Objective: -In vitro evaluation of several prototype mechanical valves compared to present-day SAVR prosthetic valves. Method: -simulated normal cardiac pressures and flows -gravity pressure head column tester flows -recorded valve hydrodynamics and kinematics Results: -valves superior in performance to clinical controls Conclusions: -Prototype MHV candidates outperform the closing performance of present-day SAVR prosthetic valves, including bioprosthetic control.

Financial disclosure per coauthors HM and DG: University of British Columbia, Mitacs Accelerate, Vancouver, Canada, Karl Im, Angelo Medical LLC, LA, USA.

This study was funded by University of British Columbia, Mitacs Accelerate, Vancouver, Canada, Karl Im, Angeleno Medical LLC, Los Angeles, USA

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Yes

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Yes

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Yes

All data produced in the present study that is not presented in the manuscript are available upon reasonable request to the authors.