1. An angiographic image acquisition method for determining (S 3 ), based on a virtual 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 lesion with respect to overlap and perspective foreshortening, said method comprising the step of automatically adjusting (S 5 ) 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 said 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.