Coronary artery centerline extraction using VMTK slicer extension

I am trying to extract centerline using extract centerline from VMTK module. But I’m able to extract only one part of branch ,not other part of branch of coronary vessels. How do I extract both branches centerlines. Can you suggest.

You must use a distinct endpoint list for the left coronaries. It’s even better to create 2 distinct surfaces, you can do that using the ‘Islands’ effect.