1. An angiographic image acquisition method for determining, based on a virtual three-dimensional (3D) representation of a region of interest in a patient's cardiovascular system to be graphically visualized, the optimal projection direction of a segmented target structure, or segmented target lesion, with respect to overlap and perspective foreshortening, said method comprising the step of automatically adjusting a collimator wedge position and/or aperture of a shutter mechanism used for collimating an X-ray beam emitted by an X-ray source to which said patient is exposed during an image-guided radiographic examination procedure based on data obtained as a result of the segmentation which indicate the contour and size of said target structure or lesion so as to reduce the region of interest to a field of view that covers said target structure or lesion together with a user-definable portion of the surrounding vasculature, said method being based on a method of virtual 3D representations for tracking a target structure or lesion over time, said method being applied to each of said virtual 3D representations and the segmentation is updated dynamically.