1. Wenaweser et al, Transcatheter aortic valve implantation with the NVT Allegra transcatheter heart valve system: first-in-human experience with a novel self-expanding transcatheter heart valve, EuroIntervention, 2016;
2. Lemos, Clinical performance of a novel transfemoral, supra-annular, early functional, retrievable transcatheter aortic valve system, PCR London Valves 2017 presented at Late Breaking Trials;
3. Schaefer et al, Thirty-day outcomes of a novel transcatheter heart valve to treat degenerated surgical valves: the VIVALL multicentre, single-arm, pilot study; EuroIntervention, 2019;
4. Data on file;
5. Sathananthan et al, Impact of implant depth on hydrodynamic function with the ALLEGRA transcatheter heart valve following, valve-in-valve intervention. EuroIntervention, 2019;
6. J.A. Baz Alonso et al ,First-In-Human Experience of the New Fully Repositionable IMPERIA Delivery System to Implant the ALLEGRA Transcatheter Heart Valve in Patients With Severe Calcific Aortic Stenosis or Degenerated Surgical Bioprosthesis: Thirty-Day Results of the EMPIRE I Study” Structural Heart 9, 2025
7. Leone PP et al, TAVI-SMALL Investigators. Prosthesis-patient mismatch after transcatheter implantation of contemporary balloon-expandable and self-expandable valves in small aortic annuli. Catheter Cardiovasc Interv. Nov., 2023;
8. Corevalve - SURTAVI: N.M. Van Mieghem, “Self-expanding Transcatheter vs Surgical Aortic Valve Replacement in Intermediate-Risk Patients 5-Year Outcomes of the SURTAVI Randomized Clinical Trial” – JAMA Cardiol. 2022;7(10):1000-1008. doi:10.1001/jamacardio.2022.2695
9. Sapien XT, Sapien 3 - PARTNER 2 Trial and Registry: J. Ternacle, “Prosthesis-Patient Mismatch After Aortic Valve Replacement in the PARTNER 2 Trial and Registry” – JAMA Cardiol. 2022;7(10):1000-1008. doi:10.1001/jamacardio.2022.2695;
10. Evolut™ R, PRO, PRO+ - STS/ACC TVT Registry: G.H. L. Tang “Outcomes of Prosthesis-Patient Mismatch Following Supra-Annular Transcatheter Aortic Valve Replacement: From the STS/ACC TVT Registry” – JACC Cardiovasc Interv 2021 Volume 14, Issue 9, 10 May 2021, Pages 964-976-10.1016/j.jcin.2021.03.040;
11. Corevalve - Retrospective Analysis: M. D. C. Leon del Pino “Prosthesis-patient mismatch after transcatheter aortic valve replacement: prevalence and medium term prognostic impact” – The International Journal of Cardiovascular Imaging – 2019 Volume 35, pages 827–836, (2019) - 10.1007/s10554-018-01519-z;
12. Sapien, Sapien XT, Sapien 3 - Single-center registry: N. Schofer “Prosthesis-patient mismatch after transcatheter aortic valve implantation: prevalence and prognostic impact with respect to baseline left ventricular function” – Eurointervention - 2019 Mar 20;14(16):1648-1655. doi: 10.4244/EIJ-D-18-00827;
13. Portico™ - Single-center registry: N. Schofer “Prosthesis-patient mismatch after transcatheter aortic valve implantation: prevalence and prognostic impact with respect to baseline left ventricular function” – Eurointervention - 2019 Mar 20;14(16):1648-1655. doi: 10.4244/EIJ-D-18-00827;
14. Corevalve, Evolut™ R, Acurate neo™ - Single-center registry: N. Schofer “Prosthesis-patient mismatch after transcatheter aortic valve implantation: prevalence and prognostic impact with respect to baseline left ventricular function” – Eurointervention - 2019 Mar 20;14(16):1648-1655. doi: 10.4244/EIJ-D-18-00827;
15. Sapien THV, Sapien XT, Sapien 3 - Propensity Matched: T. Okuno “Prosthesis-Patient Mismatch Following Transcatheter Aortic Valve Replacement With Supra-Annular and Intra-Annular Prostheses” – JACC Cardiovasc Interv 2019 Volume 12, Issue 21, 11 November 2019, Pages 2173-2182 - https://doi.org/10.1016/j.jcin.2019.07.027;
16. Evolut™, CoreValve - Propensity Matched: T. Okuno “Prosthesis-Patient Mismatch Following Transcatheter Aortic Valve Replacement With Supra-Annular and Intra-Annular Prostheses” – JACC Cardiovasc Interv 2019 Volume 12, Issue 21, 11 November 2019, Pages 2173-2182 - https://doi.org/10.1016/j.jcin.2019.07.027;
17. Sapien - Retrospective Analysis: A. Theron “Patient-prosthesis mismatch in new generation trans-catheter heart valves: a propensity score analysis” - Eur Heart J Cardiovasc Imaging - 2018 Feb 1;19(2):225-233. doi: 10.1093/ehjci/jex019;
18. Sapien 3 - Propensity Matched : V. Mauri “Short-Term Outcome and Hemodynamic Performance of Next-Generation Self-Expanding Versus Balloon-Expandable Transcatheter Aortic Valves in Patients With Small Aortic Annulus: A Multicenter Propensity-Matched Comparison” – Circ Cardiovasc Interv. 2017 Oct;10(10):e005013. doi: 10.1161/CIRCINTERVENTIONS.117.005013;
19. Acurate neo™ - Propensity Matched : V. Mauri “Short-Term Outcome and Hemodynamic Performance of Next-Generation Self-Expanding Versus Balloon-Expandable Transcatheter Aortic Valves in Patients With Small Aortic Annulus: A Multicenter Propensity-Matched Comparison” – Circ Cardiovasc Interv. 2017 Oct;10(10):e005013. doi: 10.1161/CIRCINTERVENTIONS.117.005013.
20. Data on file;
21. Christie GW, Barratt-Boyes BG. On stress reduction in bioprosthetic heart valve leaflets by the use of a flexible stent. Journal of cardiac surgery 1991;6:476-81;
22. Data on file;
23. Hatoum et al, Comparison of self and balloon-expanding turbulence pressure recovery, JTCVS 2022;
24. Schäfer, Acute outcomes of a novel self-expanding transcatheter heart valve, Presented at DGK 2018;
25. Moreno et al, Transcatheter aortic valve implantation for degenerated aortic valves: Experience with a new supra-annular device. The Spanish Allegra valve-in-valve (SAVIV) registry, CCI, 2021;
26. Dvir et al, VIVID Registry: Transcatheter Aortic Valve Implantation in Failed Bioprosthetic Surgical Valves, JAMA, 2014;
27. D. Tchétché et al, VIVA: Transcatheter Aortic Valve Replacement for Failed Surgical Aortic Bioprosthesis Using a Self-Expanding Device: One Year Results From the Prospective VIV post-Market Study, JACC, 2019;
28. Dvir et al, CV VIV Indication: Transcatheter Aortic Valve Replacement for Degenerative Bioprosthetic Surgical Valves Results From the Global Valve-in-Valve Registry, Circulation, 2012;
29. Deeb et al, CV US Study: 1-Year Results in Patients Undergoing Transcatheter Aortic Valve Replacement With Failed Surgical Bioprostheses, JACC, 2017;
30. Webb et al, Partner 2 VIV Registry: Transcatheter aortic valve implantation within degenerated aortic surgical bioprostheses: Partner 2 valve-in-valve registry, JACC, 2017;
31. Cabau et al, Balloon- versus self-expanding valve systems for treating small failed surgical aortic bioprostheses: the LYTEN trial, J Am Coll Cardiol, 2022;

ALLEGRA and IMPERIA are trademarks or registered trademarks of NVT AG, the holding company of NVT GmbH. ALLEGRA™ Transcatheter Heart Valve and IMPERIA™ Delivery System are CE approved medical devices (CE 0124). Third party brands are trademarks of their respective intellectual property right owners. CAUTION: The law restricts these devices to sale by or on the order of a physician and for the use by or under the direction of a physician. Indications, contraindications, warnings, and instructions for use can be found in the product labeling supplied with each device. Not available in the United States and any other country where applicable health authority product registration has not been obtained. The legal manufacturer of ALLEGRA™ and IMPERIA™ is NVT GmbH, which is part of Blue Sail Medical Co., Ltd. NVT AG and Biosensors International Group, Ltd. and its affiliates are collaborating for the commercialization of the ALLEGRA™ and IMPERIA™ medical devices. Legal manufacturer: NVT GmbH Lotzenäcker 72379 Hechingen Germany. © 2025 NVT GmbH. All rights reserved. NT-DB-120101-EN-02_2025-02.