Randomized comparison between dexmedetomidine-remifentanil and midazolam-fentanyl for deep sedation during catheter ablation of atrial fibrillation

The efficacy of dexmedetomidine for radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) has not been well established. We evaluated the efficacy and safety of sedation using dexmedetomidine with remifentanil compared to conventional sedative agents during RFCA for AF. A total of 240 patients undergoing RFCA for AF were randomized to either the dexmedetomidine (DEX) group (continuous infusion of dexmedetomidine and remifentanil) or the midazolam (MID) group (intermittent injections of midazolam and fentanyl) according to sedative agents. Non-invasive positive pressure ventilation was applied to all patients during the procedure. The primary outcome was patient movement during the procedure resulting in a 3D mapping system discordance, and the secondary outcome was adverse events including respiratory or hemodynamic compromise. During AF ablation, the incidence of the primary outcome was significantly reduced for the DEX group (18.2% vs. 39.5% in the DEX and the MID groups, respectively, p < 0.001). The frequency of a desaturation event (oxygen saturation < 90%) did not significantly differ between the two groups (6.6% vs. 1.7%, p = 0.056). However, the incidences of hypotension not owing to cardiac tamponade (systolic blood pressure < 80 mmHg, 19.8% vs. 8.4%, p = 0.011) and bradycardia (HR < 50 beats/min: 39.7% vs. 21.8%, p = 0.003) were higher in the DEX group. All efficacy and safety results were consistent within the predefined subgroups. The combined use of dexmedetomidine and remifentanil provides higher stability sedation during AF ablation, but can lead to more frequent hemodynamic compromise compared to midazolam and fentanyl.