Abstract: The invention relates to a device and to a method for combining two images, especially for superimposition of static vascular maps (B), which were taken at different phases of the cardiac cycle and/or the respiratory cycle and were archived in a memory (6), on a current image (A) of a catheter (2, 8) in the vascular system (9). In the method, a defined section of a map image (B) around the estimated actual position of the catheter is selected and is displayed superimposed on the current image (A) in an image (C) on a monitor (10). The map image (B) used for this is preferably selected by means of an electrocardiogram to match the particular cardiac cycle. The position of the catheter relative to the map image (B) can be estimated using a distance image (D).

Abstract: Apparatus for navigating an instrument through an anatomical structure of a patient's body volume, comprising a table for supporting the patient and at least a first C-arm having a first X-ray source and a first X-ray detector for acquiring a first series of 2D-images of the instrument whilst manoeuvering through said anatomical structure, and further comprising a processing unit for the images which unit connects to a memory device, whereby the memory device holds pre-determined 3D-images of the patient's anatomical structure, and the processing unit is arranged for processing the 2D-images of the instrument and the 3D-images of the anatomical structure so as to provide merged 3D-images of the instrument that in use manoeuvers through said anatomical structure.