Safety of Atrial Defibrillation Shocks Synchronized to Narrow and Wide QRS Complexes During Atrial Pacing Protocols Simulating Atrial Fibrillation in Dogs

Abstract

In this study, ADS synchronized to NQRS complexes appeared to be safe regardless of the preceding RR interval. In the presence of LBBB or RBBB, RR intervals preceding the ADS of >345 ms at baseline and >380 ms in the presence of procainamide would have been required to avoid VF. Alternatively, ADS delivered 50 ms after the onset of the RV electrogram appeared to be safe in all circumstances regardless of the preceding RR interval.