Remimazolam Versus Dexmedetomidine for Monitored Anesthesia Care in Patients Undergoing Transfemoral Transcatheter Aortic Valve Implantation: A Randomized Clinical Trial

Background/Objectives: Monitored anesthesia care is increasingly used for transfemoral transcatheter aortic valve implantation (tf-TAVI), but the optimal sedative regimen remains uncertain. We compared remimazolam with dexmedetomidine during tf-TAVI. Methods: In this single-center randomized trial, 34 patients were assigned 1:1 to remimazolam or dexmedetomidine. Primary outcomes were the number of intraoperative hypotensive episodes, defined as mean arterial pressure <65 mmHg requiring vasopressor treatment, and cumulative phenylephrine and norepinephrine doses. Secondary outcomes included hemodynamic and physiological variables, regional cerebral oxygen saturation (rSO2), arterial blood gases, recovery time, surgeon requests for deeper sedation, and procedural outcomes. Longitudinal variables were analyzed using generalized estimating equations with Holm adjustment for time-specific comparisons. Results: No significant between-group differences were detected in intraoperative hypotensive episodes or cumulative phenylephrine and norepinephrine doses, and no significant group-by-time interactions were observed for blood pressure. Both left and right rSO2 showed significant group-by-time interactions, with higher remimazolam values at selected time points after Holm adjustment. Arterial carbon dioxide tension was higher and arterial pH lower with remimazolam immediately before rapid ventricular pacing and at procedure completion. Recovery was faster with remimazolam (mean ± standard deviation, 13.5 ± 7.2 vs. 32.4 ± 12.5 min; p < 0.001), and surgeon requests for deeper sedation were less frequent (11.8% vs. 76.5%; p < 0.001). Conclusions: Remimazolam was associated with faster recovery and fewer surgeon requests for deeper sedation; however, the trial was not designed or powered to establish equivalence for hypotensive episodes, vasopressor requirements or hemodynamic outcomes.