Question about segmentation of the aortic valve

Operating system: MacOS
Slicer version:4.11.20200930
Expected behavior:
Actual behavior:

Hey everyone!
Pretty new to Slicer, but I’m currently using it to segment a section of the aortic root so that the cusps of the aortic valve and the calcifications are clearly visible.

I used the “Grow from seeds” method to segment the aorta and the the calcified portions and then subsequently rendered the aorta hollow so that a “scissor” operation across it could reveal the valvular commisures.
I’m however having some difficulties with this as I’m unable to smoothen and render the valve correctly.
My current model looks fine for the most part with the exception of the aortic root area where the valve (my region of interest) is.
My goal is to create a model that looks somewhat like the result shown here:

I would really appreciate any help with regards to this.

Thank you so much!