (i.e., ventriculotomy, atriotomy, and valve repair or replacement and presence of a prosthetic valve)
3. Previous myocardial infarction (MI) or a percutaneous coronary intervention PCI within the past 3 months
4. Awaiting cardiac transplantation or other cardiac surgery within the next 365 days (12 months)
5. Documented left atrial thrombus
6. Significant pulmonary disease, (e.g., restrictive pulmonary disease, constrictive or COPD) or any other disease or malfunction of the lungs or respiratory system that produces chronic symptoms
7. Significant medical problem that in the opinion of the investigator would preclude enrollment in this study
8. Women who are pregnant (as evidenced by pregnancy test if pre-menopausal)
9. Acute illness or active systemic infection or sepsis
10. Unstable angina
11. Contraindication to anticoagulation (i.e., heparin, warfarin or another commercially available anticoagulation medication)
12. History of blood clotting or bleeding abnormalities
13. Life expectancy less than 360 days (12 months)
14. Uncontrolled Heart Failure or NYHA Class III or IV heart failure
15. Enrollment in a clinical study evaluating another device or drug, within the past 6 months
16. Unable or unwilling to comply with protocol requirements