Synchronised DC Cardioversion
All patients underwent synchronised DC cardioversion of their
arrhythmia’s according to standard protocol. In brief, pre-procedural
electrocardiogram was obtained for confirmation of the presenting
arrhythmia and participants received general anesthesia. A Phillips
HeartStart biphasic Defibrillator XL (Phillips, Amsterdam, Netherlands)
was used for the procedure with pad placed in the anterior-posterior
position. Adhesive gel pads were used for all procedures. Once sedated,
a shock of 150J was delivered to the patient. If this was sufficient
energy to cardiovert to sinus rhythm the procedure was complete. If the
patient remained in arrhythmia, a subsequent shock of 200J was delivered
up to two more times. Following the third overall attempt, pads were
changed and a fourth and final attempt was made with an energy of 200J.
The exact energy of the shock delivered and measured impedance was
recorded from the rhythm strip of the defibrillator. A successful
cardioversion was defined as at least three consecutive beats of sinus
rhythm on the rhythm strip following cardioversion.