Importance In patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI), asymmetric valve expansion can estimate prosthetic dysfunction and death. Postdilation has shown promising results in optimizing valve geometry in observational studies; however, randomized evidence is currently lacking. Objective To determine the efficacy of routine postdilation on transcatheter heart valve (THV) geometry and hemodynamic performance, and associated safety outcomes. Design, Setting, and Participants DUOTAP was a single-center, single-blinded randomized clinical trial. Recruitment took place from January 2025 to April 2026 and end points were assessed periprocedurally (fluoroscopy) at 30 days (adverse events) and at 3 months (computed tomography [CT]). The trial was conducted at a high-volume tertiary referral center, the Medical University of Vienna, Austria. Included patients had severe AS suitable for transfemoral TAVI with a balloon-expandable THV and without high-risk features on preprocedural CT or coronary angiography and were randomized in a 1:1 ratio, stratified by THV size, to routine postdilation vs no postdilation. These data were analyzed from July 2026 to September 2026. Intervention Routine postdilation using the original delivery balloon at the identical filling volume. A sham procedure was performed in the control group. Main Outcomes and Measures The fluoroscopic THV asymmetry index served as primary end point. Further fluoroscopic and CT-derived measures of valve geometry, hypoattenuated leaflet thickening (HALT), paravalvular leak (PVL), and THV hemodynamics on echocardiography, and freedom from major procedural adverse events served as secondary end points. Results Overall, 148 patients (median [IQR] age, 81 [77-85] years; 69 female [46.6%] and 79 male [53.4%]; median EuroSCORE-II, 2.3%) underwent randomization (n = 74 intervention vs n = 74 control). Intervention yielded a 70% lower THV asymmetry index compared with control (median: 1.2% vs 2.8%; geometric mean ratio: 0.30; 95% CI, 0.18-0.47; P < .001), with consistent effects across prespecified subgroups, induced by frame height reduction across the outer curve. Additionally, intervention yielded numerically larger THV diameters on fluoroscopy and significantly larger THV areas at the inflow, midframe, and outflow level on CT. HALT and mild or worse PVL were significantly less frequent and the Doppler Velocity Index was significantly higher in the intervention group. No differences in procedure-related adverse events between groups were recorded (χ2 test: P = .36). Conclusions and Relevance In this randomized clinical trial, postdilation led to reduced THV asymmetry, optimized geometry, and improved hemodynamic performance, without increasing procedure-related adverse events. These results support the use of routine postdilation to optimize THV geometry and hemodynamics in suitable patients. Trial Registration ClinicalTrials.gov Identifier: NCT07477002.
