Background: Despite the widespread use of biphasic truncated exponential (BTE) waveforms for cardioversion and defibrillation their efficacy and safety have only been compared in a few studies.
Objectives: This retrospective study aims at comparing the efficacy and safety of BTE pulsed energy (PE) and BTE low energy (LE) waveforms for cardioversion of atrial fibrillation (AF) and atrial flutter (AFL).
Methods: The patients received maximum of three BTE stacked shocks with energies: 120- 200-200J (AF treated with PE), 100-200-200J (AFL with BTE LE), 30-120-200J (AFL with PE), 30-100-200J (AFL with BTE LE). Successful cardioversion was defined as sinus rhythm restoration for at least 1 minute after the shock. The energy protocol was applied until success or maximum number of shocks was achieved. If the last BTE shock failed, a monophasic shock of 360J was delivered.
Results: From May 2008 to November 2017, 193 patients (153 PE, 40 LE) were included in the study. Both groups significantly differed in a few baseline characteristics, including the chest circumference (p<0.05). After adjustment, the success rate was not significantly different for the two waveforms (94.5% PE vs. 92.5% LE, odds ratio [95% confidence interval]: 0.25 [0.03–2.2]).There was no difference in safety: changes in troponin I levels after cardioversion were similar (p=0.25). The efficient cumulative energy was significantly associated with body surface area (β=131.5, p=0.05), AF/AFL duration (β=0.24,p=0.01) and gender (β=61.8, p=0.05).
Conclusion: In this clinical study, the difference in the observed efficacy and safety of the PE vs. LE did not reach statistical significance.
Credits: Delphine Lavignasse, ElinaTrendafilova, Elena Dimitrova, Vessela Krasteva