IMPACT registry: 1-year patient outcomes and performance of a novel aortic bioprosthetic valve in 556 patients

F. Bakhtiary¹, A. El-Sayed Ahmad¹, N. Bonaros², O. Dewald³, A. Mehdiani⁴, F. Pollari⁵, K. Lam⁶, J. strauch⁷, M. Borger⁸, R. Autschbach⁹, R. Feyrer¹⁰, R. Leyh¹¹, A. Liebold¹², M. Czesla¹³, S. Salamate¹, A. Vötsch¹⁴, D. Wendt¹⁵, A. Weber¹⁶, J. Grünenfelder¹⁷, A. Zierer^18
1Cardiac Surgery University Hospital Bonn, Germany, Bonn, Nordrhein-Westfalen ²Medical University of Innsbruck, Innsbruck, Tirol ³University Hospital Oldenburg, Germany, Oldenburg, Nordrhein-Westfalen ⁴University Hospital Duesseldorf, Germany, Duesseldorf, Nordrhein-Westfalen ⁵Klinikum Nürnberg, Nurnberg, Bayern ⁶Catharina Ziekenhuis Eindhoven, Netherlands, Eindhoven, Flevoland ⁷Herzzentrum Bergmannsheil, Bochum, Germany, Bochum, Nordrhein-Westfalen ⁸Leipzig Heart Center, Leipzig, Sachsen ⁹University Hospital RWTH Aachen, Aachen, Germany, Aachen, Nordrhein-Westfalen ¹⁰Bundeswehrzentralkrankenhaus, Koblenz, Germany, Koblenz, Rheinland-Pfalz ¹¹University Hospital Wuerzburg, Wuerzburg, Germany, Wuerzburg, Nordrhein-Westfalen ¹²University Hospital Ulm, Ulm, Germany, Ulm, Baden-Wurttemberg ¹³Hospital Passau, Passau, Germany, Passau, Bayern ¹⁴Department of Cardiovascular and Endovascular Surgery, Paracelsus Medical University, Salzburg, Austria, Salzburg, Oberosterreich ¹⁵Essen University Hospital, Essen, Germany, Essen, Nordrhein-Westfalen ¹⁶Heart Center Hirslanden, Zurich, Switzerland, Zurich, Zurich ¹⁷Heart Clinic Hirslanden, Zurich, Switzerland, Zurich, Zurich ¹⁸Kepler University Hospital Linz, Linz; and Hospital Wels-Grieskirchen, Wels, Austria, Linz, Oberosterreich

Purpose: Valve performance and clinical outcomes after surgical AVR are thought to be affected by pre-existing comorbidities, such as chronic kidney disease (CKD), diabetes, and metabolic syndrome. The IMPACT registry aims to assess the durability and hemodynamics of a novel bioprosthesis in a real-world setting with a focus on comorbidities.

Methods: IMPACT is a prospective, multicentre registry with an echocardiographic core lab that enrolled all-comer patients selected for SAVR with a new bioprosthesis in 21 sites in Europe.
Primary endpoints: All-cause mortality 1, 3, and 5 years after surgery. Secondary endpoints: All-cause mortality, cardiac and valve-related mortality. Severe hemodynamic structural valve deterioration (SVD). Overall and by pre-defined comorbidity.
We sought to determine all-cause, cardiac and valve-related mortality as well as hemodynamic performance and the incidence of severe structural valve deterioration (SVD) at 1 year.

Results: A total of 556 patients aged 63.4 ± 8.5 years, 29.0% female, and with a STS risk score of 1.7 ± 2.2% were enrolled. Most patients had hypertension (66.3%), followed by coronary artery disease (34.7%), diabetes mellitus (18.4%), and CKD stage ≥3 (15.8%). Overall, 44.1% had bicuspid valves and 58.3% underwent isolated AVR. Minimally invasive AVR was common (50.9%) with 16.4% of right anterior mini thoracotomy procedures. Median (IQR) procedure, cross-clamp, and cardiopulmonary bypass times were 191 (153;232), 70 (55;93), and 103 (81;133) minutes, respectively. Post-procedural mean pressure gradient was 11.2 ± 4.9 mmHg and the effective orifice area was 2.0 ± 0.6 cm 2 . The median length of stay in the intensive care unit was 24 (21; 49) hours with a hospitalization of 8 (7; 12) days. All-cause mortality rates were 1.4% at 30 days and 3.9% at 1
year, with valve-related mortality rates being 0.7% and 1.2%, respectively. Freedom rates from prosthetic endocarditis and thromboembolic events at 1 year were 98.1% (95% CI 96.9, 99.3) and 95.5% (93.6, 97.7), respectively. No cases of SVD stage 3 (VARC-3) and prosthetic valve thrombosis
were recorded. 3.0% of patients were in NYHA class III/IV compared to 41.2% at baseline.

Conclusion: One-year follow-up results confirm the satisfactory performance of the new bioprosthesis with stable haemodynamics and no valve thrombosis or SVD. IMPACT will follow up the present cohort for up to 5 years.

Identify the source of the funding for this research project: This work was supported with a research grant provided by Edwards Lifesciences (Nyon, Switzerland) to the sponsor Institute for Pharmacology and Preventive Medicine, Cloppenburg, Germany.