200 J-first, fixed-escalation biphasic electrical cardioversion for atrial fibrillation >48 hours in the emergency department: a single-centre retrospective observational study

Open Heart, vol. 13, pp. e003875

Abstract

BACKGROUND: Guidelines permit up to 360 J for synchronised biphasic electrical cardioversion (ECV) in atrial fibrillation (AF) lasting >48 hours. The CHESS randomised trial reported higher first-shock success with fixed 360 J versus a low-escalation 125-150-200 J sequence. Much of this evidence used adhesive pads without manual pressure and anterior-posterior positioning. We evaluated a 200 J-first, fixed-escalation biphasic ECV protocol delivered with a standardised technique in an emergency department (ED). METHODS: Single-centre retrospective observational study of consecutive adults undergoing elective ECV for symptomatic AF >48 hours (2019-2021). Procedures used hand-held paddles with firm chest pressure in the anterolateral (AL) position under deep sedation. The predefined sequence was 200→300→360 J if needed. The primary outcome was restoration of sinus rhythm (SR) documented on a 12-lead ECG within 120 min. Secondary outcomes were first shock success at 200 J, cumulative efficacy, SR to discharge without post-ECV antiarrhythmics, adverse events and subgroup efficacy. Results were contrasted descriptively with 360 J-first cohorts (CHESS). RESULTS: Of 451 ECV procedures identified, 374 were eligible. The primary outcome was achieved in 97.3% (364/374; 95% CI 95.5 to 98.7). First-shock success with 200 J was 88.0% (329/374; 95% CI 84.3 to 90.9). Escalation to 300 J and 360 J was required in 44 and 15 patients. SR was maintained to discharge in converted patients. Two minor adverse events occurred (2/374, 0.5%) and no serious adverse events were recorded. CONCLUSIONS: A 200 J-first, fixed-escalation biphasic protocol with a standardised technique (manual paddles, firm pressure, AL placement) achieved high first-shock and excellent cumulative efficacy for AF>48 hours in real-world ED care without routine pharmacologic adjuncts. Findings support considering a 200 J-first approach and motivate pragmatic multicentre randomised controlled trials directly comparing 200 J-first versus 360 J-first under harmonised technique with objective safety endpoints.

Authors 4

1. Jakub Nożewski

   Nicolaus Copernicus University

   Affiliation as printed

   Emergency Medicine, Nicolaus Copernicus University in Torun, Bydgoszcz, Poland

2. Zbigniew Siudak

   Jan Kochanowski University

   Affiliation as printed

   Jan Kochanowski University, Kielce, Swietokrzyskie, Poland

3. Barbra E. Backus Aachen Emergency Medicine

   Leiden University Medical Center

   Affiliation as printed

   Emergency Medicine, LUMC, Leiden, Zuid-Holland, The Netherlands

4. Aristomenis Exadaktylos

   University of Bern

   Affiliation as printed

   Emergency Medicine, Faculty of Medicine, University of Bern, Bern, Switzerland