Merging together results from SimVascular and ITK-SNAP

I was hoping to get some help on the models I have created with SimVascular and ITK-SNAP. I wanted to combine the models (heart chambers) from ITK-SNAP and the models from SimVascular (coronary arteries, valves, aorta) on ParaView, and have used the “Transform Filter” already but have had no luck in getting the exact placement of the heart chambers with SimVascular. Does anyone have any background on this or the direction to follow? Thank you in advance and stay healthy.