Rapidly Reversible Monitored Anesthesia Care with Remimazolam and Flumazenil Reversal for Transcatheter Aortic Valve Replacement: A Randomized Controlled Trial

Background/Objectives: Monitored anesthesia care (MAC) is increasingly used for transcatheter aortic valve replacement (TAVR), where rapid recovery of consciousness may facilitate early postoperative neurological assessment. Remimazolam provides sedation that can be pharmacologically reversed with flumazenil. We compared emergence from sedation between a remimazolam–flumazenil-based MAC strategy and a conventional dexmedetomidine-based strategy in patients undergoing transfemoral TAVR. Methods: In this single-center randomized controlled trial, 84 patients undergoing transfemoral TAVR were randomized 1:1 to remimazolam–remifentanil (R group) or dexmedetomidine–propofol–remifentanil (D group) MAC. Flumazenil was administered at the initiation of the postoperative awakening attempt in the R group. The primary outcome was arousal time, assessed using two prespecified measures: time from discontinuation of all anesthetic infusions to arousal and time from initiation of the postoperative awakening attempt to arousal. Arousal was defined as a Modified Observer’s Assessment of Alertness/Sedation score of 5. Results: Eighty-three patients were included in the analysis (R group, n = 42; D group, n = 41). The time from discontinuation of all anesthetic infusions to arousal was shorter in the R group than in the D group (19.05 [15.77–23.59] vs. 24.09 [19.25–34.78] min; p = 0.0045). The time from initiation of the awakening attempt to arousal was also shorter (0.60 [0.33–1.00] vs. 1.00 [0–4.72] min; p = 0.0117). No patient in the R group required rescue propofol. No significant between-group differences were observed in major procedural or postoperative outcomes. Conclusions: A remimazolam-based MAC strategy with flumazenil reversal provided faster and more reliable emergence from sedation than a conventional dexmedetomidine-based strategy during transfemoral TAVR. These findings suggest that a reversible sedation strategy may facilitate rapid recovery of consciousness when early postoperative assessment is desired, although its impact on neurological or other clinical outcomes remains to be established.