Question 20#

A 62-year-old woman attends clinic following an ED attendance 6 weeks previously with a one-week history of palpitations. She was diagnosed with AF at the time and commenced on aspirin and a beta-blocker. Her echocardiogram showed no significant abnormalities and her ECG in clinic today confirms atrial fibrillation with a ventricular rate of 70 bpm. She continues to get occasional palpitations and would like to be considered for cardioversion.
What do you advise?

A) She needs to be warfarinized for at least 48 hours pre-cardioversion
B) Anticoagulation should be continued after successful cardioversion for at least 4 weeks
C) If a TOE rules out atrial thrombus, no anticoagulation is required post-procedure
D) Anticoagulation is not required prior to chemical cardioversion
E) Anticoagulation is not required prior to cardioversion as her CHADS2 score is zero

Correct Answer is B


Patients should be anticoagulated with a therapeutic INR (>2) for at least 3 weeks prior to cardioversion. Anticoagulation should be continued for at least 4 weeks post-cardioversion as ‘atrial stunning’ may occur. Anticoagulation is required prior to both chemical and electrical cardioverison. If a patient has not had oral anticoagulation for at least 3 weeks, it is reasonable to perform DC cardioversion if a TOE rules out left atrial thrombus. However, LMWH should be commenced prior to a TOE-guided cardioversion and continued post-cardioversion until the target INR is reached with oral anticoagulation.