Systematic Investigation of Hydrodynamic Performance of Nine Valve in Valve Prostheses under Standardized Conditions: An In Vitro Study

Objectives: Transcatheter aortic valve in valve (ViV) implantation has become more and more popular for treatment of degenerated conventional aortic valve bioprosthesis (cAVBP). However, little is known about the hemodynamic impact of the ViV prosthesis (ViVP) for specific cAVBPs. The aim of this study was to analyze the hydrodynamic performance of the Evolut PRO prosthesis when implanted as ViV in eight cAVBP under standardized conditions in an in vitro setting.

Methods: An Evolut PRO 26-mm TAVI prosthesis was implanted in eight similar labeled size conventional AVBPs (Hancock(R) II, Avalus, Freestyle, Perimount, Perimount Magna Ease, INTUITY, Trifecta, TRIBIO) to measure the hydrodynamic performance in a pulse duplicator at 60 beats per minute and adjustable stroke volumes. Transvalvular pressure gradients and effective orifice area (EOA) were measured.

Result: Table 1 shows data with 70 mL stroke volume. Mean pressure gradient (MPG) differed significantly in all pairwise comparisons (p < 0.03) except for Evolut (TM) Pro in INTUITY (TM) versus Evolut (TM) Pro in Trifecta (TM). The EOA was statistically different in all pairwise comparisons except for Evolut (TM) Pro in Avalus (TM) versus Evolut (TM) Pro in Trifecta (TM). Amongst the investigated ViVPs, the Hancock (R) II presented with the lowest EOA and highest MPG, while the TRIBIO showed the highest EOA and lowest MPG.

Evolute Pro (26) in	Size	MPG (mm Hg)	PP (mm Hg)	Q (L/min)	EOA (cm2)
Trifecta	21	8.9 ± 0.2	17.3 ± 0.2	13.0 ± 0.1	1.5 ± 0.01
Freestyle	21	9.4 ± 0.1	25.4 ± 0.5	12.2 ± 0.1	1.4 ± 0.01
Magna Ease	21	8,3 ± 0,2	17.5 ± 0.3	13.4 ± 0.01	1.6 ± 0.01
Perimount	21	7.7 ± 0.2	15.0 ± 0.4	13.0 ± 0.1	1.6 ± 0.02
INTUITY	21	8.9 ± 0.1	16.7 ± 0.5	13.5 ± 0.1	1.6 ± 0.01
Hancock II	21	14.9 ± 0.3	25.2 ± 0.7	13.0 + 0.1	1.2 ± 0.01
Avalus	21	9.6 ± 0.3	20.6 ± 0.3	13.5 ± 0.2	1.5 ± 0.01
TRIBIO	19	6.4 ± 0.2	15.9 ± 0.3	12.3 ± 0.1	1.7 ± 0.02

Conclusion: The Evolut (TM) Pro as valve in valve showed significant differences in hydrodynamic performance depending on the conventional aortic valve bioprosthesis despite same label sizes. Such findings should be taken into account at the time of the initial surgical aortic valve replacement to achieve a good long-term result.

No conflict of interest has been declared by the author(s).

Publication History

Article published online:
19 February 2021