Coronary artery bifurcations are regions where the atherosclerotic plaque appears more frequently and where the percutaneous treatment is more challenging. To analyze these important vascular regions, in this paper is proposed a method for the extraction of realistic 3D models of coronary bifurcations combining information from pre operative computer tomography angiography (CTA) to obtain the 3D structure of the vessels and pre and post operative conventional coronary angiography (CCA) to extract a more accurate estimation of the lumen radius before and after stenting. The method proposed is semiautomatic, starting from a set of user defined landmarks, and has been successfully applied to data from five patients that underwent endovascular treatment in a coronary bifurcation. The results obtained are satisfactory by visual inspection and in comparison with manual measurements.