Multiscale Multimodal Characterization and Simulation of Structural Alterations in Failed Bioprosthetic Heart Valves

Tsolaki, E.; Corso, P.; Zboray, R.; Avaro, J.; Appel, C.; Liebi, M.; Bertazzo, S.; Heinisch, P. P.; Carrel, T.; Obrist, D.; Herrmann, I. K.

doi:10.1101/2023.02.26.529530

bioRxiv · 10.1101/2023.02.26.529530

Multiscale Multimodal Characterization and Simulation of Structural Alterations in Failed Bioprosthetic Heart Valves

Tsolaki, E.·Corso, P.·Zboray, R.·Avaro, J.·Appel, C.·Liebi, M.·Bertazzo, S.·Heinisch, P. P.·Carrel, T.·Obrist, D.·Herrmann, I. K.

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Abstract

Calcific degeneration is the most frequent type of heart valve failure, with rising incidence due to the ageing population. The gold standard treatment to date is valve replacement. Unfortunately, calcification oftentimes re-occurs in bioprosthetic substitutes, with the governing processes remaining poorly understood. Here, we present a multiscale, multimodal analysis of disturbances and extensive mineralisation of the collagen network in failed bioprosthetic bovine pericardium valve explants with full histoanatomical context. In addition to highly abundant mineralized collagen fibres and fibrils, calcified micron-sized particles previously discovered in native valves were also prevalent on the aortic as well as the ventricular surface of bioprosthetic valves. The two mineral types (fibers and particles) were detectable even in early-stage mineralisation, prior to any macroscopic calcification. Based on multiscale multimodal characterisation and high-fidelity simulations, we demonstrate that mineral occurrence coincides with regions exposed to high haemodynamic and biomechanical indicators. These insights obtained by multiscale analysis of failed bioprosthetic valves may serve as groundwork for the evidence-based development of more durable alternatives. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=176 SRC="FIGDIR/small/529530v1_ufig1.gif" ALT="Figure 1"> View larger version (57K): org.highwire.dtl.DTLVardef@c7e0b5org.highwire.dtl.DTLVardef@71bdbdorg.highwire.dtl.DTLVardef@15fdc23org.highwire.dtl.DTLVardef@6dbd1c_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Tsolaki, E., Corso, P., Zboray, R., Avaro, J., Appel, C., Liebi, M., Bertazzo, S., Heinisch, P. P., Carrel, T., Obrist, D., Herrmann, I. K.. 2023-02-27. Multiscale Multimodal Characterization and Simulation of Structural Alterations in Failed Bioprosthetic Heart Valves. https://doi.org/10.1101/2023.02.26.529530

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