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

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.