A device for medical imaging of coronary vessels includes a data extracting module configured to extract a first vessel map from computed tomography angiography data covering at least one reference cardiac phase and a set of second vessel maps from three-dimensional rotational angiography data covering at least one cardiac cycle. An interpolation module is configured to generate a series of warped versions of the first vessel map aligned with the set of second vessel maps, the series starting at the at least one reference cardiac phase. A merging module is configured to merge the series and the set of second vessel maps at the different phases in order to generate a final imaging map of the coronary vessels.