Comparison Between the Acurate Neo and the Acurate Neo 2 Transcatheter Heart Valve System: Impact of Midframe Under-Expansion.

BACKGROUND: Transcatheter aortic valve implantation (TAVI) with the Acurate Neo has been linked to a significant incidence of paravalvular leakage (PVL), addressed by the Acurate Neo 2 incorporating an active sealing skirt. Recent findings suggest that midframe under-expansion is associated with worse outcomes. AIMS: We investigated the hemodynamic and clinical outcomes after TAVI with Acurate Neo 2 compared to Acurate Neo and assessed the impact of midframe under-expansion. METHODS: Patients who received Acurate Neo (n = 124) or Acurate Neo 2 (n = 133) between February 2018 and December 2021 (switch to Acurate Neo 2 in November 2020) were included. The primary outcomes were VARC-3 defined device success and early safety. RESULTS: Device success was higher with Acurate Neo 2 compared with Acurate Neo (94.7% vs. 86.3%, p = 0.020), as was early safety (87.2% vs. 74.2%, p = 0.008). The rate of mild/moderate PVL was significantly lower in Acurate Neo 2. Kaplan-Meier estimated 1-year survival (Acurate Neo 2: 87.8% vs. Acurate Neo: 89.0, p = 0.930) and freedom from the combined clinical endpoint death, stroke, myocardial infarction, and heart failure rehospitalization at 1 year (Acurate Neo 2: 81.2% vs. Acurate Neo: 79.3%, p = 0.528) were comparable between groups. A long-term analysis of these endpoints revealed no difference between groups. Midframe under-expansion occurred in 13.3% and was associated with lower freedom from the combined clinical endpoint at 1 year, irrespective of prosthesis generation. CONCLUSION: Acurate Neo 2 demonstrated significant improvements in device success and early safety compared to Acurate Neo. Midframe under-expansion occurred with both generations and was associated with worse clinical outcomes within the first year.