In the surgical operation, the catheter can be used to collect the point clouds data and do the ablation operation. Then we can get the three-dimensional heart reconstruction model from point clouds using the surface reconstruction algorithm in visualization system. Usually, the heart model is displayed opaquely in the visualization window and light can not go through the object. So doctors could hardly see the location of the catheter inside the model in real-time system. In addition, sometimes doctors have to observe the internal structure and the interested region in the model for clinical diagnosis and analysis. Therefore, it is necessary for us to do the transparency to meet the doctor requirement. Transparency can be generally divided into overall transparency and local transparency. Sometimes it is difficult for doctor to recognize the relative position between the catheter and the model surface from the overall transparency. Allowing for this reason, in this paper, we not only introduce the overall transparency, but also propose two ways to deal with the interest region transparency. All the methods are implemented on VTK platform.