Below is an instruction from Human. Write a response.
    ### Instruction:
    How to diagnose Atrial Fibrillation ?
    ### Response:
    Atrial fibrillation (AF) is diagnosed based on your medical and family histories, a physical exam, and the results from tests and procedures.
                
Sometimes AF doesn't cause signs or symptoms. Thus, it may be found during a physical exam or EKG (electrocardiogram) test done for another purpose.
    