Background: To compare the acceptability and effectiveness of three pre -medic ation regimens for manually activated cardioversion of recurrent persistent atri al fibrillation. Methods: Eighteen patients implanted with the Jewel AF atrial d efibrillator for drug-resistant persistent atrial fibrillation only were studie d in an open-labelled randomised crossover study. Patients were assigned to sed ation (S) with midazolam elixir, analgesia(A) with morphine sulphate or combinat ion therapy(C) with dextromoramide and lorazepam. Pre-medication was taken up t o 1h before cardioversion. Patients rotated through each type of medication afte r undertaking at least one cardioversion. Visual analogue scales were completed immediately post-cardiov-ersion and 24 h later for pain, anxiety and ‘unpleas an-tness’. Higher scores represented a worse outcome. Results: After 2 years’ follow-up, 238 cardioversions were performed with S, 17 with A and 35 with C. T he mean immediate combined score for S(10.9, 95%confidence interval(CI) 8.2-13 .6) was significantly lower than for A(17.3,95%CI 15.1-19.5,P=0.01)-and for C (15.9, 95%CI 12.3-19.6, P=0.02). All patients who used S chose it as the most favourable pre-medicant. All patients who used A found it the least acceptable . Conclusion: Sedation rather than analgesia enhanced the acceptability of manua lly activated atrial defibrillation. Background: To compare the acceptability and effectiveness of three pre -medicated regimens for manually activated cardioversion of recurrent persistent atri al fibrillation. Methods: Eighteen patients implanted with the Jewel AF atrial d efibrillator for drug-resistant persistent atrial fibrillation only were studie d in an open-labeled randomized crossover study. Patients were assigned to sedtion (S) with midazolam elixir, analgesia (A) with morphine sulphate or combinat ion therapy (C) with dextromoramide and lorazepam. Pre-Medications were taken up to 1h before cardioversion . Patients rotated through each type of medication afte r undertaking at least one cardioversion. Visual analogue scales were completed immediately post-cardiov-ersion and 24 h later for pain, anxiety and ’unpleas an-tness’. Higher scores represented a worse outcome. Results: After 2 years’ follow-up, 238 cardioversions were performed with S, 17 with A and 35 with C. T he mean immediate combined score fo r S (10.9, 95% confidence interval (CI) 8.2-13 .6) was significantly lower than for A (17.3,95% CI 15.1-19.5, P = 0.01) 19.6, P = 0.02). All patients who used S chose it as the most favourable pre-medicant. All patients who used A found it the least acceptable. Conclusion: Sedation rather than analgesia enhanced the acceptability of manua lly activated atrial defibrillation.