Persistent Atrial Fibrillation (AF)is Diagnosed in a Patient Who Has

Persistent atrial fibrillation (AF) is diagnosed in a patient who has valvular disease,and the cardiologist has prescribed warfarin (Coumadin) .The patient is scheduled for electrical cardioversion in 3 weeks.The patient asks the primary care nurse practitioner (NP) why the procedure is necessary.The NP should tell the patient:

A) this medication prevents clots but does not alter rhythm.
B) if the medication proves effective, the procedure may be canceled.
C) there are no medications that alter the arrhythmia causing AF.
D) to ask the cardiologist if verapamil may be ordered instead of cardioversion.