DOAC in Chinese Patients With Atrial Fibrillation

Eligible subjects will receive additional blood tests for determination of DOAC levels and pharmacogenomic studies. Participants shall undergo DOAC level testing at peak, trough, 24, and 48 hours after discontinuation of DOAC for elective medical procedures. We shall also record their baseline demographics, clinical assessments, medical comorbidities, blood parameters, and concurrent medications. We shall minimize the blood taking by combining DOAC levels and blood tests essential for routine medical consultation and pre-procedural workup. Blood taking will only be performed by clinicians or phlebotomists who are experienced in the procedure.