Arterial Versus Venous Activated Clotting Time (ACT) Measurements During Atrial Fibrillation Ablations

Matched/paired venous ACT samples will be drawn at the same time as arterial ACT samples to compare the results agreement between venous and arterial ACTs. Subjects undergoing atrial fibrillation ablations will continue to have Heparin dosed on the arterial ACT sample results only per the standard of care. Heparin will not be administered based on venous ACT levels obtained during this study.