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International Journal of Bioprinting Evaluation of advanced visual computing solutions for the left atrial appendage occlusion

(FEOPS NV, Gent, Belgium), which offers simulations the geometries should be opened in half to facilitate free
of device deployment. The VIDAA platform provides movement of the device in the printed model. Despite its
a more comprehensive and interactive morphological limitations, most physicians thought 3D printing was the
characterization of the LAA, as well as interaction with 3D best technology to recognize the shape and do a mental
models of the LAA devices in a web-based environment quick strategy of the intervention for regular planning.
that does not require any software installation and easily In silico fluid simulations including LAAO devices
allows multicentric studies and collaborative decisions. were a unique source of valuable functional information,
Moreover, none of these solutions offer in silico fluid not available from current imaging modalities or other
simulations. The price of these commercial software tools computing solutions. Imaging cardiologists particularly
can also be an obstacle for including them in the clinical valued this option for evaluating regions with potential leaks
workflow of some hospitals. and complex flow after the LAAO implantation. However,
Participants in our study acknowledged the better the Ansys Discovery Live interface, which is difficult to
exploration of the 3D LAA anatomy with the VR system, interact with or move the CAD model of the device, was
due to an enhanced depth perception, 6 degrees of freedom not as user-friendly as the remaining technologies, as
interaction with 3D objects (both the LA geometry and the quantified in the SUS questionnaire. Participants would
device) and views from the interior of the cavity (not easy not include this technology in its current form, but they
to see even in 3D-printed models), all points important for would recommend incorporating it in other tools such as
the device implantation . For example, it was challenging VIDAA or VRIDAA. However, to integrate in silico fluid
[27]
for participants to truly grasp the depth and scaling of simulations in device-related decision-making, enough
human organs and device sizes (as well as their relation) credibility still needs to be built following verification,
only from 2D monitors, especially to detect possible validation, and uncertainty quantification standards such
leaks. Although the learning times for using the VRIDAA as the V&V40 guidelines , including sensitivity analysis
[41]
platform were short (i.e., a few minutes), the participants to identify the boundary conditions to provide more the
preferred the combination of web-based 3D imaging realistic fluid simulations . Moreover, the employed fluid
[39]
software in conjunction with 3D printing since it would be solver allowed user-interaction for estimating changes in
easier to fit in the current clinical workflow. The evaluated blood flow patterns with different device positions, but
VR setup that requires a certain allocated physical space is at the expense of simplifications (e.g., absence of wall
not adequate for use in most hospitals. However, affordable motion) that could be relevant to better mimicking of the
[42]
VR headsets with reasonable performance and resolution, interaction between the device and the anatomy .
including wireless solutions without requiring much room The comparison between the devices selected by the
space (e.g., the Oculus brand or even AR glasses), would be participants after each technology demonstrated the
a more appropriate alternative. relevance for interventional cardiologists to explore the

3D printing emerged as a useful technology for rapid data and anatomy fully in three dimensions with systems
prototyping, testing, and pre-operative planning. However, such as VR and including functional information from flow
the use of cheap materials in our study was a limiting simulations. In addition, there were consistent differences
factor since it did not realistically mimic the left atrial wall in device sizes selected with 2D-based tools compared
elastic properties, which are important to determine the to 3D alternatives. Beyond computational tools, there
interaction with the device once implanted. Specifically, it are other reasons related to the current LAAO clinical
made physicians pick sizes smaller than the one implanted workflow and training that could explain the large variation
or selected with the other technologies. The use of more on device sizing by different clinicians. For instance, the
realistic materials, such as the transparent and flexible existing manufacturer’s sizing recommendations overlap,
HeartFlex from Materialise NV (Leuven, Belgium) or resin, so a situation where a given LAA measurement could
was also noted by the participants, but would dramatically be covered by more than 1 device size might occur. The
increase the costs of the technology (approximately 200 consequence is that some clinicians would favor larger or
euros per piece vs. 1.5 euros with PLA). In addition, the smaller sizes in a subjective way (e.g., device manufacturer’s
use of real LAA occluders rather than 3D replicas could recommendation of 22 mm, some opting for 20 mm, and
improve the realism of the planning, but it will require others for 25 mm), increasing the importance of their
access to all LAAO designs and sizes, which is often not experience on the procedure for a successful LAAO
possible. Moreover, it was difficult to manipulate the implantation. Even with industry-supported training,
LAAO device inside the 3D-printed model since the only experienced clinicians selected a wide range of LAAO
open holes were the pulmonary veins and the mitral valve; device sizes. The integration of pre-operative planning

Volume 9 Issue 1 (2023) 270 https://doi.org/10.18063/ijb.v9i1.640