In the present invention, an imaging system and method is provided to obtain a fusion image of a patient anatomy used as a navigational 3D roadmap to guide an interventional device into the anatomy. The fusion image fuses in real-time, fluoroscopy images taken during the interventional procedure with pre-operative CTA images, so that the operator can see the anatomy in the fluoroscopy image without having to inject contrast agent. To correct for the deformation in the anatomy from the pre-op CTA images form the insertion of interventional devices during the procedure, a 3D ultrasound image is obtained after the insertion of the devices. The 3D ultrasound images are then utilized to correct the pre-op CTA images and provide the current vascular anatomy of the patient. This updated CTA image is fused with the intra-op fluoro images to provide an accurate 3D roadmap image that matches the deformed anatomy.
